Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Get deep fsl,enable-lpsr sleep working #3

Open
alistair23 opened this issue Mar 16, 2021 · 5 comments
Open

Get deep fsl,enable-lpsr sleep working #3

alistair23 opened this issue Mar 16, 2021 · 5 comments
Labels

Comments

@alistair23
Copy link
Owner

There is a work in progress branch to add deep sleep support to the 5.4 kernel.

The problem is that deep sleep (called lpsr) doesn't work. The device will go into the deep sleep but I can't get it to wake up.

With lpsr disabled sleep/wake via the physical button work, but automatic sleep doesn't as automatic sleep appears to use lpsr. So I have disabled automatic sleep in Oxide and I have no issues.

This issue is tracking adding support for lpsr and hopefully that fixes the automatic sleep in Oxide and other apps.

@alistair23 alistair23 added the rM2 label Mar 16, 2021
@alistair23
Copy link
Owner Author

@boxfire

@boxfire
Copy link

boxfire commented Mar 17, 2021

Well I am sure there is just a missing step. Likely step 2 last bullet from the IMX Reference manual p. 44:

The i.MX 6 and i.MX 7 power management driver maps the low-power modes to the kernel power management states as listed below:

  • Standby-maps to STOP mode, which offers significant power saving, as all blocks in the system are put into a low-power state, except for Arm® core, which is still powered on, and memory is placed in self-refresh mode to retain its contents.
  • Mem (suspend to RAM) maps to DORMANT mode, which offers most significant power saving, as all blocks in the system are put into a low-power state, except for memory, which is placed in self-refresh mode to retain its contents. If there is"fsl,enable-lpsr" defined in DTB ocrams node, mem is mapped to LPSR mode instead of DORMANT, and all the blocks inthe system are put into power off state, except the LPSR, SNVS, and DRAM power domains.
  • System idle maps to WAIT mode.
  • If Arm Cortex®-M4 processor is alive together with Arm Cortex-A processor before the kernel enters standby/mem mode,and if Arm Cortex-M4 processor is not in its low-power idle mode, Arm Cortex-A processor triggers the SOC to enter WAIT mode instead of STOP mode to make sure that Arm Cortex-M4 processor can continue running.

The i.MX 6 and i.MX 7 power management driver performs the following steps to enter and exit low power mode:

  1. Allow the Cortex-A platform to issue a deep sleep mode request.
  2. If STOP or DORMANT mode:
    • Program i.MX 6 CCM_CLPCR or i.MX 7 GPC_LPCR_A7_BSC and GPC_SLPCR registers to set low-power control register.
    • If DORMANT mode, request switching off CPU power when pdn_req is asserted.
    • Request switching off embedded memory peripheral power when pdn_req is asserted.
    • Program GPC mask register to unmask wakeup interrupts.
  3. Call cpu_do_idle to execute WFI pending instructions for wait mode.
  4. Execute imx6_suspend or imx7_suspend in IRAM.
  5. In DORMANT mode, save Arm context, and change the drive strength of DDR PADs as "low" to minimize the power leakage in DDR PADs. Execute WFI pending instructions for stop mode.
  6. Generate a wakeup interrupt and exit low-power mode. In DORMANT mode, restore Arm core and DDR drive strength.

In DORMANT mode, the i.MX 6 and i.MX 7 can assert the PMIC_STBY_REQ pin to the PMIC and request a voltage change.The U-Boot or Machine-Specific Layer (MSL) usually sets the standby voltage in STOP mode according to i.MX 6 and i.MX 7data sheet.

@boxfire
Copy link

boxfire commented Mar 17, 2021

Associated code for imx7d is in

 * arch/arm/mach-imx/pm-imx7.c
 * arch/arm/mach-imx/suspend-imx7.S
 * arch/arm/mach-imx/cpuidle-imx7d.c
 * arch/arm/mach-imx/imx7d_low_power_idle.

If CONFIG_PM, CONFIG_SUSPEND are on then low power mode should be available from that source code.

So with all of that I might suggest turning on all the debug stuff in the 4.14.78 kernel, perhaps with kernel function tracing, checking out what gets called / taken, and then making sure all of that can happen in the 5.4 kernel. I mean there is probably something obvious like the wakeup interrupt not being programmed correctly, but I can't say easily

@boxfire
Copy link

boxfire commented Mar 17, 2021

interesting. As a debug stopgap:

echo enabled > /sys/class/tty/ttymxc0/power/wakeup

(replace with appropriate pogo uart once I figure out whats going on there?)

@boxfire
Copy link

boxfire commented Mar 17, 2021

I wonder if its as simple as hitting that for the power button gpio?

alistair23 pushed a commit that referenced this issue Mar 21, 2021
Add 3 new tests for tag-based KASAN modes:

1. Check that match-all pointer tag is not assigned randomly.
2. Check that 0xff works as a match-all pointer tag.
3. Check that there are no match-all memory tags.

Note, that test #3 causes a significant number (255) of KASAN reports
to be printed during execution for the SW_TAGS mode.

[[email protected]: export kasan_poison]
  Link: https://lkml.kernel.org/r/[email protected]
[[email protected]: s/EXPORT_SYMBOL_GPL/EXPORT_SYMBOL/, per Andrey]

Link: https://linux-review.googlesource.com/id/I78f1375efafa162b37f3abcb2c5bc2f3955dfd8e
Link: https://lkml.kernel.org/r/da841a5408e2204bf25f3b23f70540a65844e8a4.1610733117.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Reviewed-by: Marco Elver <[email protected]>
Reviewed-by: Alexander Potapenko <[email protected]>
Cc: Andrey Ryabinin <[email protected]>
Cc: Branislav Rankov <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Dmitry Vyukov <[email protected]>
Cc: Evgenii Stepanov <[email protected]>
Cc: Kevin Brodsky <[email protected]>
Cc: Peter Collingbourne <[email protected]>
Cc: Vincenzo Frascino <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 21, 2021
Calling btrfs_qgroup_reserve_meta_prealloc from
btrfs_delayed_inode_reserve_metadata can result in flushing delalloc
while holding a transaction and delayed node locks. This is deadlock
prone. In the past multiple commits:

 * ae5e070 ("btrfs: qgroup: don't try to wait flushing if we're
already holding a transaction")

 * 6f23277 ("btrfs: qgroup: don't commit transaction when we already
 hold the handle")

Tried to solve various aspects of this but this was always a
whack-a-mole game. Unfortunately those 2 fixes don't solve a deadlock
scenario involving btrfs_delayed_node::mutex. Namely, one thread
can call btrfs_dirty_inode as a result of reading a file and modifying
its atime:

  PID: 6963   TASK: ffff8c7f3f94c000  CPU: 2   COMMAND: "test"
  #0  __schedule at ffffffffa529e07d
  #1  schedule at ffffffffa529e4ff
  #2  schedule_timeout at ffffffffa52a1bdd
  #3  wait_for_completion at ffffffffa529eeea             <-- sleeps with delayed node mutex held
  #4  start_delalloc_inodes at ffffffffc0380db5
  #5  btrfs_start_delalloc_snapshot at ffffffffc0393836
  #6  try_flush_qgroup at ffffffffc03f04b2
  torvalds#7  __btrfs_qgroup_reserve_meta at ffffffffc03f5bb6     <-- tries to reserve space and starts delalloc inodes.
  torvalds#8  btrfs_delayed_update_inode at ffffffffc03e31aa      <-- acquires delayed node mutex
  torvalds#9  btrfs_update_inode at ffffffffc0385ba8
 torvalds#10  btrfs_dirty_inode at ffffffffc038627b               <-- TRANSACTIION OPENED
 torvalds#11  touch_atime at ffffffffa4cf0000
 torvalds#12  generic_file_read_iter at ffffffffa4c1f123
 torvalds#13  new_sync_read at ffffffffa4ccdc8a
 torvalds#14  vfs_read at ffffffffa4cd0849
 torvalds#15  ksys_read at ffffffffa4cd0bd1
 torvalds#16  do_syscall_64 at ffffffffa4a052eb
 torvalds#17  entry_SYSCALL_64_after_hwframe at ffffffffa540008c

This will cause an asynchronous work to flush the delalloc inodes to
happen which can try to acquire the same delayed_node mutex:

  PID: 455    TASK: ffff8c8085fa4000  CPU: 5   COMMAND: "kworker/u16:30"
  #0  __schedule at ffffffffa529e07d
  #1  schedule at ffffffffa529e4ff
  #2  schedule_preempt_disabled at ffffffffa529e80a
  #3  __mutex_lock at ffffffffa529fdcb                    <-- goes to sleep, never wakes up.
  #4  btrfs_delayed_update_inode at ffffffffc03e3143      <-- tries to acquire the mutex
  #5  btrfs_update_inode at ffffffffc0385ba8              <-- this is the same inode that pid 6963 is holding
  #6  cow_file_range_inline.constprop.78 at ffffffffc0386be7
  torvalds#7  cow_file_range at ffffffffc03879c1
  torvalds#8  btrfs_run_delalloc_range at ffffffffc038894c
  torvalds#9  writepage_delalloc at ffffffffc03a3c8f
 torvalds#10  __extent_writepage at ffffffffc03a4c01
 torvalds#11  extent_write_cache_pages at ffffffffc03a500b
 torvalds#12  extent_writepages at ffffffffc03a6de2
 torvalds#13  do_writepages at ffffffffa4c277eb
 torvalds#14  __filemap_fdatawrite_range at ffffffffa4c1e5bb
 torvalds#15  btrfs_run_delalloc_work at ffffffffc0380987         <-- starts running delayed nodes
 torvalds#16  normal_work_helper at ffffffffc03b706c
 torvalds#17  process_one_work at ffffffffa4aba4e4
 torvalds#18  worker_thread at ffffffffa4aba6fd
 torvalds#19  kthread at ffffffffa4ac0a3d
 torvalds#20  ret_from_fork at ffffffffa54001ff

To fully address those cases the complete fix is to never issue any
flushing while holding the transaction or the delayed node lock. This
patch achieves it by calling qgroup_reserve_meta directly which will
either succeed without flushing or will fail and return -EDQUOT. In the
latter case that return value is going to be propagated to
btrfs_dirty_inode which will fallback to start a new transaction. That's
fine as the majority of time we expect the inode will have
BTRFS_DELAYED_NODE_INODE_DIRTY flag set which will result in directly
copying the in-memory state.

Fixes: c53e965 ("btrfs: qgroup: try to flush qgroup space when we get -EDQUOT")
CC: [email protected] # 5.10+
Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Nikolay Borisov <[email protected]>
Signed-off-by: David Sterba <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 21, 2021
The evlist has the maps with its own refcounts so we don't need to set
the pointers to NULL.  Otherwise following error was reported by Asan.

  # perf test -v 4
   4: Read samples using the mmap interface      :
  --- start ---
  test child forked, pid 139782
  mmap size 528384B

  =================================================================
  ==139782==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
    #0 0x7f1f76daee8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
    #1 0x564ba21a0fea in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79
    #2 0x564ba21a1a0f in perf_cpu_map__read /home/namhyung/project/linux/tools/lib/perf/cpumap.c:149
    #3 0x564ba21a21cf in cpu_map__read_all_cpu_map /home/namhyung/project/linux/tools/lib/perf/cpumap.c:166
    #4 0x564ba21a21cf in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:181
    #5 0x564ba1e48298 in test__basic_mmap tests/mmap-basic.c:55
    #6 0x564ba1e278fb in run_test tests/builtin-test.c:428
    torvalds#7 0x564ba1e278fb in test_and_print tests/builtin-test.c:458
    torvalds#8 0x564ba1e29a53 in __cmd_test tests/builtin-test.c:679
    torvalds#9 0x564ba1e29a53 in cmd_test tests/builtin-test.c:825
    torvalds#10 0x564ba1e95cb4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    torvalds#11 0x564ba1d1fa88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    torvalds#12 0x564ba1d1fa88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    torvalds#13 0x564ba1d1fa88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    torvalds#14 0x7f1f768e4d09 in __libc_start_main ../csu/libc-start.c:308

    ...
  test child finished with 1
  ---- end ----
  Read samples using the mmap interface: FAILED!
  failed to open shell test directory: /home/namhyung/libexec/perf-core/tests/shell

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 21, 2021
The evlist has the maps with its own refcounts so we don't need to set
the pointers to NULL.  Otherwise following error was reported by Asan.

Also change the goto label since it doesn't need to have two.

  # perf test -v 24
  24: Number of exit events of a simple workload :
  --- start ---
  test child forked, pid 145915
  mmap size 528384B

  =================================================================
  ==145915==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 32 byte(s) in 1 object(s) allocated from:
    #0 0x7fc44e50d1f8 in __interceptor_realloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:164
    #1 0x561cf50f4d2e in perf_thread_map__realloc /home/namhyung/project/linux/tools/lib/perf/threadmap.c:23
    #2 0x561cf4eeb949 in thread_map__new_by_tid util/thread_map.c:63
    #3 0x561cf4db7fd2 in test__task_exit tests/task-exit.c:74
    #4 0x561cf4d798fb in run_test tests/builtin-test.c:428
    #5 0x561cf4d798fb in test_and_print tests/builtin-test.c:458
    #6 0x561cf4d7ba53 in __cmd_test tests/builtin-test.c:679
    torvalds#7 0x561cf4d7ba53 in cmd_test tests/builtin-test.c:825
    torvalds#8 0x561cf4de7d04 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    torvalds#9 0x561cf4c71a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    torvalds#10 0x561cf4c71a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    torvalds#11 0x561cf4c71a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    torvalds#12 0x7fc44e042d09 in __libc_start_main ../csu/libc-start.c:308

    ...
  test child finished with 1
  ---- end ----
  Number of exit events of a simple workload: FAILED!

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 21, 2021
The evlist has the maps with its own refcounts so we don't need to set
the pointers to NULL.  Otherwise following error was reported by Asan.

Also change the goto label since it doesn't need to have two.

  # perf test -v 25
  25: Software clock events period values        :
  --- start ---
  test child forked, pid 149154
  mmap size 528384B
  mmap size 528384B

  =================================================================
  ==149154==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 32 byte(s) in 1 object(s) allocated from:
    #0 0x7fef5cd071f8 in __interceptor_realloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:164
    #1 0x56260d5e8b8e in perf_thread_map__realloc /home/namhyung/project/linux/tools/lib/perf/threadmap.c:23
    #2 0x56260d3df7a9 in thread_map__new_by_tid util/thread_map.c:63
    #3 0x56260d2ac6b2 in __test__sw_clock_freq tests/sw-clock.c:65
    #4 0x56260d26d8fb in run_test tests/builtin-test.c:428
    #5 0x56260d26d8fb in test_and_print tests/builtin-test.c:458
    #6 0x56260d26fa53 in __cmd_test tests/builtin-test.c:679
    torvalds#7 0x56260d26fa53 in cmd_test tests/builtin-test.c:825
    torvalds#8 0x56260d2dbb64 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    torvalds#9 0x56260d165a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    torvalds#10 0x56260d165a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    torvalds#11 0x56260d165a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    torvalds#12 0x7fef5c83cd09 in __libc_start_main ../csu/libc-start.c:308

    ...
  test child finished with 1
  ---- end ----
  Software clock events period values      : FAILED!

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 21, 2021
The evlist and the cpu/thread maps should be released together.
Otherwise following error was reported by Asan.

Note that this test still has memory leaks in DSOs so it still fails
even after this change.  I'll take a look at that too.

  # perf test -v 26
  26: Object code reading                        :
  --- start ---
  test child forked, pid 154184
  Looking at the vmlinux_path (8 entries long)
  symsrc__init: build id mismatch for vmlinux.
  symsrc__init: cannot get elf header.
  Using /proc/kcore for kernel data
  Using /proc/kallsyms for symbols
  Parsing event 'cycles'
  mmap size 528384B
  ...
  =================================================================
  ==154184==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 439 byte(s) in 1 object(s) allocated from:
    #0 0x7fcb66e77037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
    #1 0x55ad9b7e821e in dso__new_id util/dso.c:1256
    #2 0x55ad9b8cfd4a in __machine__addnew_vdso util/vdso.c:132
    #3 0x55ad9b8cfd4a in machine__findnew_vdso util/vdso.c:347
    #4 0x55ad9b845b7e in map__new util/map.c:176
    #5 0x55ad9b8415a2 in machine__process_mmap2_event util/machine.c:1787
    #6 0x55ad9b8fab16 in perf_tool__process_synth_event util/synthetic-events.c:64
    torvalds#7 0x55ad9b8fab16 in perf_event__synthesize_mmap_events util/synthetic-events.c:499
    torvalds#8 0x55ad9b8fbfdf in __event__synthesize_thread util/synthetic-events.c:741
    torvalds#9 0x55ad9b8ff3e3 in perf_event__synthesize_thread_map util/synthetic-events.c:833
    torvalds#10 0x55ad9b738585 in do_test_code_reading tests/code-reading.c:608
    torvalds#11 0x55ad9b73b25d in test__code_reading tests/code-reading.c:722
    torvalds#12 0x55ad9b6f28fb in run_test tests/builtin-test.c:428
    torvalds#13 0x55ad9b6f28fb in test_and_print tests/builtin-test.c:458
    torvalds#14 0x55ad9b6f4a53 in __cmd_test tests/builtin-test.c:679
    torvalds#15 0x55ad9b6f4a53 in cmd_test tests/builtin-test.c:825
    torvalds#16 0x55ad9b760cc4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    torvalds#17 0x55ad9b5eaa88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    torvalds#18 0x55ad9b5eaa88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    torvalds#19 0x55ad9b5eaa88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    torvalds#20 0x7fcb669acd09 in __libc_start_main ../csu/libc-start.c:308

    ...
  SUMMARY: AddressSanitizer: 471 byte(s) leaked in 2 allocation(s).
  test child finished with 1
  ---- end ----
  Object code reading: FAILED!

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 21, 2021
The evlist and the cpu/thread maps should be released together.
Otherwise following error was reported by Asan.

  $ perf test -v 28
  28: Use a dummy software event to keep tracking:
  --- start ---
  test child forked, pid 156810
  mmap size 528384B

  =================================================================
  ==156810==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
    #0 0x7f637d2bce8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
    #1 0x55cc6295cffa in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79
    #2 0x55cc6295da1f in perf_cpu_map__read /home/namhyung/project/linux/tools/lib/perf/cpumap.c:149
    #3 0x55cc6295e1df in cpu_map__read_all_cpu_map /home/namhyung/project/linux/tools/lib/perf/cpumap.c:166
    #4 0x55cc6295e1df in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:181
    #5 0x55cc626287cf in test__keep_tracking tests/keep-tracking.c:84
    #6 0x55cc625e38fb in run_test tests/builtin-test.c:428
    torvalds#7 0x55cc625e38fb in test_and_print tests/builtin-test.c:458
    torvalds#8 0x55cc625e5a53 in __cmd_test tests/builtin-test.c:679
    torvalds#9 0x55cc625e5a53 in cmd_test tests/builtin-test.c:825
    torvalds#10 0x55cc62651cc4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    torvalds#11 0x55cc624dba88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    torvalds#12 0x55cc624dba88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    torvalds#13 0x55cc624dba88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    torvalds#14 0x7f637cdf2d09 in __libc_start_main ../csu/libc-start.c:308

  SUMMARY: AddressSanitizer: 72 byte(s) leaked in 2 allocation(s).
  test child finished with 1
  ---- end ----
  Use a dummy software event to keep tracking: FAILED!

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 21, 2021
The evlist and cpu/thread maps should be released together.
Otherwise the following error was reported by Asan.

  $ perf test -v 35
  35: Track with sched_switch                    :
  --- start ---
  test child forked, pid 159287
  Using CPUID GenuineIntel-6-8E-C
  mmap size 528384B
  1295 events recorded

  =================================================================
  ==159287==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
    #0 0x7fa28d9a2e8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
    #1 0x5652f5a5affa in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79
    #2 0x5652f5a5ba1f in perf_cpu_map__read /home/namhyung/project/linux/tools/lib/perf/cpumap.c:149
    #3 0x5652f5a5c1df in cpu_map__read_all_cpu_map /home/namhyung/project/linux/tools/lib/perf/cpumap.c:166
    #4 0x5652f5a5c1df in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:181
    #5 0x5652f5723bbf in test__switch_tracking tests/switch-tracking.c:350
    #6 0x5652f56e18fb in run_test tests/builtin-test.c:428
    torvalds#7 0x5652f56e18fb in test_and_print tests/builtin-test.c:458
    torvalds#8 0x5652f56e3a53 in __cmd_test tests/builtin-test.c:679
    torvalds#9 0x5652f56e3a53 in cmd_test tests/builtin-test.c:825
    torvalds#10 0x5652f574fcc4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    torvalds#11 0x5652f55d9a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    torvalds#12 0x5652f55d9a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    torvalds#13 0x5652f55d9a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    torvalds#14 0x7fa28d4d8d09 in __libc_start_main ../csu/libc-start.c:308

  SUMMARY: AddressSanitizer: 72 byte(s) leaked in 2 allocation(s).
  test child finished with 1
  ---- end ----
  Track with sched_switch: FAILED!

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 21, 2021
It missed to call perf_thread_map__put() after using the map.

  $ perf test -v 43
  43: Synthesize thread map                      :
  --- start ---
  test child forked, pid 162640

  =================================================================
  ==162640==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 32 byte(s) in 1 object(s) allocated from:
    #0 0x7fd48cdaa1f8 in __interceptor_realloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:164
    #1 0x563e6d5f8d0e in perf_thread_map__realloc /home/namhyung/project/linux/tools/lib/perf/threadmap.c:23
    #2 0x563e6d3ef69a in thread_map__new_by_pid util/thread_map.c:46
    #3 0x563e6d2cec90 in test__thread_map_synthesize tests/thread-map.c:97
    #4 0x563e6d27d8fb in run_test tests/builtin-test.c:428
    #5 0x563e6d27d8fb in test_and_print tests/builtin-test.c:458
    #6 0x563e6d27fa53 in __cmd_test tests/builtin-test.c:679
    torvalds#7 0x563e6d27fa53 in cmd_test tests/builtin-test.c:825
    torvalds#8 0x563e6d2ebce4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    torvalds#9 0x563e6d175a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    torvalds#10 0x563e6d175a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    torvalds#11 0x563e6d175a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    torvalds#12 0x7fd48c8dfd09 in __libc_start_main ../csu/libc-start.c:308

  SUMMARY: AddressSanitizer: 8224 byte(s) leaked in 2 allocation(s).
  test child finished with 1
  ---- end ----
  Synthesize thread map: FAILED!

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 21, 2021
It should be released after printing the map.

  $ perf test -v 52
  52: Print cpu map                              :
  --- start ---
  test child forked, pid 172233

  =================================================================
  ==172233==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 156 byte(s) in 1 object(s) allocated from:
    #0 0x7fc472518e8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
    #1 0x55e63b378f7a in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79
    #2 0x55e63b37a05c in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:237
    #3 0x55e63b056d16 in cpu_map_print tests/cpumap.c:102
    #4 0x55e63b056d16 in test__cpu_map_print tests/cpumap.c:120
    #5 0x55e63afff8fb in run_test tests/builtin-test.c:428
    #6 0x55e63afff8fb in test_and_print tests/builtin-test.c:458
    torvalds#7 0x55e63b001a53 in __cmd_test tests/builtin-test.c:679
    torvalds#8 0x55e63b001a53 in cmd_test tests/builtin-test.c:825
    torvalds#9 0x55e63b06dc44 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    torvalds#10 0x55e63aef7a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    torvalds#11 0x55e63aef7a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    torvalds#12 0x55e63aef7a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    torvalds#13 0x7fc47204ed09 in __libc_start_main ../csu/libc-start.c:308
  ...

  SUMMARY: AddressSanitizer: 448 byte(s) leaked in 7 allocation(s).
  test child finished with 1
  ---- end ----
  Print cpu map: FAILED!

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 21, 2021
It should release the maps at the end.

  $ perf test -v 71
  71: Convert perf time to TSC                   :
  --- start ---
  test child forked, pid 178744
  mmap size 528384B
  1st event perf time 59207256505278 tsc 13187166645142
  rdtsc          time 59207256542151 tsc 13187166723020
  2nd event perf time 59207256543749 tsc 13187166726393

  =================================================================
  ==178744==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
    #0 0x7faf601f9e8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
    #1 0x55b620cfc00a in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79
    #2 0x55b620cfca2f in perf_cpu_map__read /home/namhyung/project/linux/tools/lib/perf/cpumap.c:149
    #3 0x55b620cfd1ef in cpu_map__read_all_cpu_map /home/namhyung/project/linux/tools/lib/perf/cpumap.c:166
    #4 0x55b620cfd1ef in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:181
    #5 0x55b6209ef1b2 in test__perf_time_to_tsc tests/perf-time-to-tsc.c:73
    #6 0x55b6209828fb in run_test tests/builtin-test.c:428
    torvalds#7 0x55b6209828fb in test_and_print tests/builtin-test.c:458
    torvalds#8 0x55b620984a53 in __cmd_test tests/builtin-test.c:679
    torvalds#9 0x55b620984a53 in cmd_test tests/builtin-test.c:825
    torvalds#10 0x55b6209f0cd4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    torvalds#11 0x55b62087aa88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    torvalds#12 0x55b62087aa88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    torvalds#13 0x55b62087aa88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    torvalds#14 0x7faf5fd2fd09 in __libc_start_main ../csu/libc-start.c:308

  SUMMARY: AddressSanitizer: 72 byte(s) leaked in 2 allocation(s).
  test child finished with 1
  ---- end ----
  Convert perf time to TSC: FAILED!

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 21, 2021
I got a segfault when using -r option with event groups.  The option
makes it run the workload multiple times and it will reuse the evlist
and evsel for each run.

While most of resources are allocated and freed properly, the id hash
in the evlist was not and it resulted in the bug.  You can see it with
the address sanitizer like below:

  $ perf stat -r 100 -e '{cycles,instructions}' true
  =================================================================
  ==693052==ERROR: AddressSanitizer: heap-use-after-free on
      address 0x6080000003d0 at pc 0x558c57732835 bp 0x7fff1526adb0 sp 0x7fff1526ada8
  WRITE of size 8 at 0x6080000003d0 thread T0
    #0 0x558c57732834 in hlist_add_head /home/namhyung/project/linux/tools/include/linux/list.h:644
    #1 0x558c57732834 in perf_evlist__id_hash /home/namhyung/project/linux/tools/lib/perf/evlist.c:237
    #2 0x558c57732834 in perf_evlist__id_add /home/namhyung/project/linux/tools/lib/perf/evlist.c:244
    #3 0x558c57732834 in perf_evlist__id_add_fd /home/namhyung/project/linux/tools/lib/perf/evlist.c:285
    #4 0x558c5747733e in store_evsel_ids util/evsel.c:2765
    #5 0x558c5747733e in evsel__store_ids util/evsel.c:2782
    #6 0x558c5730b717 in __run_perf_stat /home/namhyung/project/linux/tools/perf/builtin-stat.c:895
    torvalds#7 0x558c5730b717 in run_perf_stat /home/namhyung/project/linux/tools/perf/builtin-stat.c:1014
    torvalds#8 0x558c5730b717 in cmd_stat /home/namhyung/project/linux/tools/perf/builtin-stat.c:2446
    torvalds#9 0x558c57427c24 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    torvalds#10 0x558c572b1a48 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    torvalds#11 0x558c572b1a48 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    torvalds#12 0x558c572b1a48 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    torvalds#13 0x7fcadb9f7d09 in __libc_start_main ../csu/libc-start.c:308
    torvalds#14 0x558c572b60f9 in _start (/home/namhyung/project/linux/tools/perf/perf+0x45d0f9)

Actually the nodes in the hash table are struct perf_stream_id and
they were freed in the previous run.  Fix it by resetting the hash.

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 30, 2021
Ido Schimmel says:

====================
mlxsw: Various fixes

This patchset contains various fixes for mlxsw.

Patch #1 fixes a race condition in a selftest. The race and fix are
explained in detail in the changelog.

Patch #2 re-adds a link mode that was wrongly removed, resulting in a
regression in some setups.

Patch #3 fixes a race condition in route installation with nexthop
objects.

Please consider patches #2 and #3 for stable.
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 30, 2021
When running the latest kernel on an sc7180 with KASAN I got this
splat:
  BUG: KASAN: slab-out-of-bounds in a6xx_gpu_init+0x618/0x644
  Read of size 4 at addr ffffff8088f36100 by task kworker/7:1/58
  CPU: 7 PID: 58 Comm: kworker/7:1 Not tainted 5.11.0+ #3
  Hardware name: Google Lazor (rev1 - 2) with LTE (DT)
  Workqueue: events deferred_probe_work_func
  Call trace:
   dump_backtrace+0x0/0x3a8
   show_stack+0x24/0x30
   dump_stack+0x174/0x1e0
   print_address_description+0x70/0x2e4
   kasan_report+0x178/0x1bc
   __asan_report_load4_noabort+0x44/0x50
   a6xx_gpu_init+0x618/0x644
   adreno_bind+0x26c/0x438

This is because the speed bin is defined like this:
  gpu_speed_bin: gpu_speed_bin@1d2 {
    reg = <0x1d2 0x2>;
    bits = <5 8>;
  };

As you can see the "length" is 2 bytes. That means that the nvmem
subsystem allocates only 2 bytes. The GPU code, however, was casting
the pointer allocated by nvmem to a (u32 *) and dereferencing. That's
not so good.

Let's fix this to just use the nvmem_cell_read_u16() accessor function
which simplifies things and also gets rid of the splat.

Let's also put an explicit conversion from little endian in place just
to make things clear. The nvmem subsystem today is assuming little
endian and this makes it clear. Specifically, the way the above sc7180
cell is interpreted:

NVMEM:
 +--------+--------+--------+--------+--------+
 | ...... | 0x1d3  | 0x1d2  | ...... | 0x000  |
 +--------+--------+--------+--------+--------+
              ^       ^
             msb     lsb

You can see that the least significant data is at the lower address
which is little endian.

NOTE: someone who is truly paying attention might wonder about me
picking the "u16" version of this accessor instead of the "u8" (since
the value is 8 bits big) or the u32 version (just for fun). At the
moment you need to pick the accessor that exactly matches the length
the cell was specified as in the device tree. Hopefully future
patches to the nvmem subsystem will fix this.

Fixes: fe7952c ("drm/msm: Add speed-bin support to a618 gpu")
Signed-off-by: Douglas Anderson <[email protected]>
Signed-off-by: Rob Clark <[email protected]>
alistair23 pushed a commit that referenced this issue Mar 30, 2021
I got several memory leak reports from Asan with a simple command.  It
was because VDSO is not released due to the refcount.  Like in
__dsos_addnew_id(), it should put the refcount after adding to the list.

  $ perf record true
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.030 MB perf.data (10 samples) ]

  =================================================================
  ==692599==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 439 byte(s) in 1 object(s) allocated from:
    #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
    #1 0x559bce4aa8ee in dso__new_id util/dso.c:1256
    #2 0x559bce59245a in __machine__addnew_vdso util/vdso.c:132
    #3 0x559bce59245a in machine__findnew_vdso util/vdso.c:347
    #4 0x559bce50826c in map__new util/map.c:175
    #5 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787
    #6 0x559bce512f6b in machines__deliver_event util/session.c:1481
    torvalds#7 0x559bce515107 in perf_session__deliver_event util/session.c:1551
    torvalds#8 0x559bce51d4d2 in do_flush util/ordered-events.c:244
    torvalds#9 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323
    torvalds#10 0x559bce519bea in __perf_session__process_events util/session.c:2268
    torvalds#11 0x559bce519bea in perf_session__process_events util/session.c:2297
    torvalds#12 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017
    torvalds#13 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234
    torvalds#14 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026
    torvalds#15 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858
    torvalds#16 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    torvalds#17 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    torvalds#18 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    torvalds#19 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    torvalds#20 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308

  Indirect leak of 32 byte(s) in 1 object(s) allocated from:
    #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
    #1 0x559bce520907 in nsinfo__copy util/namespaces.c:169
    #2 0x559bce50821b in map__new util/map.c:168
    #3 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787
    #4 0x559bce512f6b in machines__deliver_event util/session.c:1481
    #5 0x559bce515107 in perf_session__deliver_event util/session.c:1551
    #6 0x559bce51d4d2 in do_flush util/ordered-events.c:244
    torvalds#7 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323
    torvalds#8 0x559bce519bea in __perf_session__process_events util/session.c:2268
    torvalds#9 0x559bce519bea in perf_session__process_events util/session.c:2297
    torvalds#10 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017
    torvalds#11 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234
    torvalds#12 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026
    torvalds#13 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858
    torvalds#14 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    torvalds#15 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    torvalds#16 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    torvalds#17 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    torvalds#18 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308

  SUMMARY: AddressSanitizer: 471 byte(s) leaked in 2 allocation(s).

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
alistair23 pushed a commit that referenced this issue Oct 25, 2021
Pablo Neira Ayuso says:

====================
Netfilter fixes for net (v2)

The following patchset contains Netfilter fixes for net:

1) Move back the defrag users fields to the global netns_nf area.
   Kernel fails to boot if conntrack is builtin and kernel is booted
   with: nf_conntrack.enable_hooks=1. From Florian Westphal.

2) Rule event notification is missing relevant context such as
   the position handle and the NLM_F_APPEND flag.

3) Rule replacement is expanded to add + delete using the existing
   rule handle, reverse order of this operation so it makes sense
   from rule notification standpoint.

4) Propagate to userspace the NLM_F_CREATE and NLM_F_EXCL flags
   from the rule notification path.

Patches #2, #3 and #4 are used by 'nft monitor' and 'iptables-monitor'
userspace utilities which are not correctly representing the following
operations through netlink notifications:

- rule insertions
- rule addition/insertion from position handle
- create table/chain/set/map/flowtable/...
====================

Signed-off-by: David S. Miller <[email protected]>
alistair23 pushed a commit that referenced this issue Oct 25, 2021
When passing 'phys' in the devicetree to describe the USB PHY phandle
(which is the recommended way according to
Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt) the
following NULL pointer dereference is observed on i.MX7 and i.MX8MM:

[    1.489344] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000098
[    1.498170] Mem abort info:
[    1.500966]   ESR = 0x96000044
[    1.504030]   EC = 0x25: DABT (current EL), IL = 32 bits
[    1.509356]   SET = 0, FnV = 0
[    1.512416]   EA = 0, S1PTW = 0
[    1.515569]   FSC = 0x04: level 0 translation fault
[    1.520458] Data abort info:
[    1.523349]   ISV = 0, ISS = 0x00000044
[    1.527196]   CM = 0, WnR = 1
[    1.530176] [0000000000000098] user address but active_mm is swapper
[    1.536544] Internal error: Oops: 96000044 [#1] PREEMPT SMP
[    1.542125] Modules linked in:
[    1.545190] CPU: 3 PID: 7 Comm: kworker/u8:0 Not tainted 5.14.0-dirty #3
[    1.551901] Hardware name: Kontron i.MX8MM N801X S (DT)
[    1.557133] Workqueue: events_unbound deferred_probe_work_func
[    1.562984] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO BTYPE=--)
[    1.568998] pc : imx7d_charger_detection+0x3f0/0x510
[    1.573973] lr : imx7d_charger_detection+0x22c/0x510

This happens because the charger functions check for the phy presence
inside the imx_usbmisc_data structure (data->usb_phy), but the chipidea
core populates the usb_phy passed via 'phys' inside 'struct ci_hdrc'
(ci->usb_phy) instead.

This causes the NULL pointer dereference inside imx7d_charger_detection().

Fix it by also searching for 'phys' in case 'fsl,usbphy' is not found.

Tested on a imx7s-warp board.

Fixes: 746f316 ("usb: chipidea: introduce imx7d USB charger detection")
Cc: [email protected]
Reported-by: Heiko Thiery <[email protected]>
Tested-by: Frieder Schrempf <[email protected]>
Reviewed-by: Frieder Schrempf <[email protected]>
Acked-by: Peter Chen <[email protected]>
Signed-off-by: Fabio Estevam <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
alistair23 pushed a commit that referenced this issue Oct 25, 2021
…rbage value

Currently, when the rule related to IDLETIMER is added, idletimer_tg timer
structure is initialized by kmalloc on executing idletimer_tg_create
function. However, in this process timer->timer_type is not defined to
a specific value. Thus, timer->timer_type has garbage value and it occurs
kernel panic. So, this commit fixes the panic by initializing
timer->timer_type using kzalloc instead of kmalloc.

Test commands:
    # iptables -A OUTPUT -j IDLETIMER --timeout 1 --label test
    $ cat /sys/class/xt_idletimer/timers/test
      Killed

Splat looks like:
    BUG: KASAN: user-memory-access in alarm_expires_remaining+0x49/0x70
    Read of size 8 at addr 0000002e8c7bc4c8 by task cat/917
    CPU: 12 PID: 917 Comm: cat Not tainted 5.14.0+ #3 79940a339f71eb14fc81aee1757a20d5bf13eb0e
    Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014
    Call Trace:
     dump_stack_lvl+0x6e/0x9c
     kasan_report.cold+0x112/0x117
     ? alarm_expires_remaining+0x49/0x70
     __asan_load8+0x86/0xb0
     alarm_expires_remaining+0x49/0x70
     idletimer_tg_show+0xe5/0x19b [xt_IDLETIMER 11219304af9316a21bee5ba9d58f76a6b9bccc6d]
     dev_attr_show+0x3c/0x60
     sysfs_kf_seq_show+0x11d/0x1f0
     ? device_remove_bin_file+0x20/0x20
     kernfs_seq_show+0xa4/0xb0
     seq_read_iter+0x29c/0x750
     kernfs_fop_read_iter+0x25a/0x2c0
     ? __fsnotify_parent+0x3d1/0x570
     ? iov_iter_init+0x70/0x90
     new_sync_read+0x2a7/0x3d0
     ? __x64_sys_llseek+0x230/0x230
     ? rw_verify_area+0x81/0x150
     vfs_read+0x17b/0x240
     ksys_read+0xd9/0x180
     ? vfs_write+0x460/0x460
     ? do_syscall_64+0x16/0xc0
     ? lockdep_hardirqs_on+0x79/0x120
     __x64_sys_read+0x43/0x50
     do_syscall_64+0x3b/0xc0
     entry_SYSCALL_64_after_hwframe+0x44/0xae
    RIP: 0033:0x7f0cdc819142
    Code: c0 e9 c2 fe ff ff 50 48 8d 3d 3a ca 0a 00 e8 f5 19 02 00 0f 1f 44 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 ec 28 48 89 54 24
    RSP: 002b:00007fff28eee5b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
    RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f0cdc819142
    RDX: 0000000000020000 RSI: 00007f0cdc032000 RDI: 0000000000000003
    RBP: 00007f0cdc032000 R08: 00007f0cdc031010 R09: 0000000000000000
    R10: 0000000000000022 R11: 0000000000000246 R12: 00005607e9ee31f0
    R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000

Fixes: 68983a3 ("netfilter: xtables: Add snapshot of hardidletimer target")
Signed-off-by: Juhee Kang <[email protected]>
Reviewed-by: Florian Westphal <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
alistair23 pushed a commit that referenced this issue Nov 2, 2021
On the preemption path when updating a Xen guest's runstate times, this
lock is taken inside the scheduler rq->lock, which is a raw spinlock.
This was shown in a lockdep warning:

[   89.138354] =============================
[   89.138356] [ BUG: Invalid wait context ]
[   89.138358] 5.15.0-rc5+ torvalds#834 Tainted: G S        I E
[   89.138360] -----------------------------
[   89.138361] xen_shinfo_test/2575 is trying to lock:
[   89.138363] ffffa34a0364efd8 (&kvm->arch.pvclock_gtod_sync_lock){....}-{3:3}, at: get_kvmclock_ns+0x1f/0x130 [kvm]
[   89.138442] other info that might help us debug this:
[   89.138444] context-{5:5}
[   89.138445] 4 locks held by xen_shinfo_test/2575:
[   89.138447]  #0: ffff972bdc3b8108 (&vcpu->mutex){+.+.}-{4:4}, at: kvm_vcpu_ioctl+0x77/0x6f0 [kvm]
[   89.138483]  #1: ffffa34a03662e90 (&kvm->srcu){....}-{0:0}, at: kvm_arch_vcpu_ioctl_run+0xdc/0x8b0 [kvm]
[   89.138526]  #2: ffff97331fdbac98 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0xff/0xbd0
[   89.138534]  #3: ffffa34a03662e90 (&kvm->srcu){....}-{0:0}, at: kvm_arch_vcpu_put+0x26/0x170 [kvm]
...
[   89.138695]  get_kvmclock_ns+0x1f/0x130 [kvm]
[   89.138734]  kvm_xen_update_runstate+0x14/0x90 [kvm]
[   89.138783]  kvm_xen_update_runstate_guest+0x15/0xd0 [kvm]
[   89.138830]  kvm_arch_vcpu_put+0xe6/0x170 [kvm]
[   89.138870]  kvm_sched_out+0x2f/0x40 [kvm]
[   89.138900]  __schedule+0x5de/0xbd0

Cc: [email protected]
Reported-by: [email protected]
Fixes: 30b5c85 ("KVM: x86/xen: Add support for vCPU runstate information")
Signed-off-by: David Woodhouse <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
alistair23 pushed a commit that referenced this issue Dec 1, 2021
Often some test cases like btrfs/161 trigger lockdep splats that complain
about possible unsafe lock scenario due to the fact that during mount,
when reading the chunk tree we end up calling blkdev_get_by_path() while
holding a read lock on a leaf of the chunk tree. That produces a lockdep
splat like the following:

[ 3653.683975] ======================================================
[ 3653.685148] WARNING: possible circular locking dependency detected
[ 3653.686301] 5.15.0-rc7-btrfs-next-103 #1 Not tainted
[ 3653.687239] ------------------------------------------------------
[ 3653.688400] mount/447465 is trying to acquire lock:
[ 3653.689320] ffff8c6b0c76e528 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev.part.0+0xe7/0x320
[ 3653.691054]
               but task is already holding lock:
[ 3653.692155] ffff8c6b0a9f39e0 (btrfs-chunk-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x24/0x110 [btrfs]
[ 3653.693978]
               which lock already depends on the new lock.

[ 3653.695510]
               the existing dependency chain (in reverse order) is:
[ 3653.696915]
               -> #3 (btrfs-chunk-00){++++}-{3:3}:
[ 3653.698053]        down_read_nested+0x4b/0x140
[ 3653.698893]        __btrfs_tree_read_lock+0x24/0x110 [btrfs]
[ 3653.699988]        btrfs_read_lock_root_node+0x31/0x40 [btrfs]
[ 3653.701205]        btrfs_search_slot+0x537/0xc00 [btrfs]
[ 3653.702234]        btrfs_insert_empty_items+0x32/0x70 [btrfs]
[ 3653.703332]        btrfs_init_new_device+0x563/0x15b0 [btrfs]
[ 3653.704439]        btrfs_ioctl+0x2110/0x3530 [btrfs]
[ 3653.705405]        __x64_sys_ioctl+0x83/0xb0
[ 3653.706215]        do_syscall_64+0x3b/0xc0
[ 3653.706990]        entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 3653.708040]
               -> #2 (sb_internal#2){.+.+}-{0:0}:
[ 3653.708994]        lock_release+0x13d/0x4a0
[ 3653.709533]        up_write+0x18/0x160
[ 3653.710017]        btrfs_sync_file+0x3f3/0x5b0 [btrfs]
[ 3653.710699]        __loop_update_dio+0xbd/0x170 [loop]
[ 3653.711360]        lo_ioctl+0x3b1/0x8a0 [loop]
[ 3653.711929]        block_ioctl+0x48/0x50
[ 3653.712442]        __x64_sys_ioctl+0x83/0xb0
[ 3653.712991]        do_syscall_64+0x3b/0xc0
[ 3653.713519]        entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 3653.714233]
               -> #1 (&lo->lo_mutex){+.+.}-{3:3}:
[ 3653.715026]        __mutex_lock+0x92/0x900
[ 3653.715648]        lo_open+0x28/0x60 [loop]
[ 3653.716275]        blkdev_get_whole+0x28/0x90
[ 3653.716867]        blkdev_get_by_dev.part.0+0x142/0x320
[ 3653.717537]        blkdev_open+0x5e/0xa0
[ 3653.718043]        do_dentry_open+0x163/0x390
[ 3653.718604]        path_openat+0x3f0/0xa80
[ 3653.719128]        do_filp_open+0xa9/0x150
[ 3653.719652]        do_sys_openat2+0x97/0x160
[ 3653.720197]        __x64_sys_openat+0x54/0x90
[ 3653.720766]        do_syscall_64+0x3b/0xc0
[ 3653.721285]        entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 3653.721986]
               -> #0 (&disk->open_mutex){+.+.}-{3:3}:
[ 3653.722775]        __lock_acquire+0x130e/0x2210
[ 3653.723348]        lock_acquire+0xd7/0x310
[ 3653.723867]        __mutex_lock+0x92/0x900
[ 3653.724394]        blkdev_get_by_dev.part.0+0xe7/0x320
[ 3653.725041]        blkdev_get_by_path+0xb8/0xd0
[ 3653.725614]        btrfs_get_bdev_and_sb+0x1b/0xb0 [btrfs]
[ 3653.726332]        open_fs_devices+0xd7/0x2c0 [btrfs]
[ 3653.726999]        btrfs_read_chunk_tree+0x3ad/0x870 [btrfs]
[ 3653.727739]        open_ctree+0xb8e/0x17bf [btrfs]
[ 3653.728384]        btrfs_mount_root.cold+0x12/0xde [btrfs]
[ 3653.729130]        legacy_get_tree+0x30/0x50
[ 3653.729676]        vfs_get_tree+0x28/0xc0
[ 3653.730192]        vfs_kern_mount.part.0+0x71/0xb0
[ 3653.730800]        btrfs_mount+0x11d/0x3a0 [btrfs]
[ 3653.731427]        legacy_get_tree+0x30/0x50
[ 3653.731970]        vfs_get_tree+0x28/0xc0
[ 3653.732486]        path_mount+0x2d4/0xbe0
[ 3653.732997]        __x64_sys_mount+0x103/0x140
[ 3653.733560]        do_syscall_64+0x3b/0xc0
[ 3653.734080]        entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 3653.734782]
               other info that might help us debug this:

[ 3653.735784] Chain exists of:
                 &disk->open_mutex --> sb_internal#2 --> btrfs-chunk-00

[ 3653.737123]  Possible unsafe locking scenario:

[ 3653.737865]        CPU0                    CPU1
[ 3653.738435]        ----                    ----
[ 3653.739007]   lock(btrfs-chunk-00);
[ 3653.739449]                                lock(sb_internal#2);
[ 3653.740193]                                lock(btrfs-chunk-00);
[ 3653.740955]   lock(&disk->open_mutex);
[ 3653.741431]
                *** DEADLOCK ***

[ 3653.742176] 3 locks held by mount/447465:
[ 3653.742739]  #0: ffff8c6acf85c0e8 (&type->s_umount_key#44/1){+.+.}-{3:3}, at: alloc_super+0xd5/0x3b0
[ 3653.744114]  #1: ffffffffc0b28f70 (uuid_mutex){+.+.}-{3:3}, at: btrfs_read_chunk_tree+0x59/0x870 [btrfs]
[ 3653.745563]  #2: ffff8c6b0a9f39e0 (btrfs-chunk-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x24/0x110 [btrfs]
[ 3653.747066]
               stack backtrace:
[ 3653.747723] CPU: 4 PID: 447465 Comm: mount Not tainted 5.15.0-rc7-btrfs-next-103 #1
[ 3653.748873] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[ 3653.750592] Call Trace:
[ 3653.750967]  dump_stack_lvl+0x57/0x72
[ 3653.751526]  check_noncircular+0xf3/0x110
[ 3653.752136]  ? stack_trace_save+0x4b/0x70
[ 3653.752748]  __lock_acquire+0x130e/0x2210
[ 3653.753356]  lock_acquire+0xd7/0x310
[ 3653.753898]  ? blkdev_get_by_dev.part.0+0xe7/0x320
[ 3653.754596]  ? lock_is_held_type+0xe8/0x140
[ 3653.755125]  ? blkdev_get_by_dev.part.0+0xe7/0x320
[ 3653.755729]  ? blkdev_get_by_dev.part.0+0xe7/0x320
[ 3653.756338]  __mutex_lock+0x92/0x900
[ 3653.756794]  ? blkdev_get_by_dev.part.0+0xe7/0x320
[ 3653.757400]  ? do_raw_spin_unlock+0x4b/0xa0
[ 3653.757930]  ? _raw_spin_unlock+0x29/0x40
[ 3653.758437]  ? bd_prepare_to_claim+0x129/0x150
[ 3653.758999]  ? trace_module_get+0x2b/0xd0
[ 3653.759508]  ? try_module_get.part.0+0x50/0x80
[ 3653.760072]  blkdev_get_by_dev.part.0+0xe7/0x320
[ 3653.760661]  ? devcgroup_check_permission+0xc1/0x1f0
[ 3653.761288]  blkdev_get_by_path+0xb8/0xd0
[ 3653.761797]  btrfs_get_bdev_and_sb+0x1b/0xb0 [btrfs]
[ 3653.762454]  open_fs_devices+0xd7/0x2c0 [btrfs]
[ 3653.763055]  ? clone_fs_devices+0x8f/0x170 [btrfs]
[ 3653.763689]  btrfs_read_chunk_tree+0x3ad/0x870 [btrfs]
[ 3653.764370]  ? kvm_sched_clock_read+0x14/0x40
[ 3653.764922]  open_ctree+0xb8e/0x17bf [btrfs]
[ 3653.765493]  ? super_setup_bdi_name+0x79/0xd0
[ 3653.766043]  btrfs_mount_root.cold+0x12/0xde [btrfs]
[ 3653.766780]  ? rcu_read_lock_sched_held+0x3f/0x80
[ 3653.767488]  ? kfree+0x1f2/0x3c0
[ 3653.767979]  legacy_get_tree+0x30/0x50
[ 3653.768548]  vfs_get_tree+0x28/0xc0
[ 3653.769076]  vfs_kern_mount.part.0+0x71/0xb0
[ 3653.769718]  btrfs_mount+0x11d/0x3a0 [btrfs]
[ 3653.770381]  ? rcu_read_lock_sched_held+0x3f/0x80
[ 3653.771086]  ? kfree+0x1f2/0x3c0
[ 3653.771574]  legacy_get_tree+0x30/0x50
[ 3653.772136]  vfs_get_tree+0x28/0xc0
[ 3653.772673]  path_mount+0x2d4/0xbe0
[ 3653.773201]  __x64_sys_mount+0x103/0x140
[ 3653.773793]  do_syscall_64+0x3b/0xc0
[ 3653.774333]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 3653.775094] RIP: 0033:0x7f648bc45aaa

This happens because through btrfs_read_chunk_tree(), which is called only
during mount, ends up acquiring the mutex open_mutex of a block device
while holding a read lock on a leaf of the chunk tree while other paths
need to acquire other locks before locking extent buffers of the chunk
tree.

Since at mount time when we call btrfs_read_chunk_tree() we know that
we don't have other tasks running in parallel and modifying the chunk
tree, we can simply skip locking of chunk tree extent buffers. So do
that and move the assertion that checks the fs is not yet mounted to the
top block of btrfs_read_chunk_tree(), with a comment before doing it.

Signed-off-by: Filipe Manana <[email protected]>
Signed-off-by: David Sterba <[email protected]>
alistair23 pushed a commit that referenced this issue Dec 22, 2021
There are cases that the TSC clocksource is wrongly judged as unstable by
the clocksource watchdog mechanism which tries to validate the TSC against
HPET, PM_TIMER or jiffies. While there is hardly a general reliable way to
check the validity of a watchdog, Thomas Gleixner proposed [1]:

"I'm inclined to lift that requirement when the CPU has:

    1) X86_FEATURE_CONSTANT_TSC
    2) X86_FEATURE_NONSTOP_TSC
    3) X86_FEATURE_NONSTOP_TSC_S3
    4) X86_FEATURE_TSC_ADJUST
    5) At max. 4 sockets

 After two decades of horrors we're finally at a point where TSC seems
 to be halfway reliable and less abused by BIOS tinkerers. TSC_ADJUST
 was really key as we can now detect even small modifications reliably
 and the important point is that we can cure them as well (not pretty
 but better than all other options)."

As feature #3 X86_FEATURE_NONSTOP_TSC_S3 only exists on several generations
of Atom processorz, and is always coupled with X86_FEATURE_CONSTANT_TSC
and X86_FEATURE_NONSTOP_TSC, skip checking it, and also be more defensive
to use maximal 2 sockets.

The check is done inside tsc_init() before registering 'tsc-early' and
'tsc' clocksources, as there were cases that both of them had been
wrongly judged as unreliable.

For more background of tsc/watchdog, there is a good summary in [2]

[tglx} Update vs. jiffies:

  On systems where the only remaining clocksource aside of TSC is jiffies
  there is no way to make this work because that creates a circular
  dependency. Jiffies accuracy depends on not missing a periodic timer
  interrupt, which is not guaranteed. That could be detected by TSC, but as
  TSC is not trusted this cannot be compensated. The consequence is a
  circulus vitiosus which results in shutting down TSC and falling back to
  the jiffies clocksource which is even more unreliable.

[1]. https://lore.kernel.org/lkml/[email protected]/
[2]. https://lore.kernel.org/lkml/[email protected]/

[ tglx: Refine comment and amend changelog ]

Fixes: 6e3cd95 ("x86/hpet: Use another crystalball to evaluate HPET usability")
Suggested-by: Thomas Gleixner <[email protected]>
Signed-off-by: Feng Tang <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: "Paul E. McKenney" <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
alistair23 pushed a commit that referenced this issue Dec 22, 2021
When branch target identifiers are in use, code reachable via an
indirect branch requires a BTI landing pad at the branch target site.

When building FTRACE_WITH_REGS atop patchable-function-entry, we miss
BTIs at the start start of the `ftrace_caller` and `ftrace_regs_caller`
trampolines, and when these are called from a module via a PLT (which
will use a `BR X16`), we will encounter a BTI failure, e.g.

| # insmod lkdtm.ko
| lkdtm: No crash points registered, enable through debugfs
| # echo function_graph > /sys/kernel/debug/tracing/current_tracer
| # cat /sys/kernel/debug/provoke-crash/DIRECT
| Unhandled 64-bit el1h sync exception on CPU0, ESR 0x34000001 -- BTI
| CPU: 0 PID: 174 Comm: cat Not tainted 5.16.0-rc2-dirty #3
| Hardware name: linux,dummy-virt (DT)
| pstate: 60400405 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=jc)
| pc : ftrace_caller+0x0/0x3c
| lr : lkdtm_debugfs_open+0xc/0x20 [lkdtm]
| sp : ffff800012e43b00
| x29: ffff800012e43b00 x28: 0000000000000000 x27: ffff800012e43c88
| x26: 0000000000000000 x25: 0000000000000000 x24: ffff0000c171f200
| x23: ffff0000c27b1e00 x22: ffff0000c2265240 x21: ffff0000c23c8c30
| x20: ffff8000090ba380 x19: 0000000000000000 x18: 0000000000000000
| x17: 0000000000000000 x16: ffff80001002bb4c x15: 0000000000000000
| x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000900ff0
| x11: ffff0000c4166310 x10: ffff800012e43b00 x9 : ffff8000104f2384
| x8 : 0000000000000001 x7 : 0000000000000000 x6 : 000000000000003f
| x5 : 0000000000000040 x4 : ffff800012e43af0 x3 : 0000000000000001
| x2 : ffff8000090b0000 x1 : ffff0000c171f200 x0 : ffff0000c23c8c30
| Kernel panic - not syncing: Unhandled exception
| CPU: 0 PID: 174 Comm: cat Not tainted 5.16.0-rc2-dirty #3
| Hardware name: linux,dummy-virt (DT)
| Call trace:
|  dump_backtrace+0x0/0x1a4
|  show_stack+0x24/0x30
|  dump_stack_lvl+0x68/0x84
|  dump_stack+0x1c/0x38
|  panic+0x168/0x360
|  arm64_exit_nmi.isra.0+0x0/0x80
|  el1h_64_sync_handler+0x68/0xd4
|  el1h_64_sync+0x78/0x7c
|  ftrace_caller+0x0/0x3c
|  do_dentry_open+0x134/0x3b0
|  vfs_open+0x38/0x44
|  path_openat+0x89c/0xe40
|  do_filp_open+0x8c/0x13c
|  do_sys_openat2+0xbc/0x174
|  __arm64_sys_openat+0x6c/0xbc
|  invoke_syscall+0x50/0x120
|  el0_svc_common.constprop.0+0xdc/0x100
|  do_el0_svc+0x84/0xa0
|  el0_svc+0x28/0x80
|  el0t_64_sync_handler+0xa8/0x130
|  el0t_64_sync+0x1a0/0x1a4
| SMP: stopping secondary CPUs
| Kernel Offset: disabled
| CPU features: 0x0,00000f42,da660c5f
| Memory Limit: none
| ---[ end Kernel panic - not syncing: Unhandled exception ]---

Fix this by adding the required `BTI C`, as we only require these to be
reachable via BL for direct calls or BR X16/X17 for PLTs. For now, these
are open-coded in the function prologue, matching the style of the
`__hwasan_tag_mismatch` trampoline.

In future we may wish to consider adding a new SYM_CODE_START_*()
variant which has an implicit BTI.

When ftrace is built atop mcount, the trampolines are marked with
SYM_FUNC_START(), and so get an implicit BTI. We may need to change
these over to SYM_CODE_START() in future for RELIABLE_STACKTRACE, in
case we need to apply special care aroud the return address being
rewritten.

Fixes: 97fed77 ("arm64: bti: Provide Kconfig for kernel mode BTI")
Signed-off-by: Mark Rutland <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Mark Brown <[email protected]>
Cc: Will Deacon <[email protected]>
Reviewed-by: Mark Brown <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>
alistair23 pushed a commit that referenced this issue Dec 22, 2021
The first commit cited below attempts to fix the off-by-one error that
appeared in some comparisons with an open range. Due to this error,
arithmetically equivalent pieces of code could get different verdicts
from the verifier, for example (pseudocode):

  // 1. Passes the verifier:
  if (data + 8 > data_end)
      return early
  read *(u64 *)data, i.e. [data; data+7]

  // 2. Rejected by the verifier (should still pass):
  if (data + 7 >= data_end)
      return early
  read *(u64 *)data, i.e. [data; data+7]

The attempted fix, however, shifts the range by one in a wrong
direction, so the bug not only remains, but also such piece of code
starts failing in the verifier:

  // 3. Rejected by the verifier, but the check is stricter than in #1.
  if (data + 8 >= data_end)
      return early
  read *(u64 *)data, i.e. [data; data+7]

The change performed by that fix converted an off-by-one bug into
off-by-two. The second commit cited below added the BPF selftests
written to ensure than code chunks like #3 are rejected, however,
they should be accepted.

This commit fixes the off-by-two error by adjusting new_range in the
right direction and fixes the tests by changing the range into the
one that should actually fail.

Fixes: fb2a311 ("bpf: fix off by one for range markings with L{T, E} patterns")
Fixes: b37242c ("bpf: add test cases to bpf selftests to cover all access tests")
Signed-off-by: Maxim Mikityanskiy <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]
alistair23 pushed a commit that referenced this issue Dec 22, 2021
Line 1169 (#3) allocates a memory chunk for victim_name by kmalloc(),
but  when the function returns in line 1184 (#4) victim_name allocated
by line 1169 (#3) is not freed, which will lead to a memory leak.
There is a similar snippet of code in this function as allocating a memory
chunk for victim_name in line 1104 (#1) as well as releasing the memory
in line 1116 (#2).

We should kfree() victim_name when the return value of backref_in_log()
is less than zero and before the function returns in line 1184 (#4).

1057 static inline int __add_inode_ref(struct btrfs_trans_handle *trans,
1058 				  struct btrfs_root *root,
1059 				  struct btrfs_path *path,
1060 				  struct btrfs_root *log_root,
1061 				  struct btrfs_inode *dir,
1062 				  struct btrfs_inode *inode,
1063 				  u64 inode_objectid, u64 parent_objectid,
1064 				  u64 ref_index, char *name, int namelen,
1065 				  int *search_done)
1066 {

1104 	victim_name = kmalloc(victim_name_len, GFP_NOFS);
	// #1: kmalloc (victim_name-1)
1105 	if (!victim_name)
1106 		return -ENOMEM;

1112	ret = backref_in_log(log_root, &search_key,
1113			parent_objectid, victim_name,
1114			victim_name_len);
1115	if (ret < 0) {
1116		kfree(victim_name); // #2: kfree (victim_name-1)
1117		return ret;
1118	} else if (!ret) {

1169 	victim_name = kmalloc(victim_name_len, GFP_NOFS);
	// #3: kmalloc (victim_name-2)
1170 	if (!victim_name)
1171 		return -ENOMEM;

1180 	ret = backref_in_log(log_root, &search_key,
1181 			parent_objectid, victim_name,
1182 			victim_name_len);
1183 	if (ret < 0) {
1184 		return ret; // #4: missing kfree (victim_name-2)
1185 	} else if (!ret) {

1241 	return 0;
1242 }

Fixes: d3316c8 ("btrfs: Properly handle backref_in_log retval")
CC: [email protected] # 5.10+
Reviewed-by: Qu Wenruo <[email protected]>
Reviewed-by: Filipe Manana <[email protected]>
Signed-off-by: Jianglei Nie <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
alistair23 pushed a commit that referenced this issue Oct 2, 2022
Because rxrpc pretends to be a tunnel on top of a UDP/UDP6 socket, allowing
it to siphon off UDP packets early in the handling of received UDP packets
thereby avoiding the packet going through the UDP receive queue, it doesn't
get ICMP packets through the UDP ->sk_error_report() callback.  In fact, it
doesn't appear that there's any usable option for getting hold of ICMP
packets.

Fix this by adding a new UDP encap hook to distribute error messages for
UDP tunnels.  If the hook is set, then the tunnel driver will be able to
see ICMP packets.  The hook provides the offset into the packet of the UDP
header of the original packet that caused the notification.

An alternative would be to call the ->error_handler() hook - but that
requires that the skbuff be cloned (as ip_icmp_error() or ipv6_cmp_error()
do, though isn't really necessary or desirable in rxrpc's case is we want
to parse them there and then, not queue them).

Changes
=======
ver #3)
 - Fixed an uninitialised variable.

ver #2)
 - Fixed some missing CONFIG_AF_RXRPC_IPV6 conditionals.

Fixes: 5271953 ("rxrpc: Use the UDP encap_rcv hook")
Signed-off-by: David Howells <[email protected]>
alistair23 pushed a commit that referenced this issue Oct 2, 2022
The SRv6 layer allows defining HMAC data that can later be used to sign IPv6
Segment Routing Headers. This configuration is realised via netlink through
four attributes: SEG6_ATTR_HMACKEYID, SEG6_ATTR_SECRET, SEG6_ATTR_SECRETLEN and
SEG6_ATTR_ALGID. Because the SECRETLEN attribute is decoupled from the actual
length of the SECRET attribute, it is possible to provide invalid combinations
(e.g., secret = "", secretlen = 64). This case is not checked in the code and
with an appropriately crafted netlink message, an out-of-bounds read of up
to 64 bytes (max secret length) can occur past the skb end pointer and into
skb_shared_info:

Breakpoint 1, seg6_genl_sethmac (skb=<optimized out>, info=<optimized out>) at net/ipv6/seg6.c:208
208		memcpy(hinfo->secret, secret, slen);
(gdb) bt
 #0  seg6_genl_sethmac (skb=<optimized out>, info=<optimized out>) at net/ipv6/seg6.c:208
 #1  0xffffffff81e012e9 in genl_family_rcv_msg_doit (skb=skb@entry=0xffff88800b1f9f00, nlh=nlh@entry=0xffff88800b1b7600,
    extack=extack@entry=0xffffc90000ba7af0, ops=ops@entry=0xffffc90000ba7a80, hdrlen=4, net=0xffffffff84237580 <init_net>, family=<optimized out>,
    family=<optimized out>) at net/netlink/genetlink.c:731
 #2  0xffffffff81e01435 in genl_family_rcv_msg (extack=0xffffc90000ba7af0, nlh=0xffff88800b1b7600, skb=0xffff88800b1f9f00,
    family=0xffffffff82fef6c0 <seg6_genl_family>) at net/netlink/genetlink.c:775
 #3  genl_rcv_msg (skb=0xffff88800b1f9f00, nlh=0xffff88800b1b7600, extack=0xffffc90000ba7af0) at net/netlink/genetlink.c:792
 #4  0xffffffff81dfffc3 in netlink_rcv_skb (skb=skb@entry=0xffff88800b1f9f00, cb=cb@entry=0xffffffff81e01350 <genl_rcv_msg>)
    at net/netlink/af_netlink.c:2501
 #5  0xffffffff81e00919 in genl_rcv (skb=0xffff88800b1f9f00) at net/netlink/genetlink.c:803
 #6  0xffffffff81dff6ae in netlink_unicast_kernel (ssk=0xffff888010eec800, skb=0xffff88800b1f9f00, sk=0xffff888004aed000)
    at net/netlink/af_netlink.c:1319
 torvalds#7  netlink_unicast (ssk=ssk@entry=0xffff888010eec800, skb=skb@entry=0xffff88800b1f9f00, portid=portid@entry=0, nonblock=<optimized out>)
    at net/netlink/af_netlink.c:1345
 torvalds#8  0xffffffff81dff9a4 in netlink_sendmsg (sock=<optimized out>, msg=0xffffc90000ba7e48, len=<optimized out>) at net/netlink/af_netlink.c:1921
...
(gdb) p/x ((struct sk_buff *)0xffff88800b1f9f00)->head + ((struct sk_buff *)0xffff88800b1f9f00)->end
$1 = 0xffff88800b1b76c0
(gdb) p/x secret
$2 = 0xffff88800b1b76c0
(gdb) p slen
$3 = 64 '@'

The OOB data can then be read back from userspace by dumping HMAC state. This
commit fixes this by ensuring SECRETLEN cannot exceed the actual length of
SECRET.

Reported-by: Lucas Leong <[email protected]>
Tested: verified that EINVAL is correctly returned when secretlen > len(secret)
Fixes: 4f4853d ("ipv6: sr: implement API to control SR HMAC structure")
Signed-off-by: David Lebrun <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
alistair23 pushed a commit that referenced this issue Oct 2, 2022
During stress testing with CONFIG_SMP disabled, KASAN reports as below:

==================================================================
BUG: KASAN: use-after-free in __mutex_lock+0xe5/0xc30
Read of size 8 at addr ffff8881094223f8 by task stress/7789

CPU: 0 PID: 7789 Comm: stress Not tainted 6.0.0-rc1-00002-g0d53d2e882f9 #3
Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
Call Trace:
 <TASK>
..
 __mutex_lock+0xe5/0xc30
..
 z_erofs_do_read_page+0x8ce/0x1560
..
 z_erofs_readahead+0x31c/0x580
..
Freed by task 7787
 kasan_save_stack+0x1e/0x40
 kasan_set_track+0x20/0x30
 kasan_set_free_info+0x20/0x40
 __kasan_slab_free+0x10c/0x190
 kmem_cache_free+0xed/0x380
 rcu_core+0x3d5/0xc90
 __do_softirq+0x12d/0x389

Last potentially related work creation:
 kasan_save_stack+0x1e/0x40
 __kasan_record_aux_stack+0x97/0xb0
 call_rcu+0x3d/0x3f0
 erofs_shrink_workstation+0x11f/0x210
 erofs_shrink_scan+0xdc/0x170
 shrink_slab.constprop.0+0x296/0x530
 drop_slab+0x1c/0x70
 drop_caches_sysctl_handler+0x70/0x80
 proc_sys_call_handler+0x20a/0x2f0
 vfs_write+0x555/0x6c0
 ksys_write+0xbe/0x160
 do_syscall_64+0x3b/0x90

The root cause is that erofs_workgroup_unfreeze() doesn't reset to
orig_val thus it causes a race that the pcluster reuses unexpectedly
before freeing.

Since UP platforms are quite rare now, such path becomes unnecessary.
Let's drop such specific-designed path directly instead.

Fixes: 73f5c66 ("staging: erofs: fix `erofs_workgroup_{try_to_freeze, unfreeze}'")
Reviewed-by: Yue Hu <[email protected]>
Reviewed-by: Chao Yu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Gao Xiang <[email protected]>
alistair23 pushed a commit that referenced this issue Oct 2, 2022
Since commit:

  47546a1 ("arm64: mm: install KPTI nG mappings with MMU enabled)"

... when building with CONFIG_DEBUG_ATOMIC_SLEEP=y and booting under
QEMU TCG with '-cpu max', there's a boot-time splat:

| BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580
| in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 15, name: migration/0
| preempt_count: 1, expected: 0
| RCU nest depth: 0, expected: 0
| no locks held by migration/0/15.
| irq event stamp: 28
| hardirqs last  enabled at (27): [<ffff8000091ed180>] _raw_spin_unlock_irq+0x3c/0x7c
| hardirqs last disabled at (28): [<ffff8000081b8d74>] multi_cpu_stop+0x150/0x18c
| softirqs last  enabled at (0): [<ffff80000809a314>] copy_process+0x594/0x1964
| softirqs last disabled at (0): [<0000000000000000>] 0x0
| CPU: 0 PID: 15 Comm: migration/0 Not tainted 6.0.0-rc3-00002-g419b42ff7eef #3
| Hardware name: linux,dummy-virt (DT)
| Stopper: multi_cpu_stop+0x0/0x18c <- stop_cpus.constprop.0+0xa0/0xfc
| Call trace:
|  dump_backtrace.part.0+0xd0/0xe0
|  show_stack+0x1c/0x5c
|  dump_stack_lvl+0x88/0xb4
|  dump_stack+0x1c/0x38
|  __might_resched+0x180/0x230
|  __might_sleep+0x4c/0xa0
|  __mutex_lock+0x5c/0x450
|  mutex_lock_nested+0x30/0x40
|  create_kpti_ng_temp_pgd+0x4fc/0x6d0
|  kpti_install_ng_mappings+0x2b8/0x3b0
|  cpu_enable_non_boot_scope_capabilities+0x7c/0xd0
|  multi_cpu_stop+0xa0/0x18c
|  cpu_stopper_thread+0x88/0x11c
|  smpboot_thread_fn+0x1ec/0x290
|  kthread+0x118/0x120
|  ret_from_fork+0x10/0x20

Since commit:

  ee017ee ("arm64/mm: avoid fixmap race condition when create pud mapping")

... once the kernel leave the SYSTEM_BOOTING state, the fixmap pagetable
entries are protected by the fixmap_lock mutex.

The new KPTI rewrite code uses __create_pgd_mapping() to create a
temporary pagetable. This happens in atomic context, after secondary
CPUs are brought up and the kernel has left the SYSTEM_BOOTING state.
Hence we try to acquire a mutex in atomic context, which is generally
unsound (though benign in this case as the mutex should be free and all
other CPUs are quiescent).

This patch avoids the issue by pulling the mutex out of alloc_init_pud()
and calling it at a higher level in the pagetable manipulation code.
This allows it to be used without locking where one CPU is known to be
in exclusive control of the machine, even after having left the
SYSTEM_BOOTING state.

Fixes: 47546a1 ("arm64: mm: install KPTI nG mappings with MMU enabled")
Signed-off-by: Mark Rutland <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Will Deacon <[email protected]>
Reviewed-by: Ard Biesheuvel <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>
alistair23 pushed a commit that referenced this issue Nov 3, 2022
With lockdeps enabled, we get the following warning:

======================================================
WARNING: possible circular locking dependency detected
------------------------------------------------------
kworker/u12:1/53 is trying to acquire lock:
ffff80000adce220 (coresight_mutex){+.+.}-{4:4}, at: coresight_set_assoc_ectdev_mutex+0x3c/0x5c
but task is already holding lock:
ffff80000add1f60 (ect_mutex){+.+.}-{4:4}, at: cti_probe+0x318/0x394

which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:

-> #1 (ect_mutex){+.+.}-{4:4}:
       __mutex_lock_common+0xd8/0xe60
       mutex_lock_nested+0x44/0x50
       cti_add_assoc_to_csdev+0x4c/0x184
       coresight_register+0x2f0/0x314
       tmc_probe+0x33c/0x414

-> #0 (coresight_mutex){+.+.}-{4:4}:
       __lock_acquire+0x1a20/0x32d0
       lock_acquire+0x160/0x308
       __mutex_lock_common+0xd8/0xe60
       mutex_lock_nested+0x44/0x50
       coresight_set_assoc_ectdev_mutex+0x3c/0x5c
       cti_update_conn_xrefs+0x6c/0xf8
       cti_probe+0x33c/0x394

other info that might help us debug this:
 Possible unsafe locking scenario:
       CPU0                    CPU1
       ----                    ----
  lock(ect_mutex);
                               lock(coresight_mutex);
                               lock(ect_mutex);
  lock(coresight_mutex);
 *** DEADLOCK ***

4 locks held by kworker/u12:1/53:
 #0: ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1fc/0x63c
 #1: (deferred_probe_work){+.+.}-{0:0}, at: process_one_work+0x228/0x63c
 #2: (&dev->mutex){....}-{4:4}, at: __device_attach+0x48/0x1a8
 #3: (ect_mutex){+.+.}-{4:4}, at: cti_probe+0x318/0x394

To fix the same, call cti_add_assoc_to_csdev without the holding
coresight_mutex and confine the locking while setting the associated
ect / cti device using coresight_set_assoc_ectdev_mutex().

Fixes: 177af82 ("coresight: cti: Enable CTI associated with devices")
Cc: Mathieu Poirier <[email protected]>
Cc: Suzuki K Poulose <[email protected]>
Cc: Mike Leach <[email protected]>
Cc: Leo Yan <[email protected]>
Signed-off-by: Sudeep Holla <[email protected]>
Reviewed-by: Mike Leach <[email protected]>
Signed-off-by: Suzuki K Poulose <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
alistair23 pushed a commit that referenced this issue Nov 11, 2022
Sabrina Dubroca says:

====================
macsec: offload-related fixes

I'm working on a dummy offload for macsec on netdevsim. It just has a
small SecY and RXSC table so I can trigger failures easily on the
ndo_* side. It has exposed a couple of issues.

The first patch is a revert of commit c850240 ("net: macsec:
report real_dev features when HW offloading is enabled"). That commit
tried to improve the performance of macsec offload by taking advantage
of some of the NIC's features, but in doing so, broke macsec offload
when the lower device supports both macsec and ipsec offload, as the
ipsec offload feature flags were copied from the real device. Since
the macsec device doesn't provide xdo_* ops, the XFRM core rejects the
registration of the new macsec device in xfrm_api_check.

I'm working on re-adding those feature flags when offload is
available, but I haven't fully solved that yet. I think it would be
safer to do that second part in net-next considering how complex
feature interactions tend to be.

v2:
 - better describe the issue introduced by commit c850240 (Leon
   Romanovsky)
 - patch #3: drop unnecessary !! (Leon Romanovsky)

v3:
 - patch #3: drop extra newline (Jakub Kicinski)
====================

Signed-off-by: David S. Miller <[email protected]>
alistair23 pushed a commit that referenced this issue Nov 11, 2022
Yang Yingliang says:

====================
stmmac: dwmac-loongson: fixes three leaks

patch #2 fixes missing pci_disable_device() in the error path in probe()
patch #1 and pach #3 fix missing pci_disable_msi() and of_node_put() in
error and remove() path.
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>
alistair23 pushed a commit that referenced this issue Dec 11, 2022
Syzbot reported the following lockdep splat

======================================================
WARNING: possible circular locking dependency detected
6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0 Not tainted
------------------------------------------------------
syz-executor307/3029 is trying to acquire lock:
ffff0000c02525d8 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0x54/0xb4 mm/memory.c:5576

but task is already holding lock:
ffff0000c958a608 (btrfs-root-00){++++}-{3:3}, at: __btrfs_tree_read_lock fs/btrfs/locking.c:134 [inline]
ffff0000c958a608 (btrfs-root-00){++++}-{3:3}, at: btrfs_tree_read_lock fs/btrfs/locking.c:140 [inline]
ffff0000c958a608 (btrfs-root-00){++++}-{3:3}, at: btrfs_read_lock_root_node+0x13c/0x1c0 fs/btrfs/locking.c:279

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #3 (btrfs-root-00){++++}-{3:3}:
       down_read_nested+0x64/0x84 kernel/locking/rwsem.c:1624
       __btrfs_tree_read_lock fs/btrfs/locking.c:134 [inline]
       btrfs_tree_read_lock fs/btrfs/locking.c:140 [inline]
       btrfs_read_lock_root_node+0x13c/0x1c0 fs/btrfs/locking.c:279
       btrfs_search_slot_get_root+0x74/0x338 fs/btrfs/ctree.c:1637
       btrfs_search_slot+0x1b0/0xfd8 fs/btrfs/ctree.c:1944
       btrfs_update_root+0x6c/0x5a0 fs/btrfs/root-tree.c:132
       commit_fs_roots+0x1f0/0x33c fs/btrfs/transaction.c:1459
       btrfs_commit_transaction+0x89c/0x12d8 fs/btrfs/transaction.c:2343
       flush_space+0x66c/0x738 fs/btrfs/space-info.c:786
       btrfs_async_reclaim_metadata_space+0x43c/0x4e0 fs/btrfs/space-info.c:1059
       process_one_work+0x2d8/0x504 kernel/workqueue.c:2289
       worker_thread+0x340/0x610 kernel/workqueue.c:2436
       kthread+0x12c/0x158 kernel/kthread.c:376
       ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860

-> #2 (&fs_info->reloc_mutex){+.+.}-{3:3}:
       __mutex_lock_common+0xd4/0xca8 kernel/locking/mutex.c:603
       __mutex_lock kernel/locking/mutex.c:747 [inline]
       mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
       btrfs_record_root_in_trans fs/btrfs/transaction.c:516 [inline]
       start_transaction+0x248/0x944 fs/btrfs/transaction.c:752
       btrfs_start_transaction+0x34/0x44 fs/btrfs/transaction.c:781
       btrfs_create_common+0xf0/0x1b4 fs/btrfs/inode.c:6651
       btrfs_create+0x8c/0xb0 fs/btrfs/inode.c:6697
       lookup_open fs/namei.c:3413 [inline]
       open_last_lookups fs/namei.c:3481 [inline]
       path_openat+0x804/0x11c4 fs/namei.c:3688
       do_filp_open+0xdc/0x1b8 fs/namei.c:3718
       do_sys_openat2+0xb8/0x22c fs/open.c:1313
       do_sys_open fs/open.c:1329 [inline]
       __do_sys_openat fs/open.c:1345 [inline]
       __se_sys_openat fs/open.c:1340 [inline]
       __arm64_sys_openat+0xb0/0xe0 fs/open.c:1340
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
       el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206
       el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

-> #1 (sb_internal#2){.+.+}-{0:0}:
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1826 [inline]
       sb_start_intwrite include/linux/fs.h:1948 [inline]
       start_transaction+0x360/0x944 fs/btrfs/transaction.c:683
       btrfs_join_transaction+0x30/0x40 fs/btrfs/transaction.c:795
       btrfs_dirty_inode+0x50/0x140 fs/btrfs/inode.c:6103
       btrfs_update_time+0x1c0/0x1e8 fs/btrfs/inode.c:6145
       inode_update_time fs/inode.c:1872 [inline]
       touch_atime+0x1f0/0x4a8 fs/inode.c:1945
       file_accessed include/linux/fs.h:2516 [inline]
       btrfs_file_mmap+0x50/0x88 fs/btrfs/file.c:2407
       call_mmap include/linux/fs.h:2192 [inline]
       mmap_region+0x7fc/0xc14 mm/mmap.c:1752
       do_mmap+0x644/0x97c mm/mmap.c:1540
       vm_mmap_pgoff+0xe8/0x1d0 mm/util.c:552
       ksys_mmap_pgoff+0x1cc/0x278 mm/mmap.c:1586
       __do_sys_mmap arch/arm64/kernel/sys.c:28 [inline]
       __se_sys_mmap arch/arm64/kernel/sys.c:21 [inline]
       __arm64_sys_mmap+0x58/0x6c arch/arm64/kernel/sys.c:21
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
       el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206
       el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

-> #0 (&mm->mmap_lock){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3095 [inline]
       check_prevs_add kernel/locking/lockdep.c:3214 [inline]
       validate_chain kernel/locking/lockdep.c:3829 [inline]
       __lock_acquire+0x1530/0x30a4 kernel/locking/lockdep.c:5053
       lock_acquire+0x100/0x1f8 kernel/locking/lockdep.c:5666
       __might_fault+0x7c/0xb4 mm/memory.c:5577
       _copy_to_user include/linux/uaccess.h:134 [inline]
       copy_to_user include/linux/uaccess.h:160 [inline]
       btrfs_ioctl_get_subvol_rootref+0x3a8/0x4bc fs/btrfs/ioctl.c:3203
       btrfs_ioctl+0xa08/0xa64 fs/btrfs/ioctl.c:5556
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:870 [inline]
       __se_sys_ioctl fs/ioctl.c:856 [inline]
       __arm64_sys_ioctl+0xd0/0x140 fs/ioctl.c:856
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
       el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206
       el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

other info that might help us debug this:

Chain exists of:
  &mm->mmap_lock --> &fs_info->reloc_mutex --> btrfs-root-00

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(btrfs-root-00);
                               lock(&fs_info->reloc_mutex);
                               lock(btrfs-root-00);
  lock(&mm->mmap_lock);

 *** DEADLOCK ***

1 lock held by syz-executor307/3029:
 #0: ffff0000c958a608 (btrfs-root-00){++++}-{3:3}, at: __btrfs_tree_read_lock fs/btrfs/locking.c:134 [inline]
 #0: ffff0000c958a608 (btrfs-root-00){++++}-{3:3}, at: btrfs_tree_read_lock fs/btrfs/locking.c:140 [inline]
 #0: ffff0000c958a608 (btrfs-root-00){++++}-{3:3}, at: btrfs_read_lock_root_node+0x13c/0x1c0 fs/btrfs/locking.c:279

stack backtrace:
CPU: 0 PID: 3029 Comm: syz-executor307 Not tainted 6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/30/2022
Call trace:
 dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:156
 show_stack+0x2c/0x54 arch/arm64/kernel/stacktrace.c:163
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x104/0x16c lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 print_circular_bug+0x2c4/0x2c8 kernel/locking/lockdep.c:2053
 check_noncircular+0x14c/0x154 kernel/locking/lockdep.c:2175
 check_prev_add kernel/locking/lockdep.c:3095 [inline]
 check_prevs_add kernel/locking/lockdep.c:3214 [inline]
 validate_chain kernel/locking/lockdep.c:3829 [inline]
 __lock_acquire+0x1530/0x30a4 kernel/locking/lockdep.c:5053
 lock_acquire+0x100/0x1f8 kernel/locking/lockdep.c:5666
 __might_fault+0x7c/0xb4 mm/memory.c:5577
 _copy_to_user include/linux/uaccess.h:134 [inline]
 copy_to_user include/linux/uaccess.h:160 [inline]
 btrfs_ioctl_get_subvol_rootref+0x3a8/0x4bc fs/btrfs/ioctl.c:3203
 btrfs_ioctl+0xa08/0xa64 fs/btrfs/ioctl.c:5556
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0xd0/0x140 fs/ioctl.c:856
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
 el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

We do generally the right thing here, copying the references into a
temporary buffer, however we are still holding the path when we do
copy_to_user from the temporary buffer.  Fix this by freeing the path
before we copy to user space.

Reported-by: [email protected]
CC: [email protected] # 4.19+
Reviewed-by: Anand Jain <[email protected]>
Signed-off-by: Josef Bacik <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
alistair23 pushed a commit that referenced this issue Dec 11, 2022
ldev->lock is used to serialize lag change operations. Since multiport
eswtich functionality was added, we now change the mode dynamically.
However, acquiring ldev->lock is not allowed as it could possibly lead
to a deadlock as reported by the lockdep mechanism.

[  836.154963] WARNING: possible circular locking dependency detected
[  836.155850] 5.19.0-rc5_net_56b7df2 #1 Not tainted
[  836.156549] ------------------------------------------------------
[  836.157418] handler1/12198 is trying to acquire lock:
[  836.158178] ffff888187d52b58 (&ldev->lock){+.+.}-{3:3}, at: mlx5_lag_do_mirred+0x3b/0x70 [mlx5_core]
[  836.159575]
[  836.159575] but task is already holding lock:
[  836.160474] ffff8881d4de2930 (&block->cb_lock){++++}-{3:3}, at: tc_setup_cb_add+0x5b/0x200
[  836.161669] which lock already depends on the new lock.
[  836.162905]
[  836.162905] the existing dependency chain (in reverse order) is:
[  836.164008] -> #3 (&block->cb_lock){++++}-{3:3}:
[  836.164946]        down_write+0x25/0x60
[  836.165548]        tcf_block_get_ext+0x1c6/0x5d0
[  836.166253]        ingress_init+0x74/0xa0 [sch_ingress]
[  836.167028]        qdisc_create.constprop.0+0x130/0x5e0
[  836.167805]        tc_modify_qdisc+0x481/0x9f0
[  836.168490]        rtnetlink_rcv_msg+0x16e/0x5a0
[  836.169189]        netlink_rcv_skb+0x4e/0xf0
[  836.169861]        netlink_unicast+0x190/0x250
[  836.170543]        netlink_sendmsg+0x243/0x4b0
[  836.171226]        sock_sendmsg+0x33/0x40
[  836.171860]        ____sys_sendmsg+0x1d1/0x1f0
[  836.172535]        ___sys_sendmsg+0xab/0xf0
[  836.173183]        __sys_sendmsg+0x51/0x90
[  836.173836]        do_syscall_64+0x3d/0x90
[  836.174471]        entry_SYSCALL_64_after_hwframe+0x46/0xb0
[  836.175282]

[  836.175282] -> #2 (rtnl_mutex){+.+.}-{3:3}:
[  836.176190]        __mutex_lock+0x6b/0xf80
[  836.176830]        register_netdevice_notifier+0x21/0x120
[  836.177631]        rtnetlink_init+0x2d/0x1e9
[  836.178289]        netlink_proto_init+0x163/0x179
[  836.178994]        do_one_initcall+0x63/0x300
[  836.179672]        kernel_init_freeable+0x2cb/0x31b
[  836.180403]        kernel_init+0x17/0x140
[  836.181035]        ret_from_fork+0x1f/0x30

 [  836.181687] -> #1 (pernet_ops_rwsem){+.+.}-{3:3}:
[  836.182628]        down_write+0x25/0x60
[  836.183235]        unregister_netdevice_notifier+0x1c/0xb0
[  836.184029]        mlx5_ib_roce_cleanup+0x94/0x120 [mlx5_ib]
[  836.184855]        __mlx5_ib_remove+0x35/0x60 [mlx5_ib]
[  836.185637]        mlx5_eswitch_unregister_vport_reps+0x22f/0x440 [mlx5_core]
[  836.186698]        auxiliary_bus_remove+0x18/0x30
[  836.187409]        device_release_driver_internal+0x1f6/0x270
[  836.188253]        bus_remove_device+0xef/0x160
[  836.188939]        device_del+0x18b/0x3f0
[  836.189562]        mlx5_rescan_drivers_locked+0xd6/0x2d0 [mlx5_core]
[  836.190516]        mlx5_lag_remove_devices+0x69/0xe0 [mlx5_core]
[  836.191414]        mlx5_do_bond_work+0x441/0x620 [mlx5_core]
[  836.192278]        process_one_work+0x25c/0x590
[  836.192963]        worker_thread+0x4f/0x3d0
[  836.193609]        kthread+0xcb/0xf0
[  836.194189]        ret_from_fork+0x1f/0x30

[  836.194826] -> #0 (&ldev->lock){+.+.}-{3:3}:
[  836.195734]        __lock_acquire+0x15b8/0x2a10
[  836.196426]        lock_acquire+0xce/0x2d0
[  836.197057]        __mutex_lock+0x6b/0xf80
[  836.197708]        mlx5_lag_do_mirred+0x3b/0x70 [mlx5_core]
[  836.198575]        tc_act_parse_mirred+0x25b/0x800 [mlx5_core]
[  836.199467]        parse_tc_actions+0x168/0x5a0 [mlx5_core]
[  836.200340]        __mlx5e_add_fdb_flow+0x263/0x480 [mlx5_core]
[  836.201241]        mlx5e_configure_flower+0x8a0/0x1820 [mlx5_core]
[  836.202187]        tc_setup_cb_add+0xd7/0x200
[  836.202856]        fl_hw_replace_filter+0x14c/0x1f0 [cls_flower]
[  836.203739]        fl_change+0xbbe/0x1730 [cls_flower]
[  836.204501]        tc_new_tfilter+0x407/0xd90
[  836.205168]        rtnetlink_rcv_msg+0x406/0x5a0
[  836.205877]        netlink_rcv_skb+0x4e/0xf0
[  836.206535]        netlink_unicast+0x190/0x250
[  836.207217]        netlink_sendmsg+0x243/0x4b0
[  836.207915]        sock_sendmsg+0x33/0x40
[  836.208538]        ____sys_sendmsg+0x1d1/0x1f0
[  836.209219]        ___sys_sendmsg+0xab/0xf0
[  836.209878]        __sys_sendmsg+0x51/0x90
[  836.210510]        do_syscall_64+0x3d/0x90
[  836.211137]        entry_SYSCALL_64_after_hwframe+0x46/0xb0

[  836.211954] other info that might help us debug this:
[  836.213174] Chain exists of:
[  836.213174]   &ldev->lock --> rtnl_mutex --> &block->cb_lock
   836.214650]  Possible unsafe locking scenario:
[  836.214650]
[  836.215574]        CPU0                    CPU1
[  836.216255]        ----                    ----
[  836.216943]   lock(&block->cb_lock);
[  836.217518]                                lock(rtnl_mutex);
[  836.218348]                                lock(&block->cb_lock);
[  836.219212]   lock(&ldev->lock);
[  836.219758]
[  836.219758]  *** DEADLOCK ***
[  836.219758]
 [  836.220747] 2 locks held by handler1/12198:
[  836.221390]  #0: ffff8881d4de2930 (&block->cb_lock){++++}-{3:3}, at: tc_setup_cb_add+0x5b/0x200
[  836.222646]  #1: ffff88810c9a92c0 (&esw->mode_lock){++++}-{3:3}, at: mlx5_esw_hold+0x39/0x50 [mlx5_core]

[  836.224063] stack backtrace:
[  836.224799] CPU: 6 PID: 12198 Comm: handler1 Not tainted 5.19.0-rc5_net_56b7df2 #1
[  836.225923] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[  836.227476] Call Trace:
[  836.227929]  <TASK>
[  836.228332]  dump_stack_lvl+0x57/0x7d
[  836.228924]  check_noncircular+0x104/0x120
[  836.229562]  __lock_acquire+0x15b8/0x2a10
[  836.230201]  lock_acquire+0xce/0x2d0
[  836.230776]  ? mlx5_lag_do_mirred+0x3b/0x70 [mlx5_core]
[  836.231614]  ? find_held_lock+0x2b/0x80
[  836.232221]  __mutex_lock+0x6b/0xf80
[  836.232799]  ? mlx5_lag_do_mirred+0x3b/0x70 [mlx5_core]
[  836.233636]  ? mlx5_lag_do_mirred+0x3b/0x70 [mlx5_core]
[  836.234451]  ? xa_load+0xc3/0x190
[  836.234995]  mlx5_lag_do_mirred+0x3b/0x70 [mlx5_core]
[  836.235803]  tc_act_parse_mirred+0x25b/0x800 [mlx5_core]
[  836.236636]  ? tc_act_can_offload_mirred+0x135/0x210 [mlx5_core]
[  836.237550]  parse_tc_actions+0x168/0x5a0 [mlx5_core]
[  836.238364]  __mlx5e_add_fdb_flow+0x263/0x480 [mlx5_core]
[  836.239202]  mlx5e_configure_flower+0x8a0/0x1820 [mlx5_core]
[  836.240076]  ? lock_acquire+0xce/0x2d0
[  836.240668]  ? tc_setup_cb_add+0x5b/0x200
[  836.241294]  tc_setup_cb_add+0xd7/0x200
[  836.241917]  fl_hw_replace_filter+0x14c/0x1f0 [cls_flower]
[  836.242709]  fl_change+0xbbe/0x1730 [cls_flower]
[  836.243408]  tc_new_tfilter+0x407/0xd90
[  836.244043]  ? tc_del_tfilter+0x880/0x880
[  836.244672]  rtnetlink_rcv_msg+0x406/0x5a0
[  836.245310]  ? netlink_deliver_tap+0x7a/0x4b0
[  836.245991]  ? if_nlmsg_stats_size+0x2b0/0x2b0
[  836.246675]  netlink_rcv_skb+0x4e/0xf0
[  836.258046]  netlink_unicast+0x190/0x250
[  836.258669]  netlink_sendmsg+0x243/0x4b0
[  836.259288]  sock_sendmsg+0x33/0x40
[  836.259857]  ____sys_sendmsg+0x1d1/0x1f0
[  836.260473]  ___sys_sendmsg+0xab/0xf0
[  836.261064]  ? lock_acquire+0xce/0x2d0
[  836.261669]  ? find_held_lock+0x2b/0x80
[  836.262272]  ? __fget_files+0xb9/0x190
[  836.262871]  ? __fget_files+0xd3/0x190
[  836.263462]  __sys_sendmsg+0x51/0x90
[  836.264064]  do_syscall_64+0x3d/0x90
[  836.264652]  entry_SYSCALL_64_after_hwframe+0x46/0xb0
[  836.265425] RIP: 0033:0x7fdbe5e2677d

[  836.266012] Code: 28 89 54 24 1c 48 89 74 24 10 89 7c 24 08 e8 ba ee
ff ff 8b 54 24 1c 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 2e 00 00 00 0f
05 <48> 3d 00 f0 ff ff 77 33 44 89 c7 48 89 44 24 08 e8 ee ee ff ff 48
[  836.268485] RSP: 002b:00007fdbe48a75a0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e
[  836.269598] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fdbe5e2677d
[  836.270576] RDX: 0000000000000000 RSI: 00007fdbe48a7640 RDI: 000000000000003c
[  836.271565] RBP: 00007fdbe48a8368 R08: 0000000000000000 R09: 0000000000000000
[  836.272546] R10: 00007fdbe48a84b0 R11: 0000000000000293 R12: 0000557bd17dc860
[  836.273527] R13: 0000000000000000 R14: 0000557bd17dc860 R15: 00007fdbe48a7640

[  836.274521]  </TASK>

To avoid using mode holding ldev->lock in the configure flow, we queue a
work to the lag workqueue and cease wait on a completion object.

In addition, we remove the lock from mlx5_lag_do_mirred() since it is
not really protecting anything.

It should be noted that an actual deadlock has not been observed.

Signed-off-by: Eli Cohen <[email protected]>
Reviewed-by: Mark Bloch <[email protected]>
Signed-off-by: Saeed Mahameed <[email protected]>
alistair23 pushed a commit that referenced this issue Dec 11, 2022
test_bpf tail call tests end up as:

  test_bpf: #0 Tail call leaf jited:1 85 PASS
  test_bpf: #1 Tail call 2 jited:1 111 PASS
  test_bpf: #2 Tail call 3 jited:1 145 PASS
  test_bpf: #3 Tail call 4 jited:1 170 PASS
  test_bpf: #4 Tail call load/store leaf jited:1 190 PASS
  test_bpf: #5 Tail call load/store jited:1
  BUG: Unable to handle kernel data access on write at 0xf1b4e000
  Faulting instruction address: 0xbe86b710
  Oops: Kernel access of bad area, sig: 11 [#1]
  BE PAGE_SIZE=4K MMU=Hash PowerMac
  Modules linked in: test_bpf(+)
  CPU: 0 PID: 97 Comm: insmod Not tainted 6.1.0-rc4+ torvalds#195
  Hardware name: PowerMac3,1 750CL 0x87210 PowerMac
  NIP:  be86b710 LR: be857e88 CTR: be86b704
  REGS: f1b4df20 TRAP: 0300   Not tainted  (6.1.0-rc4+)
  MSR:  00009032 <EE,ME,IR,DR,RI>  CR: 28008242  XER: 00000000
  DAR: f1b4e000 DSISR: 42000000
  GPR00: 00000001 f1b4dfe c11d2280 00000000 00000000 00000000 00000002 00000000
  GPR08: f1b4e000 be86b704 f1b4e000 00000000 00000000 100d816a f2440000 fe73baa8
  GPR16: f2458000 00000000 c1941ae4 f1fe2248 00000045 c0de0000 f2458030 00000000
  GPR24: 000003e8 0000000f f2458000 f1b4dc90 3e584b46 00000000 f24466a0 c1941a00
  NIP [be86b710] 0xbe86b710
  LR [be857e88] __run_one+0xec/0x264 [test_bpf]
  Call Trace:
  [f1b4dfe] [00000002] 0x2 (unreliable)
  Instruction dump:
  XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
  XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
  ---[ end trace 0000000000000000 ]---

This is a tentative to write above the stack. The problem is encoutered
with tests added by commit 38608ee ("bpf, tests: Add load store
test case for tail call")

This happens because tail call is done to a BPF prog with a different
stack_depth. At the time being, the stack is kept as is when the caller
tail calls its callee. But at exit, the callee restores the stack based
on its own properties. Therefore here, at each run, r1 is erroneously
increased by 32 - 16 = 16 bytes.

This was done that way in order to pass the tail call count from caller
to callee through the stack. As powerpc32 doesn't have a red zone in
the stack, it was necessary the maintain the stack as is for the tail
call. But it was not anticipated that the BPF frame size could be
different.

Let's take a new approach. Use register r4 to carry the tail call count
during the tail call, and save it into the stack at function entry if
required. This means the input parameter must be in r3, which is more
correct as it is a 32 bits parameter, then tail call better match with
normal BPF function entry, the down side being that we move that input
parameter back and forth between r3 and r4. That can be optimised later.

Doing that also has the advantage of maximising the common parts between
tail calls and a normal function exit.

With the fix, tail call tests are now successfull:

  test_bpf: #0 Tail call leaf jited:1 53 PASS
  test_bpf: #1 Tail call 2 jited:1 115 PASS
  test_bpf: #2 Tail call 3 jited:1 154 PASS
  test_bpf: #3 Tail call 4 jited:1 165 PASS
  test_bpf: #4 Tail call load/store leaf jited:1 101 PASS
  test_bpf: #5 Tail call load/store jited:1 141 PASS
  test_bpf: #6 Tail call error path, max count reached jited:1 994 PASS
  test_bpf: torvalds#7 Tail call count preserved across function calls jited:1 140975 PASS
  test_bpf: torvalds#8 Tail call error path, NULL target jited:1 110 PASS
  test_bpf: torvalds#9 Tail call error path, index out of range jited:1 69 PASS
  test_bpf: test_tail_calls: Summary: 10 PASSED, 0 FAILED, [10/10 JIT'ed]

Suggested-by: Naveen N. Rao <[email protected]>
Fixes: 51c66ad ("powerpc/bpf: Implement extended BPF on PPC32")
Cc: [email protected]
Signed-off-by: Christophe Leroy <[email protected]>
Tested-by: Naveen N. Rao <[email protected]
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/757acccb7fbfc78efa42dcf3c974b46678198905.1669278887.git.christophe.leroy@csgroup.eu
alistair23 pushed a commit that referenced this issue Dec 11, 2022
Matt reported a splat at msk close time:

    BUG: sleeping function called from invalid context at net/mptcp/protocol.c:2877
    in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 155, name: packetdrill
    preempt_count: 201, expected: 0
    RCU nest depth: 0, expected: 0
    4 locks held by packetdrill/155:
    #0: ffff888001536990 (&sb->s_type->i_mutex_key#6){+.+.}-{3:3}, at: __sock_release (net/socket.c:650)
    #1: ffff88800b498130 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close (net/mptcp/protocol.c:2973)
    #2: ffff88800b49a130 (sk_lock-AF_INET/1){+.+.}-{0:0}, at: __mptcp_close_ssk (net/mptcp/protocol.c:2363)
    #3: ffff88800b49a0b0 (slock-AF_INET){+...}-{2:2}, at: __lock_sock_fast (include/net/sock.h:1820)
    Preemption disabled at:
    0x0
    CPU: 1 PID: 155 Comm: packetdrill Not tainted 6.1.0-rc5 torvalds#365
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
    Call Trace:
    <TASK>
    dump_stack_lvl (lib/dump_stack.c:107 (discriminator 4))
    __might_resched.cold (kernel/sched/core.c:9891)
    __mptcp_destroy_sock (include/linux/kernel.h:110)
    __mptcp_close (net/mptcp/protocol.c:2959)
    mptcp_subflow_queue_clean (include/net/sock.h:1777)
    __mptcp_close_ssk (net/mptcp/protocol.c:2363)
    mptcp_destroy_common (net/mptcp/protocol.c:3170)
    mptcp_destroy (include/net/sock.h:1495)
    __mptcp_destroy_sock (net/mptcp/protocol.c:2886)
    __mptcp_close (net/mptcp/protocol.c:2959)
    mptcp_close (net/mptcp/protocol.c:2974)
    inet_release (net/ipv4/af_inet.c:432)
    __sock_release (net/socket.c:651)
    sock_close (net/socket.c:1367)
    __fput (fs/file_table.c:320)
    task_work_run (kernel/task_work.c:181 (discriminator 1))
    exit_to_user_mode_prepare (include/linux/resume_user_mode.h:49)
    syscall_exit_to_user_mode (kernel/entry/common.c:130)
    do_syscall_64 (arch/x86/entry/common.c:87)
    entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)

We can't call mptcp_close under the 'fast' socket lock variant, replace
it with a sock_lock_nested() as the relevant code is already under the
listening msk socket lock protection.

Reported-by: Matthieu Baerts <[email protected]>
Closes: multipath-tcp/mptcp_net-next#316
Fixes: 30e51b9 ("mptcp: fix unreleased socket in accept queue")
Signed-off-by: Paolo Abeni <[email protected]>
Reviewed-by: Matthieu Baerts <[email protected]>
Signed-off-by: Matthieu Baerts <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>
alistair23 pushed a commit that referenced this issue Dec 11, 2022
…kernel/git/at91/linux into arm/fixes

AT91 fixes for 6.1 #3

It contains:
- build fix for SAMA5D3 devices which don't have an L2 cache and due to this
  accesssing outer_cache.write_sec in sama5_secure_cache_init() could throw
  undefined reference to `outer_cache' if CONFIG_OUTER_CACHE is disabled
  from common sama5_defconfig.

* tag 'at91-fixes-6.1-3' of https://git.kernel.org/pub/scm/linux/kernel/git/at91/linux:
  ARM: at91: fix build for SAMA5D3 w/o L2 cache

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnd Bergmann <[email protected]>
alistair23 pushed a commit that referenced this issue Dec 11, 2022
QAT devices on Intel Sapphire Rapids and Emerald Rapids have a defect in
address translation service (ATS). These devices may inadvertently issue
ATS invalidation completion before posted writes initiated with
translated address that utilized translations matching the invalidation
address range, violating the invalidation completion ordering.

This patch adds an extra device TLB invalidation for the affected devices,
it is needed to ensure no more posted writes with translated address
following the invalidation completion. Therefore, the ordering is
preserved and data-corruption is prevented.

Device TLBs are invalidated under the following six conditions:
1. Device driver does DMA API unmap IOVA
2. Device driver unbind a PASID from a process, sva_unbind_device()
3. PASID is torn down, after PASID cache is flushed. e.g. process
exit_mmap() due to crash
4. Under SVA usage, called by mmu_notifier.invalidate_range() where
VM has to free pages that were unmapped
5. userspace driver unmaps a DMA buffer
6. Cache invalidation in vSVA usage (upcoming)

For #1 and #2, device drivers are responsible for stopping DMA traffic
before unmap/unbind. For #3, iommu driver gets mmu_notifier to
invalidate TLB the same way as normal user unmap which will do an extra
invalidation. The dTLB invalidation after PASID cache flush does not
need an extra invalidation.

Therefore, we only need to deal with #4 and #5 in this patch. #1 is also
covered by this patch due to common code path with #5.

Tested-by: Yuzhang Luo <[email protected]>
Reviewed-by: Ashok Raj <[email protected]>
Reviewed-by: Kevin Tian <[email protected]>
Signed-off-by: Jacob Pan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Lu Baolu <[email protected]>
Signed-off-by: Joerg Roedel <[email protected]>
alistair23 pushed a commit that referenced this issue Dec 11, 2022
When sending packets between nodes in netns, it calls tipc_lxc_xmit() for
peer node to receive the packets where tipc_sk_mcast_rcv()/tipc_sk_rcv()
might be called, and it's pretty much like in tipc_rcv().

Currently the local 'node rw lock' is held during calling tipc_lxc_xmit()
to protect the peer_net not being freed by another thread. However, when
receiving these packets, tipc_node_add_conn() might be called where the
peer 'node rw lock' is acquired. Then a dead lock warning is triggered by
lockdep detector, although it is not a real dead lock:

    WARNING: possible recursive locking detected
    --------------------------------------------
    conn_server/1086 is trying to acquire lock:
    ffff8880065cb020 (&n->lock#2){++--}-{2:2}, \
                     at: tipc_node_add_conn.cold.76+0xaa/0x211 [tipc]

    but task is already holding lock:
    ffff8880065cd020 (&n->lock#2){++--}-{2:2}, \
                     at: tipc_node_xmit+0x285/0xb30 [tipc]

    other info that might help us debug this:
     Possible unsafe locking scenario:

           CPU0
           ----
      lock(&n->lock#2);
      lock(&n->lock#2);

     *** DEADLOCK ***

     May be due to missing lock nesting notation

    4 locks held by conn_server/1086:
     #0: ffff8880036d1e40 (sk_lock-AF_TIPC){+.+.}-{0:0}, \
                          at: tipc_accept+0x9c0/0x10b0 [tipc]
     #1: ffff8880036d5f80 (sk_lock-AF_TIPC/1){+.+.}-{0:0}, \
                          at: tipc_accept+0x363/0x10b0 [tipc]
     #2: ffff8880065cd020 (&n->lock#2){++--}-{2:2}, \
                          at: tipc_node_xmit+0x285/0xb30 [tipc]
     #3: ffff888012e13370 (slock-AF_TIPC){+...}-{2:2}, \
                          at: tipc_sk_rcv+0x2da/0x1b40 [tipc]

    Call Trace:
     <TASK>
     dump_stack_lvl+0x44/0x5b
     __lock_acquire.cold.77+0x1f2/0x3d7
     lock_acquire+0x1d2/0x610
     _raw_write_lock_bh+0x38/0x80
     tipc_node_add_conn.cold.76+0xaa/0x211 [tipc]
     tipc_sk_finish_conn+0x21e/0x640 [tipc]
     tipc_sk_filter_rcv+0x147b/0x3030 [tipc]
     tipc_sk_rcv+0xbb4/0x1b40 [tipc]
     tipc_lxc_xmit+0x225/0x26b [tipc]
     tipc_node_xmit.cold.82+0x4a/0x102 [tipc]
     __tipc_sendstream+0x879/0xff0 [tipc]
     tipc_accept+0x966/0x10b0 [tipc]
     do_accept+0x37d/0x590

This patch avoids this warning by not holding the 'node rw lock' before
calling tipc_lxc_xmit(). As to protect the 'peer_net', rcu_read_lock()
should be enough, as in cleanup_net() when freeing the netns, it calls
synchronize_rcu() before the free is continued.

Also since tipc_lxc_xmit() is like the RX path in tipc_rcv(), it makes
sense to call it under rcu_read_lock(). Note that the right lock order
must be:

   rcu_read_lock();
   tipc_node_read_lock(n);
   tipc_node_read_unlock(n);
   tipc_lxc_xmit();
   rcu_read_unlock();

instead of:

   tipc_node_read_lock(n);
   rcu_read_lock();
   tipc_node_read_unlock(n);
   tipc_lxc_xmit();
   rcu_read_unlock();

and we have to call tipc_node_read_lock/unlock() twice in
tipc_node_xmit().

Fixes: f73b128 ("tipc: improve throughput between nodes in netns")
Reported-by: Shuang Li <[email protected]>
Signed-off-by: Xin Long <[email protected]>
Link: https://lore.kernel.org/r/5bdd1f8fee9db695cfff4528a48c9b9d0523fb00.1670110641.git.lucien.xin@gmail.com
Signed-off-by: Paolo Abeni <[email protected]>
alistair23 pushed a commit that referenced this issue Aug 15, 2023
Ido Schimmel says:

====================
nexthop: Nexthop dump fixes

Patches #1 and #3 fix two problems related to nexthops and nexthop
buckets dump, respectively. Patch #2 is a preparation for the third
patch.

The pattern described in these patches of splitting the NLMSG_DONE to a
separate response is prevalent in other rtnetlink dump callbacks. I
don't know if it's because I'm missing something or if this was done
intentionally to ensure the message is delivered to user space. After
commit 0642840 ("af_netlink: ensure that NLMSG_DONE never fails in
dumps") this is no longer necessary and I can improve these dump
callbacks assuming this analysis is correct.

No regressions in existing tests:

 # ./fib_nexthops.sh
 [...]
 Tests passed: 230
 Tests failed:   0
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
alistair23 pushed a commit that referenced this issue Jun 7, 2024
Andrii Nakryiko says:

====================
Fix BPF multi-uprobe PID filtering logic

It turns out that current implementation of multi-uprobe PID filtering logic
is broken. It filters by thread, while the promise is filtering by process.
Patch #1 fixes the logic trivially. The rest is testing and mitigations that
are necessary for libbpf to not break users of USDT programs.

v1->v2:
  - fix selftest in last patch (CI);
  - use semicolon in patch #3 (Jiri).
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
alistair23 pushed a commit that referenced this issue Jun 7, 2024
…git/netfilter/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

Patch #1 syzbot reports that nf_reinject() could be called without
         rcu_read_lock() when flushing pending packets at nfnetlink
         queue removal, from Eric Dumazet.

Patch #2 flushes ipset list:set when canceling garbage collection to
         reference to other lists to fix a race, from Jozsef Kadlecsik.

Patch #3 restores q-in-q matching with nft_payload by reverting
         f6ae9f1 ("netfilter: nft_payload: add C-VLAN support").

Patch #4 fixes vlan mangling in skbuff when vlan offload is present
         in skbuff, without this patch nft_payload corrupts packets
         in this case.

Patch #5 fixes possible nul-deref in tproxy no IP address is found in
         netdevice, reported by syzbot and patch from Florian Westphal.

Patch #6 removes a superfluous restriction which prevents loose fib
         lookups from input and forward hooks, from Eric Garver.

My assessment is that patches #1, #2 and #5 address possible kernel
crash, anything else in this batch fixes broken features.

netfilter pull request 24-05-29

* tag 'nf-24-05-29' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: nft_fib: allow from forward/input without iif selector
  netfilter: tproxy: bail out if IP has been disabled on the device
  netfilter: nft_payload: skbuff vlan metadata mangle support
  netfilter: nft_payload: restore vlan q-in-q match support
  netfilter: ipset: Add list flush to cancel_gc
  netfilter: nfnetlink_queue: acquire rcu_read_lock() in instance_destroy_rcu()
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>
alistair23 pushed a commit that referenced this issue Jun 14, 2024
With commit c4cb231 ("iommu/amd: Add support for enable/disable IOPF")
we are hitting below issue. This happens because in IOPF enablement path
it holds spin lock with irq disable and then tries to take mutex lock.

dmesg:
-----
[    0.938739] =============================
[    0.938740] [ BUG: Invalid wait context ]
[    0.938742] 6.10.0-rc1+ #1 Not tainted
[    0.938745] -----------------------------
[    0.938746] swapper/0/1 is trying to lock:
[    0.938748] ffffffff8c9f01d8 (&port_lock_key){....}-{3:3}, at: serial8250_console_write+0x78/0x4a0
[    0.938767] other info that might help us debug this:
[    0.938768] context-{5:5}
[    0.938769] 7 locks held by swapper/0/1:
[    0.938772]  #0: ffff888101a91310 (&group->mutex){+.+.}-{4:4}, at: bus_iommu_probe+0x70/0x160
[    0.938790]  #1: ffff888101d1f1b8 (&domain->lock){....}-{3:3}, at: amd_iommu_attach_device+0xa5/0x700
[    0.938799]  #2: ffff888101cc3d18 (&dev_data->lock){....}-{3:3}, at: amd_iommu_attach_device+0xc5/0x700
[    0.938806]  #3: ffff888100052830 (&iommu->lock){....}-{2:2}, at: amd_iommu_iopf_add_device+0x3f/0xa0
[    0.938813]  #4: ffffffff8945a340 (console_lock){+.+.}-{0:0}, at: _printk+0x48/0x50
[    0.938822]  #5: ffffffff8945a390 (console_srcu){....}-{0:0}, at: console_flush_all+0x58/0x4e0
[    0.938867]  #6: ffffffff82459f80 (console_owner){....}-{0:0}, at: console_flush_all+0x1f0/0x4e0
[    0.938872] stack backtrace:
[    0.938874] CPU: 2 PID: 1 Comm: swapper/0 Not tainted 6.10.0-rc1+ #1
[    0.938877] Hardware name: HP HP EliteBook 745 G3/807E, BIOS N73 Ver. 01.39 04/16/2019

Fix above issue by re-arranging code in attach device path:
  - move device PASID/IOPF enablement outside lock in AMD IOMMU driver.
    This is safe as core layer holds group->mutex lock before calling
    iommu_ops->attach_dev.

Reported-by: Borislav Petkov <[email protected]>
Reported-by: Mikhail Gavrilov <[email protected]>
Reported-by: Chris Bainbridge <[email protected]>
Fixes: c4cb231 ("iommu/amd: Add support for enable/disable IOPF")
Tested-by: Borislav Petkov <[email protected]>
Tested-by: Chris Bainbridge <[email protected]>
Tested-by: Mikhail Gavrilov <[email protected]>
Signed-off-by: Vasant Hegde <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Joerg Roedel <[email protected]>
alistair23 pushed a commit that referenced this issue Jun 14, 2024
…PLES event"

This reverts commit 7d1405c.

This causes segfaults in some cases, as reported by Milian:

  ```
  sudo /usr/bin/perf record -z --call-graph dwarf -e cycles -e
  raw_syscalls:sys_enter ls
  ...
  [ perf record: Woken up 3 times to write data ]
  malloc(): invalid next size (unsorted)
  Aborted
  ```

  Backtrace with GDB + debuginfod:

  ```
  malloc(): invalid next size (unsorted)

  Thread 1 "perf" received signal SIGABRT, Aborted.
  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6,
  no_tid=no_tid@entry=0) at pthread_kill.c:44
  Downloading source file /usr/src/debug/glibc/glibc/nptl/pthread_kill.c
  44            return INTERNAL_SYSCALL_ERROR_P (ret) ? INTERNAL_SYSCALL_ERRNO
  (ret) : 0;
  (gdb) bt
  #0  __pthread_kill_implementation (threadid=<optimized out>,
  signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44
  #1  0x00007ffff6ea8eb3 in __pthread_kill_internal (threadid=<optimized out>,
  signo=6) at pthread_kill.c:78
  #2  0x00007ffff6e50a30 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/
  raise.c:26
  #3  0x00007ffff6e384c3 in __GI_abort () at abort.c:79
  #4  0x00007ffff6e39354 in __libc_message_impl (fmt=fmt@entry=0x7ffff6fc22ea
  "%s\n") at ../sysdeps/posix/libc_fatal.c:132
  #5  0x00007ffff6eb3085 in malloc_printerr (str=str@entry=0x7ffff6fc5850
  "malloc(): invalid next size (unsorted)") at malloc.c:5772
  #6  0x00007ffff6eb657c in _int_malloc (av=av@entry=0x7ffff6ff6ac0
  <main_arena>, bytes=bytes@entry=368) at malloc.c:4081
  torvalds#7  0x00007ffff6eb877e in __libc_calloc (n=<optimized out>,
  elem_size=<optimized out>) at malloc.c:3754
  torvalds#8  0x000055555569bdb6 in perf_session.do_write_header ()
  torvalds#9  0x00005555555a373a in __cmd_record.constprop.0 ()
  torvalds#10 0x00005555555a6846 in cmd_record ()
  torvalds#11 0x000055555564db7f in run_builtin ()
  torvalds#12 0x000055555558ed77 in main ()
  ```

  Valgrind memcheck:
  ```
  ==45136== Invalid write of size 8
  ==45136==    at 0x2B38A5: perf_event__synthesize_id_sample (in /usr/bin/perf)
  ==45136==    by 0x157069: __cmd_record.constprop.0 (in /usr/bin/perf)
  ==45136==    by 0x15A845: cmd_record (in /usr/bin/perf)
  ==45136==    by 0x201B7E: run_builtin (in /usr/bin/perf)
  ==45136==    by 0x142D76: main (in /usr/bin/perf)
  ==45136==  Address 0x6a866a8 is 0 bytes after a block of size 40 alloc'd
  ==45136==    at 0x4849BF3: calloc (vg_replace_malloc.c:1675)
  ==45136==    by 0x3574AB: zalloc (in /usr/bin/perf)
  ==45136==    by 0x1570E0: __cmd_record.constprop.0 (in /usr/bin/perf)
  ==45136==    by 0x15A845: cmd_record (in /usr/bin/perf)
  ==45136==    by 0x201B7E: run_builtin (in /usr/bin/perf)
  ==45136==    by 0x142D76: main (in /usr/bin/perf)
  ==45136==
  ==45136== Syscall param write(buf) points to unaddressable byte(s)
  ==45136==    at 0x575953D: __libc_write (write.c:26)
  ==45136==    by 0x575953D: write (write.c:24)
  ==45136==    by 0x35761F: ion (in /usr/bin/perf)
  ==45136==    by 0x357778: writen (in /usr/bin/perf)
  ==45136==    by 0x1548F7: record__write (in /usr/bin/perf)
  ==45136==    by 0x15708A: __cmd_record.constprop.0 (in /usr/bin/perf)
  ==45136==    by 0x15A845: cmd_record (in /usr/bin/perf)
  ==45136==    by 0x201B7E: run_builtin (in /usr/bin/perf)
  ==45136==    by 0x142D76: main (in /usr/bin/perf)
  ==45136==  Address 0x6a866a8 is 0 bytes after a block of size 40 alloc'd
  ==45136==    at 0x4849BF3: calloc (vg_replace_malloc.c:1675)
  ==45136==    by 0x3574AB: zalloc (in /usr/bin/perf)
  ==45136==    by 0x1570E0: __cmd_record.constprop.0 (in /usr/bin/perf)
  ==45136==    by 0x15A845: cmd_record (in /usr/bin/perf)
  ==45136==    by 0x201B7E: run_builtin (in /usr/bin/perf)
  ==45136==    by 0x142D76: main (in /usr/bin/perf)
  ==45136==
 -----

Closes: https://lore.kernel.org/linux-perf-users/23879991.0LEYPuXRzz@milian-workstation/
Reported-by: Milian Wolff <[email protected]>
Tested-by: Milian Wolff <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected] # 6.8+
Link: https://lore.kernel.org/lkml/Zl9ksOlHJHnKM70p@x1
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
alistair23 pushed a commit that referenced this issue Jun 14, 2024
We have been seeing crashes on duplicate keys in
btrfs_set_item_key_safe():

  BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192)
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/ctree.c:2620!
  invalid opcode: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 #6
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
  RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs]

With the following stack trace:

  #0  btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4)
  #1  btrfs_drop_extents (fs/btrfs/file.c:411:4)
  #2  log_one_extent (fs/btrfs/tree-log.c:4732:9)
  #3  btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9)
  #4  btrfs_log_inode (fs/btrfs/tree-log.c:6626:9)
  #5  btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8)
  #6  btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8)
  torvalds#7  btrfs_sync_file (fs/btrfs/file.c:1933:8)
  torvalds#8  vfs_fsync_range (fs/sync.c:188:9)
  torvalds#9  vfs_fsync (fs/sync.c:202:9)
  torvalds#10 do_fsync (fs/sync.c:212:9)
  torvalds#11 __do_sys_fdatasync (fs/sync.c:225:9)
  torvalds#12 __se_sys_fdatasync (fs/sync.c:223:1)
  torvalds#13 __x64_sys_fdatasync (fs/sync.c:223:1)
  torvalds#14 do_syscall_x64 (arch/x86/entry/common.c:52:14)
  torvalds#15 do_syscall_64 (arch/x86/entry/common.c:83:7)
  torvalds#16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121)

So we're logging a changed extent from fsync, which is splitting an
extent in the log tree. But this split part already exists in the tree,
triggering the BUG().

This is the state of the log tree at the time of the crash, dumped with
drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py)
to get more details than btrfs_print_leaf() gives us:

  >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"])
  leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610
  leaf 33439744 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
          item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160
                  generation 7 transid 9 size 8192 nbytes 8473563889606862198
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 204 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417704.983333333 (2024-05-22 15:41:44)
                  mtime 1716417704.983333333 (2024-05-22 15:41:44)
                  otime 17592186044416.000000000 (559444-03-08 01:40:16)
          item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13
                  index 195 namelen 3 name: 193
          item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 4096 ram 12288
                  extent compression 0 (none)
          item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 4096 nr 8192
          item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096
  ...

So the real problem happened earlier: notice that items 4 (4k-12k) and 5
(8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and
item 5 starts at i_size.

Here is the state of the filesystem tree at the time of the crash:

  >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root
  >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0))
  >>> print_extent_buffer(nodes[0])
  leaf 30425088 level 0 items 184 generation 9 owner 5
  leaf 30425088 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
  	...
          item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160
                  generation 7 transid 7 size 4096 nbytes 12288
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 6 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417703.220000000 (2024-05-22 15:41:43)
                  mtime 1716417703.220000000 (2024-05-22 15:41:43)
                  otime 1716417703.220000000 (2024-05-22 15:41:43)
          item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13
                  index 195 namelen 3 name: 193
          item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 8192 ram 12288
                  extent compression 0 (none)
          item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096

Item 5 in the log tree corresponds to item 183 in the filesystem tree,
but nothing matches item 4. Furthermore, item 183 is the last item in
the leaf.

btrfs_log_prealloc_extents() is responsible for logging prealloc extents
beyond i_size. It first truncates any previously logged prealloc extents
that start beyond i_size. Then, it walks the filesystem tree and copies
the prealloc extent items to the log tree.

If it hits the end of a leaf, then it calls btrfs_next_leaf(), which
unlocks the tree and does another search. However, while the filesystem
tree is unlocked, an ordered extent completion may modify the tree. In
particular, it may insert an extent item that overlaps with an extent
item that was already copied to the log tree.

This may manifest in several ways depending on the exact scenario,
including an EEXIST error that is silently translated to a full sync,
overlapping items in the log tree, or this crash. This particular crash
is triggered by the following sequence of events:

- Initially, the file has i_size=4k, a regular extent from 0-4k, and a
  prealloc extent beyond i_size from 4k-12k. The prealloc extent item is
  the last item in its B-tree leaf.
- The file is fsync'd, which copies its inode item and both extent items
  to the log tree.
- An xattr is set on the file, which sets the
  BTRFS_INODE_COPY_EVERYTHING flag.
- The range 4k-8k in the file is written using direct I/O. i_size is
  extended to 8k, but the ordered extent is still in flight.
- The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this
  calls copy_inode_items_to_log(), which calls
  btrfs_log_prealloc_extents().
- btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the
  filesystem tree. Since it starts before i_size, it skips it. Since it
  is the last item in its B-tree leaf, it calls btrfs_next_leaf().
- btrfs_next_leaf() unlocks the path.
- The ordered extent completion runs, which converts the 4k-8k part of
  the prealloc extent to written and inserts the remaining prealloc part
  from 8k-12k.
- btrfs_next_leaf() does a search and finds the new prealloc extent
  8k-12k.
- btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into
  the log tree. Note that it overlaps with the 4k-12k prealloc extent
  that was copied to the log tree by the first fsync.
- fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k
  extent that was written.
- This tries to drop the range 4k-8k in the log tree, which requires
  adjusting the start of the 4k-12k prealloc extent in the log tree to
  8k.
- btrfs_set_item_key_safe() sees that there is already an extent
  starting at 8k in the log tree and calls BUG().

Fix this by detecting when we're about to insert an overlapping file
extent item in the log tree and truncating the part that would overlap.

CC: [email protected] # 6.1+
Reviewed-by: Filipe Manana <[email protected]>
Signed-off-by: Omar Sandoval <[email protected]>
Signed-off-by: David Sterba <[email protected]>
alistair23 pushed a commit that referenced this issue Jun 14, 2024
…git/netfilter/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

Patch #1 fixes insufficient sanitization of netlink attributes for the
	 inner expression which can trigger nul-pointer dereference,
	 from Davide Ornaghi.

Patch #2 address a report that there is a race condition between
         namespace cleanup and the garbage collection of the list:set
         type. This patch resolves this issue with other minor issues
	 as well, from Jozsef Kadlecsik.

Patch #3 ip6_route_me_harder() ignores flowlabel/dsfield when ip dscp
	 has been mangled, this unbreaks ip6 dscp set $v,
	 from Florian Westphal.

All of these patches address issues that are present in several releases.

* tag 'nf-24-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: Use flowlabel flow key when re-routing mangled packets
  netfilter: ipset: Fix race between namespace cleanup and gc in the list:set type
  netfilter: nft_inner: validate mandatory meta and payload
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
alistair23 pushed a commit that referenced this issue Jun 14, 2024
Nikolay Aleksandrov says:

====================
net: bridge: mst: fix suspicious rcu usage warning

This set fixes a suspicious RCU usage warning triggered by syzbot[1] in
the bridge's MST code. After I converted br_mst_set_state to RCU, I
forgot to update the vlan group dereference helper. Fix it by using
the proper helper, in order to do that we need to pass the vlan group
which is already obtained correctly by the callers for their respective
context. Patch 01 is a requirement for the fix in patch 02.

Note I did consider rcu_dereference_rtnl() but the churn is much bigger
and in every part of the bridge. We can do that as a cleanup in
net-next.

[1] https://syzkaller.appspot.com/bug?extid=9bbe2de1bc9d470eb5fe
 =============================
 WARNING: suspicious RCU usage
 6.10.0-rc2-syzkaller-00235-g8a92980606e3 #0 Not tainted
 -----------------------------
 net/bridge/br_private.h:1599 suspicious rcu_dereference_protected() usage!

 other info that might help us debug this:

 rcu_scheduler_active = 2, debug_locks = 1
 4 locks held by syz-executor.1/5374:
  #0: ffff888022d50b18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:144 [inline]
  #0: ffff888022d50b18 (&mm->mmap_lock){++++}-{3:3}, at: __mm_populate+0x1b0/0x460 mm/gup.c:2111
  #1: ffffc90000a18c00 ((&p->forward_delay_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x650 kernel/time/timer.c:1789
  #2: ffff88805fb2ccb8 (&br->lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
  #2: ffff88805fb2ccb8 (&br->lock){+.-.}-{2:2}, at: br_forward_delay_timer_expired+0x50/0x440 net/bridge/br_stp_timer.c:86
  #3: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
  #3: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
  #3: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: br_mst_set_state+0x171/0x7a0 net/bridge/br_mst.c:105

 stack backtrace:
 CPU: 1 PID: 5374 Comm: syz-executor.1 Not tainted 6.10.0-rc2-syzkaller-00235-g8a92980606e3 #0
 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
 Call Trace:
  <IRQ>
  __dump_stack lib/dump_stack.c:88 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
  lockdep_rcu_suspicious+0x221/0x340 kernel/locking/lockdep.c:6712
  nbp_vlan_group net/bridge/br_private.h:1599 [inline]
  br_mst_set_state+0x29e/0x7a0 net/bridge/br_mst.c:106
  br_set_state+0x28a/0x7b0 net/bridge/br_stp.c:47
  br_forward_delay_timer_expired+0x176/0x440 net/bridge/br_stp_timer.c:88
  call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792
  expire_timers kernel/time/timer.c:1843 [inline]
  __run_timers kernel/time/timer.c:2417 [inline]
  __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428
  run_timer_base kernel/time/timer.c:2437 [inline]
  run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447
  handle_softirqs+0x2c4/0x970 kernel/softirq.c:554
  __do_softirq kernel/softirq.c:588 [inline]
  invoke_softirq kernel/softirq.c:428 [inline]
  __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637
  irq_exit_rcu+0x9/0x30 kernel/softirq.c:649
  instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
  sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
  </IRQ>
  <TASK>
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
alistair23 pushed a commit that referenced this issue Jun 26, 2024
The syzbot fuzzer found that the interrupt-URB completion callback in
the cdc-wdm driver was taking too long, and the driver's immediate
resubmission of interrupt URBs with -EPROTO status combined with the
dummy-hcd emulation to cause a CPU lockup:

cdc_wdm 1-1:1.0: nonzero urb status received: -71
cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes
watchdog: BUG: soft lockup - CPU#0 stuck for 26s! [syz-executor782:6625]
CPU#0 Utilization every 4s during lockup:
	#1:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#2:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#3:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#4:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#5:  98% system,	  1% softirq,	  3% hardirq,	  0% idle
Modules linked in:
irq event stamp: 73096
hardirqs last  enabled at (73095): [<ffff80008037bc00>] console_emit_next_record kernel/printk/printk.c:2935 [inline]
hardirqs last  enabled at (73095): [<ffff80008037bc00>] console_flush_all+0x650/0xb74 kernel/printk/printk.c:2994
hardirqs last disabled at (73096): [<ffff80008af10b00>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline]
hardirqs last disabled at (73096): [<ffff80008af10b00>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551
softirqs last  enabled at (73048): [<ffff8000801ea530>] softirq_handle_end kernel/softirq.c:400 [inline]
softirqs last  enabled at (73048): [<ffff8000801ea530>] handle_softirqs+0xa60/0xc34 kernel/softirq.c:582
softirqs last disabled at (73043): [<ffff800080020de8>] __do_softirq+0x14/0x20 kernel/softirq.c:588
CPU: 0 PID: 6625 Comm: syz-executor782 Tainted: G        W          6.10.0-rc2-syzkaller-g8867bbd4a056 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024

Testing showed that the problem did not occur if the two error
messages -- the first two lines above -- were removed; apparently adding
material to the kernel log takes a surprisingly large amount of time.

In any case, the best approach for preventing these lockups and to
avoid spamming the log with thousands of error messages per second is
to ratelimit the two dev_err() calls.  Therefore we replace them with
dev_err_ratelimited().

Signed-off-by: Alan Stern <[email protected]>
Suggested-by: Greg KH <[email protected]>
Reported-and-tested-by: [email protected]
Closes: https://lore.kernel.org/linux-usb/[email protected]/
Reported-and-tested-by: [email protected]
Closes: https://lore.kernel.org/linux-usb/[email protected]/
Fixes: 9908a32 ("USB: remove err() macro from usb class drivers")
Link: https://lore.kernel.org/linux-usb/[email protected]/
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
alistair23 pushed a commit that referenced this issue Jun 26, 2024
…git/netfilter/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

Patch #1 fixes the suspicious RCU usage warning that resulted from the
	 recent fix for the race between namespace cleanup and gc in
	 ipset left out checking the pernet exit phase when calling
	 rcu_dereference_protected(), from Jozsef Kadlecsik.

Patch #2 fixes incorrect input and output netdevice in SRv6 prerouting
	 hooks, from Jianguo Wu.

Patch #3 moves nf_hooks_lwtunnel sysctl toggle to the netfilter core.
	 The connection tracking system is loaded on-demand, this
	 ensures availability of this knob regardless.

Patch #4-#5 adds selftests for SRv6 netfilter hooks also from Jianguo Wu.

netfilter pull request 24-06-19

* tag 'nf-24-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  selftests: add selftest for the SRv6 End.DX6 behavior with netfilter
  selftests: add selftest for the SRv6 End.DX4 behavior with netfilter
  netfilter: move the sysctl nf_hooks_lwtunnel into the netfilter core
  seg6: fix parameter passing when calling NF_HOOK() in End.DX4 and End.DX6 behaviors
  netfilter: ipset: Fix suspicious rcu_dereference_protected()
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>
alistair23 pushed a commit that referenced this issue Jul 2, 2024
…play

During inode logging (and log replay too), we are holding a transaction
handle and we often need to call btrfs_iget(), which will read an inode
from its subvolume btree if it's not loaded in memory and that results in
allocating an inode with GFP_KERNEL semantics at the btrfs_alloc_inode()
callback - and this may recurse into the filesystem in case we are under
memory pressure and attempt to commit the current transaction, resulting
in a deadlock since the logging (or log replay) task is holding a
transaction handle open.

Syzbot reported this with the following stack traces:

  WARNING: possible circular locking dependency detected
  6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0 Not tainted
  ------------------------------------------------------
  syz-executor.1/9919 is trying to acquire lock:
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:334 [inline]
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:3891 [inline]
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:3981 [inline]
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020

  but task is already holding lock:
  ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #3 (&ei->log_mutex){+.+.}-{3:3}:
         __mutex_lock_common kernel/locking/mutex.c:608 [inline]
         __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
         btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481
         btrfs_log_inode_parent+0x8cb/0x2a90 fs/btrfs/tree-log.c:7079
         btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
         btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
         vfs_fsync_range+0x141/0x230 fs/sync.c:188
         generic_write_sync include/linux/fs.h:2794 [inline]
         btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
         new_sync_write fs/read_write.c:497 [inline]
         vfs_write+0x6b6/0x1140 fs/read_write.c:590
         ksys_write+0x12f/0x260 fs/read_write.c:643
         do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
         __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
         do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
         entry_SYSENTER_compat_after_hwframe+0x84/0x8e

  -> #2 (btrfs_trans_num_extwriters){++++}-{0:0}:
         join_transaction+0x164/0xf40 fs/btrfs/transaction.c:315
         start_transaction+0x427/0x1a70 fs/btrfs/transaction.c:700
         btrfs_commit_super+0xa1/0x110 fs/btrfs/disk-io.c:4170
         close_ctree+0xcb0/0xf90 fs/btrfs/disk-io.c:4324
         generic_shutdown_super+0x159/0x3d0 fs/super.c:642
         kill_anon_super+0x3a/0x60 fs/super.c:1226
         btrfs_kill_super+0x3b/0x50 fs/btrfs/super.c:2096
         deactivate_locked_super+0xbe/0x1a0 fs/super.c:473
         deactivate_super+0xde/0x100 fs/super.c:506
         cleanup_mnt+0x222/0x450 fs/namespace.c:1267
         task_work_run+0x14e/0x250 kernel/task_work.c:180
         resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
         exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
         exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
         __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
         syscall_exit_to_user_mode+0x278/0x2a0 kernel/entry/common.c:218
         __do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389
         do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
         entry_SYSENTER_compat_after_hwframe+0x84/0x8e

  -> #1 (btrfs_trans_num_writers){++++}-{0:0}:
         __lock_release kernel/locking/lockdep.c:5468 [inline]
         lock_release+0x33e/0x6c0 kernel/locking/lockdep.c:5774
         percpu_up_read include/linux/percpu-rwsem.h:99 [inline]
         __sb_end_write include/linux/fs.h:1650 [inline]
         sb_end_intwrite include/linux/fs.h:1767 [inline]
         __btrfs_end_transaction+0x5ca/0x920 fs/btrfs/transaction.c:1071
         btrfs_commit_inode_delayed_inode+0x228/0x330 fs/btrfs/delayed-inode.c:1301
         btrfs_evict_inode+0x960/0xe80 fs/btrfs/inode.c:5291
         evict+0x2ed/0x6c0 fs/inode.c:667
         iput_final fs/inode.c:1741 [inline]
         iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
         iput+0x5c/0x80 fs/inode.c:1757
         dentry_unlink_inode+0x295/0x480 fs/dcache.c:400
         __dentry_kill+0x1d0/0x600 fs/dcache.c:603
         dput.part.0+0x4b1/0x9b0 fs/dcache.c:845
         dput+0x1f/0x30 fs/dcache.c:835
         ovl_stack_put+0x60/0x90 fs/overlayfs/util.c:132
         ovl_destroy_inode+0xc6/0x190 fs/overlayfs/super.c:182
         destroy_inode+0xc4/0x1b0 fs/inode.c:311
         iput_final fs/inode.c:1741 [inline]
         iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
         iput+0x5c/0x80 fs/inode.c:1757
         dentry_unlink_inode+0x295/0x480 fs/dcache.c:400
         __dentry_kill+0x1d0/0x600 fs/dcache.c:603
         shrink_kill fs/dcache.c:1048 [inline]
         shrink_dentry_list+0x140/0x5d0 fs/dcache.c:1075
         prune_dcache_sb+0xeb/0x150 fs/dcache.c:1156
         super_cache_scan+0x32a/0x550 fs/super.c:221
         do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435
         shrink_slab_memcg mm/shrinker.c:548 [inline]
         shrink_slab+0xa87/0x1310 mm/shrinker.c:626
         shrink_one+0x493/0x7c0 mm/vmscan.c:4790
         shrink_many mm/vmscan.c:4851 [inline]
         lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951
         shrink_node mm/vmscan.c:5910 [inline]
         kswapd_shrink_node mm/vmscan.c:6720 [inline]
         balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911
         kswapd+0x5ea/0xbf0 mm/vmscan.c:7180
         kthread+0x2c1/0x3a0 kernel/kthread.c:389
         ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
         ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

  -> #0 (fs_reclaim){+.+.}-{0:0}:
         check_prev_add kernel/locking/lockdep.c:3134 [inline]
         check_prevs_add kernel/locking/lockdep.c:3253 [inline]
         validate_chain kernel/locking/lockdep.c:3869 [inline]
         __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
         lock_acquire kernel/locking/lockdep.c:5754 [inline]
         lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
         __fs_reclaim_acquire mm/page_alloc.c:3801 [inline]
         fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815
         might_alloc include/linux/sched/mm.h:334 [inline]
         slab_pre_alloc_hook mm/slub.c:3891 [inline]
         slab_alloc_node mm/slub.c:3981 [inline]
         kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020
         btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411
         alloc_inode+0x5d/0x230 fs/inode.c:261
         iget5_locked fs/inode.c:1235 [inline]
         iget5_locked+0x1c9/0x2c0 fs/inode.c:1228
         btrfs_iget_locked fs/btrfs/inode.c:5590 [inline]
         btrfs_iget_path fs/btrfs/inode.c:5607 [inline]
         btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636
         add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline]
         copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928
         btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592
         log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline]
         btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718
         btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline]
         btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141
         btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
         btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
         vfs_fsync_range+0x141/0x230 fs/sync.c:188
         generic_write_sync include/linux/fs.h:2794 [inline]
         btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
         do_iter_readv_writev+0x504/0x780 fs/read_write.c:741
         vfs_writev+0x36f/0xde0 fs/read_write.c:971
         do_pwritev+0x1b2/0x260 fs/read_write.c:1072
         __do_compat_sys_pwritev2 fs/read_write.c:1218 [inline]
         __se_compat_sys_pwritev2 fs/read_write.c:1210 [inline]
         __ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210
         do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
         __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
         do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
         entry_SYSENTER_compat_after_hwframe+0x84/0x8e

  other info that might help us debug this:

  Chain exists of:
    fs_reclaim --> btrfs_trans_num_extwriters --> &ei->log_mutex

   Possible unsafe locking scenario:

         CPU0                    CPU1
         ----                    ----
    lock(&ei->log_mutex);
                                 lock(btrfs_trans_num_extwriters);
                                 lock(&ei->log_mutex);
    lock(fs_reclaim);

   *** DEADLOCK ***

  7 locks held by syz-executor.1/9919:
   #0: ffff88802be20420 (sb_writers#23){.+.+}-{0:0}, at: do_pwritev+0x1b2/0x260 fs/read_write.c:1072
   #1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: inode_lock include/linux/fs.h:791 [inline]
   #1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: btrfs_inode_lock+0xc8/0x110 fs/btrfs/inode.c:385
   #2: ffff888065c0f778 (&ei->i_mmap_lock){++++}-{3:3}, at: btrfs_inode_lock+0xee/0x110 fs/btrfs/inode.c:388
   #3: ffff88802be20610 (sb_internal#4){.+.+}-{0:0}, at: btrfs_sync_file+0x95b/0xe10 fs/btrfs/file.c:1952
   #4: ffff8880546323f0 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290
   #5: ffff888054632418 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290
   #6: ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481

  stack backtrace:
  CPU: 2 PID: 9919 Comm: syz-executor.1 Not tainted 6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
  Call Trace:
   <TASK>
   __dump_stack lib/dump_stack.c:88 [inline]
   dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
   check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187
   check_prev_add kernel/locking/lockdep.c:3134 [inline]
   check_prevs_add kernel/locking/lockdep.c:3253 [inline]
   validate_chain kernel/locking/lockdep.c:3869 [inline]
   __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
   lock_acquire kernel/locking/lockdep.c:5754 [inline]
   lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
   __fs_reclaim_acquire mm/page_alloc.c:3801 [inline]
   fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815
   might_alloc include/linux/sched/mm.h:334 [inline]
   slab_pre_alloc_hook mm/slub.c:3891 [inline]
   slab_alloc_node mm/slub.c:3981 [inline]
   kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020
   btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411
   alloc_inode+0x5d/0x230 fs/inode.c:261
   iget5_locked fs/inode.c:1235 [inline]
   iget5_locked+0x1c9/0x2c0 fs/inode.c:1228
   btrfs_iget_locked fs/btrfs/inode.c:5590 [inline]
   btrfs_iget_path fs/btrfs/inode.c:5607 [inline]
   btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636
   add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline]
   copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928
   btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592
   log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline]
   btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718
   btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline]
   btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141
   btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
   btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
   vfs_fsync_range+0x141/0x230 fs/sync.c:188
   generic_write_sync include/linux/fs.h:2794 [inline]
   btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
   do_iter_readv_writev+0x504/0x780 fs/read_write.c:741
   vfs_writev+0x36f/0xde0 fs/read_write.c:971
   do_pwritev+0x1b2/0x260 fs/read_write.c:1072
   __do_compat_sys_pwritev2 fs/read_write.c:1218 [inline]
   __se_compat_sys_pwritev2 fs/read_write.c:1210 [inline]
   __ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210
   do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
   __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
   do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
   entry_SYSENTER_compat_after_hwframe+0x84/0x8e
  RIP: 0023:0xf7334579
  Code: b8 01 10 06 03 (...)
  RSP: 002b:00000000f5f265ac EFLAGS: 00000292 ORIG_RAX: 000000000000017b
  RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000200002c0
  RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
  RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
  R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Fix this by ensuring we are under a NOFS scope whenever we call
btrfs_iget() during inode logging and log replay.

Reported-by: [email protected]
Link: https://lore.kernel.org/linux-btrfs/[email protected]/
Fixes: 712e36c ("btrfs: use GFP_KERNEL in btrfs_alloc_inode")
Reviewed-by: Johannes Thumshirn <[email protected]>
Reviewed-by: Josef Bacik <[email protected]>
Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
alistair23 pushed a commit that referenced this issue Jul 2, 2024
The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  #1 __crash_kexec at ffffffff8c1338fa
  #2 panic at ffffffff8c1d69b9
  #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  torvalds#7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  torvalds#8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  torvalds#9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
torvalds#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
torvalds#11 dio_complete at ffffffff8c2b9fa7
torvalds#12 do_blockdev_direct_IO at ffffffff8c2bc09f
torvalds#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
torvalds#14 generic_file_direct_write at ffffffff8c1dcf14
torvalds#15 __generic_file_write_iter at ffffffff8c1dd07b
torvalds#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
torvalds#17 aio_write at ffffffff8c2cc72e
torvalds#18 kmem_cache_alloc at ffffffff8c248dde
torvalds#19 do_io_submit at ffffffff8c2ccada
torvalds#20 do_syscall_64 at ffffffff8c004984
torvalds#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <[email protected]>
Reviewed-by: Joseph Qi <[email protected]>
Reviewed-by: Heming Zhao <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Gang He <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
alistair23 pushed a commit that referenced this issue Nov 7, 2024
Syzkaller reported a lockdep splat:

  ============================================
  WARNING: possible recursive locking detected
  6.11.0-rc6-syzkaller-00019-g67784a74e258 #0 Not tainted
  --------------------------------------------
  syz-executor364/5113 is trying to acquire lock:
  ffff8880449f1958 (k-slock-AF_INET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
  ffff8880449f1958 (k-slock-AF_INET){+.-.}-{2:2}, at: sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328

  but task is already holding lock:
  ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
  ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328

  other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(k-slock-AF_INET);
    lock(k-slock-AF_INET);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  7 locks held by syz-executor364/5113:
   #0: ffff8880449f0e18 (sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1607 [inline]
   #0: ffff8880449f0e18 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg+0x153/0x1b10 net/mptcp/protocol.c:1806
   #1: ffff88803fe39ad8 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1607 [inline]
   #1: ffff88803fe39ad8 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg_fastopen+0x11f/0x530 net/mptcp/protocol.c:1727
   #2: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
   #2: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
   #2: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x5f/0x1b80 net/ipv4/ip_output.c:470
   #3: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
   #3: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
   #3: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x45f/0x1390 net/ipv4/ip_output.c:228
   #4: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
   #4: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x33b/0x15b0 net/core/dev.c:6104
   #5: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
   #5: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
   #5: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: ip_local_deliver_finish+0x230/0x5f0 net/ipv4/ip_input.c:232
   #6: ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
   #6: ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328

  stack backtrace:
  CPU: 0 UID: 0 PID: 5113 Comm: syz-executor364 Not tainted 6.11.0-rc6-syzkaller-00019-g67784a74e258 #0
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
  Call Trace:
   <IRQ>
   __dump_stack lib/dump_stack.c:93 [inline]
   dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
   check_deadlock kernel/locking/lockdep.c:3061 [inline]
   validate_chain+0x15d3/0x5900 kernel/locking/lockdep.c:3855
   __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
   lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
   __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
   _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
   spin_lock include/linux/spinlock.h:351 [inline]
   sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328
   mptcp_sk_clone_init+0x32/0x13c0 net/mptcp/protocol.c:3279
   subflow_syn_recv_sock+0x931/0x1920 net/mptcp/subflow.c:874
   tcp_check_req+0xfe4/0x1a20 net/ipv4/tcp_minisocks.c:853
   tcp_v4_rcv+0x1c3e/0x37f0 net/ipv4/tcp_ipv4.c:2267
   ip_protocol_deliver_rcu+0x22e/0x440 net/ipv4/ip_input.c:205
   ip_local_deliver_finish+0x341/0x5f0 net/ipv4/ip_input.c:233
   NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
   NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
   __netif_receive_skb_one_core net/core/dev.c:5661 [inline]
   __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5775
   process_backlog+0x662/0x15b0 net/core/dev.c:6108
   __napi_poll+0xcb/0x490 net/core/dev.c:6772
   napi_poll net/core/dev.c:6841 [inline]
   net_rx_action+0x89b/0x1240 net/core/dev.c:6963
   handle_softirqs+0x2c4/0x970 kernel/softirq.c:554
   do_softirq+0x11b/0x1e0 kernel/softirq.c:455
   </IRQ>
   <TASK>
   __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382
   local_bh_enable include/linux/bottom_half.h:33 [inline]
   rcu_read_unlock_bh include/linux/rcupdate.h:908 [inline]
   __dev_queue_xmit+0x1763/0x3e90 net/core/dev.c:4450
   dev_queue_xmit include/linux/netdevice.h:3105 [inline]
   neigh_hh_output include/net/neighbour.h:526 [inline]
   neigh_output include/net/neighbour.h:540 [inline]
   ip_finish_output2+0xd41/0x1390 net/ipv4/ip_output.c:235
   ip_local_out net/ipv4/ip_output.c:129 [inline]
   __ip_queue_xmit+0x118c/0x1b80 net/ipv4/ip_output.c:535
   __tcp_transmit_skb+0x2544/0x3b30 net/ipv4/tcp_output.c:1466
   tcp_rcv_synsent_state_process net/ipv4/tcp_input.c:6542 [inline]
   tcp_rcv_state_process+0x2c32/0x4570 net/ipv4/tcp_input.c:6729
   tcp_v4_do_rcv+0x77d/0xc70 net/ipv4/tcp_ipv4.c:1934
   sk_backlog_rcv include/net/sock.h:1111 [inline]
   __release_sock+0x214/0x350 net/core/sock.c:3004
   release_sock+0x61/0x1f0 net/core/sock.c:3558
   mptcp_sendmsg_fastopen+0x1ad/0x530 net/mptcp/protocol.c:1733
   mptcp_sendmsg+0x1884/0x1b10 net/mptcp/protocol.c:1812
   sock_sendmsg_nosec net/socket.c:730 [inline]
   __sock_sendmsg+0x1a6/0x270 net/socket.c:745
   ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597
   ___sys_sendmsg net/socket.c:2651 [inline]
   __sys_sendmmsg+0x3b2/0x740 net/socket.c:2737
   __do_sys_sendmmsg net/socket.c:2766 [inline]
   __se_sys_sendmmsg net/socket.c:2763 [inline]
   __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2763
   do_syscall_x64 arch/x86/entry/common.c:52 [inline]
   do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
   entry_SYSCALL_64_after_hwframe+0x77/0x7f
  RIP: 0033:0x7f04fb13a6b9
  Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 01 1a 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
  RSP: 002b:00007ffd651f42d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
  RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f04fb13a6b9
  RDX: 0000000000000001 RSI: 0000000020000d00 RDI: 0000000000000004
  RBP: 00007ffd651f4310 R08: 0000000000000001 R09: 0000000000000001
  R10: 0000000020000080 R11: 0000000000000246 R12: 00000000000f4240
  R13: 00007f04fb187449 R14: 00007ffd651f42f4 R15: 00007ffd651f4300
   </TASK>

As noted by Cong Wang, the splat is false positive, but the code
path leading to the report is an unexpected one: a client is
attempting an MPC handshake towards the in-kernel listener created
by the in-kernel PM for a port based signal endpoint.

Such connection will be never accepted; many of them can make the
listener queue full and preventing the creation of MPJ subflow via
such listener - its intended role.

Explicitly detect this scenario at initial-syn time and drop the
incoming MPC request.

Fixes: 1729cf1 ("mptcp: create the listening socket for new port")
Cc: [email protected]
Reported-by: [email protected]
Closes: https://syzkaller.appspot.com/bug?extid=f4aacdfef2c6a6529c3e
Cc: Cong Wang <[email protected]>
Signed-off-by: Paolo Abeni <[email protected]>
Reviewed-by: Matthieu Baerts (NGI0) <[email protected]>
Reviewed-by: Mat Martineau <[email protected]>
Signed-off-by: Matthieu Baerts (NGI0) <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
alistair23 pushed a commit that referenced this issue Nov 7, 2024
…/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for 6.12, take #3

- Stop wasting space in the HYP idmap, as we are dangerously close
  to the 4kB limit, and this has already exploded in -next

- Fix another race in vgic_init()

- Fix a UBSAN error when faking the cache topology with MTE
  enabled
alistair23 pushed a commit that referenced this issue Nov 7, 2024
Hou Tao says:

====================
The patch set fixes several issues in bits iterator. Patch #1 fixes the
kmemleak problem of bits iterator. Patch #2~#3 fix the overflow problem
of nr_bits. Patch #4 fixes the potential stack corruption when bits
iterator is used on 32-bit host. Patch #5 adds more test cases for bits
iterator.

Please see the individual patches for more details. And comments are
always welcome.
---
v4:
 * patch #1: add ack from Yafang
 * patch #3: revert code-churn like changes:
   (1) compute nr_bytes and nr_bits before the check of nr_words.
   (2) use nr_bits == 64 to check for single u64, preventing build
       warning on 32-bit hosts.
 * patch #4: use "BITS_PER_LONG == 32" instead of "!defined(CONFIG_64BIT)"

v3: https://lore.kernel.org/bpf/[email protected]/T/#t
  * split the bits-iterator related patches from "Misc fixes for bpf"
    patch set
  * patch #1: use "!nr_bits || bits >= nr_bits" to stop the iteration
  * patch #2: add a new helper for the overflow problem
  * patch #3: decrease the limitation from 512 to 511 and check whether
    nr_bytes is too large for bpf memory allocator explicitly
  * patch #5: add two more test cases for bit iterator

v2: http://lore.kernel.org/bpf/[email protected]
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
alistair23 pushed a commit that referenced this issue Nov 7, 2024
Petr Machata says:

====================
mlxsw: Fixes

In this patchset:

- Tx header should be pushed for each packet which is transmitted via
  Spectrum ASICs. Patch #1 adds a missing call to skb_cow_head() to make
  sure that there is both enough room to push the Tx header and that the
  SKB header is not cloned and can be modified.

- Commit b5b60bb ("mlxsw: pci: Use page pool for Rx buffers
  allocation") converted mlxsw to use page pool for Rx buffers allocation.
  Sync for CPU and for device should be done for Rx pages. In patches #2
  and #3, add the missing calls to sync pages for, respectively, CPU and
  the device.

- Patch #4 then fixes a bug to IPv6 GRE forwarding offload. Patch #5 adds
  a generic forwarding test that fails with mlxsw ports prior to the fix.
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
Projects
None yet
Development

No branches or pull requests

2 participants