UPSTREAM: media: usb: siano: Fix warning due to null work_func_t function pointer

[ Upstream commit 6f489a966fbeb0da63d45c2c66a8957eab604bf6 ]

The previous commit ebad8e731c1c ("media: usb: siano: Fix use after
free bugs caused by do_submit_urb") adds cancel_work_sync() in
smsusb_stop_streaming(). But smsusb_stop_streaming() may be called,
even if the work_struct surb->wq has not been initialized. As a result,
the warning will occur. One of the processes that could lead to warning
is shown below:

smsusb_probe()
  smsusb_init_device()
    if (!dev->in_ep || !dev->out_ep || align < 0) {
         smsusb_term_device(intf);
           smsusb_stop_streaming()
             cancel_work_sync(&dev->surbs[i].wq);
               __cancel_work_timer()
                 __flush_work()
                   if (WARN_ON(!work->func)) // work->func is null

The log reported by syzbot is shown below:

WARNING: CPU: 0 PID: 897 at kernel/workqueue.c:3066 __flush_work+0x798/0xa80 kernel/workqueue.c:3063
Modules linked in:
CPU: 0 PID: 897 Comm: kworker/0:2 Not tainted 6.2.0-rc1-syzkaller #0
RIP: 0010:__flush_work+0x798/0xa80 kernel/workqueue.c:3066
...
RSP: 0018:ffffc9000464ebf8 EFLAGS: 00010246
RAX: 1ffff11002dbb420 RBX: 0000000000000021 RCX: 1ffffffff204fa4e
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff888016dda0e8
RBP: ffffc9000464ed98 R08: 0000000000000001 R09: ffffffff90253b2f
R10: 0000000000000001 R11: 0000000000000000 R12: ffff888016dda0e8
R13: ffff888016dda0e8 R14: ffff888016dda100 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd4331efe8 CR3: 000000000b48e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __cancel_work_timer+0x315/0x460 kernel/workqueue.c:3160
 smsusb_stop_streaming drivers/media/usb/siano/smsusb.c:182 [inline]
 smsusb_term_device+0xda/0x2d0 drivers/media/usb/siano/smsusb.c:344
 smsusb_init_device+0x400/0x9ce drivers/media/usb/siano/smsusb.c:419
 smsusb_probe+0xbbd/0xc55 drivers/media/usb/siano/smsusb.c:567
...

This patch adds check before cancel_work_sync(). If surb->wq has not
been initialized, the cancel_work_sync() will not be executed.

Bug: 295075980
Reported-by: syzbot+27b0b464864741b18b99@syzkaller.appspotmail.com
Fixes: ebad8e731c1c ("media: usb: siano: Fix use after free bugs caused by do_submit_urb")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit 8abb53c5167cfb5bb275512a3da4ec2468478626)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: Ie2946408cfde466d0138c23093ec6738b7e51161
1 file changed
tree: 7484d171808bb8bb42e5b8aa3d073933d9f3b127
  1. android/
  2. arch/
  3. block/
  4. certs/
  5. crypto/
  6. Documentation/
  7. drivers/
  8. fs/
  9. include/
  10. init/
  11. ipc/
  12. kernel/
  13. lib/
  14. LICENSES/
  15. mm/
  16. net/
  17. samples/
  18. scripts/
  19. security/
  20. sound/
  21. tools/
  22. usr/
  23. virt/
  24. .clang-format
  25. .cocciconfig
  26. .get_maintainer.ignore
  27. .gitattributes
  28. .gitignore
  29. .mailmap
  30. build.config.aarch64
  31. build.config.allmodconfig
  32. build.config.allmodconfig.aarch64
  33. build.config.allmodconfig.arm
  34. build.config.allmodconfig.x86_64
  35. build.config.arm
  36. build.config.common
  37. build.config.db845c
  38. build.config.gki
  39. build.config.gki-debug.aarch64
  40. build.config.gki-debug.x86_64
  41. build.config.gki.aarch64
  42. build.config.gki.x86_64
  43. build.config.gki_kasan
  44. build.config.gki_kasan.aarch64
  45. build.config.gki_kasan.x86_64
  46. build.config.gki_kprobes
  47. build.config.gki_kprobes.aarch64
  48. build.config.gki_kprobes.x86_64
  49. build.config.hikey960
  50. build.config.x86_64
  51. COPYING
  52. CREDITS
  53. Kbuild
  54. Kconfig
  55. MAINTAINERS
  56. Makefile
  57. OWNERS
  58. README
  59. README.md
README.md

How do I submit patches to Android Common Kernels

  1. BEST: Make all of your changes to upstream Linux. If appropriate, backport to the stable releases. These patches will be merged automatically in the corresponding common kernels. If the patch is already in upstream Linux, post a backport of the patch that conforms to the patch requirements below.

  2. LESS GOOD: Develop your patches out-of-tree (from an upstream Linux point-of-view). Unless these are fixing an Android-specific bug, these are very unlikely to be accepted unless they have been coordinated with kernel-team@android.com. If you want to proceed, post a patch that conforms to the patch requirements below.

Common Kernel patch requirements

  • All patches must conform to the Linux kernel coding standards and pass script/checkpatch.pl
  • Patches shall not break gki_defconfig or allmodconfig builds for arm, arm64, x86, x86_64 architectures (see https://source.android.com/setup/build/building-kernels)
  • If the patch is not merged from an upstream branch, the subject must be tagged with the type of patch: UPSTREAM:, BACKPORT:, FROMGIT:, FROMLIST:, or ANDROID:.
  • All patches must have a Change-Id: tag (see https://gerrit-review.googlesource.com/Documentation/user-changeid.html)
  • If an Android bug has been assigned, there must be a Bug: tag.
  • All patches must have a Signed-off-by: tag by the author and the submitter

Additional requirements are listed below based on patch type

Requirements for backports from mainline Linux: UPSTREAM:, BACKPORT:

  • If the patch is a cherry-pick from Linux mainline with no changes at all
    • tag the patch subject with UPSTREAM:.
    • add upstream commit information with a (cherry-picked from ...) line
    • Example:
      • if the upstream commit message is
        important patch from upstream

        This is the detailed description of the important patch

        Signed-off-by: Fred Jones <fred.jones@foo.org>
    - then Joe Smith would upload the patch for the common kernel as
        UPSTREAM: important patch from upstream

        This is the detailed description of the important patch

        Signed-off-by: Fred Jones <fred.jones@foo.org>

        Bug: 135791357
        Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
        (cherry-picked from c31e73121f4c1ec41143423ac6ce3ce6dafdcec1)
        Signed-off-by: Joe Smith <joe.smith@foo.org>
  • If the patch requires any changes from the upstream version, tag the patch with BACKPORT: instead of UPSTREAM:.
    • use the same tags as UPSTREAM:
    • add comments about the changes under the (cherry-picked from ...) line
    • Example:
        BACKPORT: important patch from upstream

        This is the detailed description of the important patch

        Signed-off-by: Fred Jones <fred.jones@foo.org>

        Bug: 135791357
        Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
        (cherry-picked from c31e73121f4c1ec41143423ac6ce3ce6dafdcec1)
        [ Resolved minor conflict in drivers/foo/bar.c ]
        Signed-off-by: Joe Smith <joe.smith@foo.org>

Requirements for other backports: FROMGIT:, FROMLIST:,

  • If the patch has been merged into an upstream maintainer tree, but has not yet been merged into Linux mainline
    • tag the patch subject with FROMGIT:
    • add info on where the patch came from as (cherry picked from commit <sha1> <repo> <branch>). This must be a stable maintainer branch (not rebased, so don't use linux-next for example).
    • if changes were required, use BACKPORT: FROMGIT:
    • Example:
      • if the commit message in the maintainer tree is
        important patch from upstream

        This is the detailed description of the important patch

        Signed-off-by: Fred Jones <fred.jones@foo.org>
    - then Joe Smith would upload the patch for the common kernel as
        FROMGIT: important patch from upstream

        This is the detailed description of the important patch

        Signed-off-by: Fred Jones <fred.jones@foo.org>

        Bug: 135791357
        (cherry picked from commit 878a2fd9de10b03d11d2f622250285c7e63deace
         https://git.kernel.org/pub/scm/linux/kernel/git/foo/bar.git test-branch)
        Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
        Signed-off-by: Joe Smith <joe.smith@foo.org>
  • If the patch has been submitted to LKML, but not accepted into any maintainer tree
    • tag the patch subject with FROMLIST:
    • add a Link: tag with a link to the submittal on lore.kernel.org
    • if changes were required, use BACKPORT: FROMLIST:
    • Example:
        FROMLIST: important patch from upstream

        This is the detailed description of the important patch

        Signed-off-by: Fred Jones <fred.jones@foo.org>

        Bug: 135791357
        Link: https://lore.kernel.org/lkml/20190619171517.GA17557@someone.com/
        Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
        Signed-off-by: Joe Smith <joe.smith@foo.org>

Requirements for Android-specific patches: ANDROID:

  • If the patch is fixing a bug to Android-specific code
    • tag the patch subject with ANDROID:
    • add a Fixes: tag that cites the patch with the bug
    • Example:
        ANDROID: fix android-specific bug in foobar.c

        This is the detailed description of the important fix

        Fixes: 1234abcd2468 ("foobar: add cool feature")
        Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
        Signed-off-by: Joe Smith <joe.smith@foo.org>
  • If the patch is a new feature
    • tag the patch subject with ANDROID:
    • add a Bug: tag with the Android bug (required for android-specific features)