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android/kernel/common/refs/tags/android12-5.10-2021-11_r13
tag
687d81933c08ce8b0059b44cca9eda8609947eb5
tagger
Howard Chen <howardsoc@google.com>
Thu Apr 28 10:41:27 2022 +0800
object
817f661dfd9a38252a484755119891026ecd1464
android12-5.10 November 2021 release 13

Artifacts
  kernel: https://ci.android.com/builds/submitted/8503259/kernel_aarch64/latest
  boot.img: https://ci.android.com/builds/submitted/8506189/gsi_arm64-user/latest
commit
817f661dfd9a38252a484755119891026ecd1464
[log] [tgz]
author
Udipto Goswami <quic_ugoswami@quicinc.com>
Thu Jan 27 09:39:55 2022 +0530
committer
Todd Kjos <tkjos@google.com>
Mon Apr 25 17:30:05 2022 -0700
tree
ae5a39d34a79b2d0bdb7712460c496d308a9fc54
parent
17834ccbf30500d75524b23e6a79139d6c7b1a6c [diff]
FROMGIT: usb: f_fs: Fix use-after-free for epfile

Consider a case where ffs_func_eps_disable is called from
ffs_func_disable as part of composition switch and at the
same time ffs_epfile_release get called from userspace.
ffs_epfile_release will free up the read buffer and call
ffs_data_closed which in turn destroys ffs->epfiles and
mark it as NULL. While this was happening the driver has
already initialized the local epfile in ffs_func_eps_disable
which is now freed and waiting to acquire the spinlock. Once
spinlock is acquired the driver proceeds with the stale value
of epfile and tries to free the already freed read buffer
causing use-after-free.

Following is the illustration of the race:

      CPU1                                  CPU2

   ffs_func_eps_disable
   epfiles (local copy)
					ffs_epfile_release
					ffs_data_closed
					if (last file closed)
					ffs_data_reset
					ffs_data_clear
					ffs_epfiles_destroy
spin_lock
dereference epfiles

Fix this races by taking epfiles local copy & assigning it under
spinlock and if epfiles(local) is null then update it in ffs->epfiles
then finally destroy it.
Extending the scope further from the race, protecting the ep related
structures, and concurrent accesses.

Fixes: a9e6f83c2df (usb: gadget: f_fs: stop sleeping in ffs_func_eps_disable)
Reviewed-by: John Keeping <john@metanate.com>
Signed-off-by: Pratham Pratap <quic_ppratap@quicinc.com>
Co-developed-by: Udipto Goswami <quic_ugoswami@quicinc.com>
Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com>
Link: https://lore.kernel.org/r/1643256595-10797-1-git-send-email-quic_ugoswami@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

(cherry picked from commit ebe2b1add1055b903e2acd86b290a85297edc0b3
https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-linus)

BUG: 217829161
Change-Id: Iab64af51aece85df3208afd7b6cd108b955eae45
Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com>
1 file changed
tree: ae5a39d34a79b2d0bdb7712460c496d308a9fc54
  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.amlogic
  36. build.config.arm
  37. build.config.common
  38. build.config.db845c
  39. build.config.gki
  40. build.config.gki-debug.aarch64
  41. build.config.gki-debug.x86_64
  42. build.config.gki.aarch64
  43. build.config.gki.aarch64.fips140
  44. build.config.gki.x86_64
  45. build.config.gki_kasan
  46. build.config.gki_kasan.aarch64
  47. build.config.gki_kasan.x86_64
  48. build.config.gki_kprobes
  49. build.config.gki_kprobes.aarch64
  50. build.config.gki_kprobes.x86_64
  51. build.config.hikey960
  52. build.config.khwasan
  53. build.config.rockchip
  54. build.config.x86_64
  55. COPYING
  56. CREDITS
  57. Kbuild
  58. Kconfig
  59. MAINTAINERS
  60. Makefile
  61. OWNERS
  62. README
  63. 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.

    • Do not send patches upstream that contain only symbol exports. To be considered for upstream Linux, additions of EXPORT_SYMBOL_GPL() require an in-tree modular driver that uses the symbol -- so include the new driver or changes to an existing driver in the same patchset as the export.
    • When sending patches upstream, the commit message must contain a clear case for why the patch is needed and beneficial to the community. Enabling out-of-tree drivers or functionality is not not a persuasive case.

  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 commit ...) 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 commit 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 commit ...) 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 commit c31e73121f4c1ec41143423ac6ce3ce6dafdcec1)
        [joe: 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
    • add a Bug: tag with the Android bug (required for patches not accepted into a maintainer tree)
    • 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)