group.of.nepali.translators team mailing list archive

[Po-Hsu Lin <po-hsu.lin@xxxxxxxxxxxxx>]

** Changed in: ubuntu-kernel-tests
       Status: New => Fix Released

** Changed in: linux (Ubuntu)
       Status: Confirmed => Fix Released

-- 
You received this bug notification because you are a member of नेपाली
भाषा समायोजकहरुको समूह, which is subscribed to Xenial.
Matching subscriptions: Ubuntu 16.04 Bugs
https://bugs.launchpad.net/bugs/1822579

Title:
  Remove btrfs module after a failed fallocate attempt will cause error
  on 4.4 i386

Status in ubuntu-kernel-tests:
  Fix Released
Status in linux package in Ubuntu:
  Fix Released
Status in linux source package in Xenial:
  Fix Released

Bug description:
  SRU Justification:

  [Impact]

   * If fallocate() is failing on a btrfs subvolume when its qgroup
  quota limit exceeded, a previously allocated extent map isn't
  correctly released, causing a memory leak from the pool
  btrfs_extent_map.

   * Fix by correctly deallocating the object in case of failure

  [Test Case]
   
   * https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1822579/+attachment/5252459/+files/btrfs-fallocate-test.sh

  [Fix]

   *
  https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=be2d253cc98244765323a7c94cc1ac5cd5a17072

  Fix the memory leak by adding the proper free_extent_map() call to the
  failure path.

  [Regression Potential]

   * This is an upstream fix, tested on the affected platform. The patch
  is really small, backport changes are minimal. All the other Ubuntu
  releases are including this fix already.

  [Original bug report]
  If one issues a rmmod (or modprobe -r) command after a failed fallocate attempt, it will cause error with call trace:

   =============================================================================
   BUG btrfs_extent_map (Not tainted): Objects remaining in btrfs_extent_map on kmem_cache_close()
   -----------------------------------------------------------------------------

   Disabling lock debugging due to kernel taint
   INFO: Slab 0xf7526fb0 objects=34 used=1 fp=0xf43fef78 flags=0x2800080
   CPU: 1 PID: 1608 Comm: rmmod Tainted: G    B           4.4.0-143-generic #169-Ubuntu
   Hardware name: Dell Inc. PowerEdge R310/05XKKK, BIOS 1.11.0 09/18/2012
    c1b0d967 35a7d73c 00000286 f4ed9ddc c13c034f f7526fb0 f4ed9dfc f4ed9e70
    c11ccc42 c1a164b0 f7526fb0 00000022 00000001 f43fef78 02800080 656a624f
    20737463 616d6572 6e696e69 6e692067 72746220 655f7366 6e657478 616d5f74
   Call Trace:
    [<c13c034f>] dump_stack+0x58/0x79
    [<c11ccc42>] slab_err+0x82/0xa0
    [<c11d090d>] ? __kmalloc+0x22d/0x240
    [<c11ce550>] ? __free_slab+0xa0/0x130
    [<c11d0ba9>] ? free_partial+0xa9/0x1b0
    [<c11d0ba9>] ? free_partial+0xa9/0x1b0
    [<c11d0bce>] free_partial+0xce/0x1b0
    [<c11cf350>] ? __flush_cpu_slab+0x40/0x40
    [<c11d24e2>] __kmem_cache_shutdown+0x42/0x80
    [<c119e5e2>] kmem_cache_destroy+0x162/0x1e0
    [<f8dc0ac6>] extent_map_exit+0x16/0x20 [btrfs]
    [<f8e2ee20>] exit_btrfs_fs+0x26/0x206 [btrfs]
    [<c10fd19f>] SyS_delete_module+0x1af/0x200
    [<c11edbad>] ? ____fput+0xd/0x10
    [<c109062f>] ? task_work_run+0x8f/0xa0
    [<c10031f6>] ? exit_to_usermode_loop+0xb6/0xe0
    [<c10038af>] do_fast_syscall_32+0x9f/0x160
    [<c17e63f0>] sysenter_past_esp+0x3d/0x61
   INFO: Object 0xf43fe078 @offset=120
   kmem_cache_destroy btrfs_extent_map: Slab cache still has objects
   CPU: 1 PID: 1608 Comm: rmmod Tainted: G    B           4.4.0-143-generic #169-Ubuntu
   Hardware name: Dell Inc. PowerEdge R310/05XKKK, BIOS 1.11.0 09/18/2012
    c1b0d967 35a7d73c 00000286 f4ed9ed4 c13c034f ef34f600 ef34f674 f4ed9f0c
    c119e630 c1a14d18 f55f3220 f4ed9f04 000d96ab f4ed9eec f4ed9eec f4ed9ef4
    f4ed9ef4 35a7d73c 022ffd44 f8e46880 f4ed8000 f4ed9f14 f8dc0ac6 f4ed9f1c
   Call Trace:
    [<c13c034f>] dump_stack+0x58/0x79
    [<c119e630>] kmem_cache_destroy+0x1b0/0x1e0
    [<f8dc0ac6>] extent_map_exit+0x16/0x20 [btrfs]
    [<f8e2ee20>] exit_btrfs_fs+0x26/0x206 [btrfs]
    [<c10fd19f>] SyS_delete_module+0x1af/0x200
    [<c11edbad>] ? ____fput+0xd/0x10
    [<c109062f>] ? task_work_run+0x8f/0xa0
    [<c10031f6>] ? exit_to_usermode_loop+0xb6/0xe0
    [<c10038af>] do_fast_syscall_32+0x9f/0x160
    [<c17e63f0>] sysenter_past_esp+0x3d/0x61

  Steps to reproduce this:

  TMP=/tmp
  MNT=/tmp/mnt
  mkdir $MNT

  TMPIMG0=$TMP/test0.img
  DEV0=`losetup -f`

  truncate --size 512M $TMPIMG0
  losetup $DEV0 $TMPIMG0

  mkfs.btrfs -f $DEV0 >& /dev/null
  mount $DEV0 $MNT

  btrfs quota enable $MNT
  btrfs sub create $MNT/subv
  btrfs qgroup limit 10M $MNT/subv

  fallocate --length 20M $MNT/subv/data
  rmmod btrfs

  ProblemType: Bug
  DistroRelease: Ubuntu 16.04
  Package: linux-image-4.4.0-143-generic 4.4.0-143.169
  ProcVersionSignature: User Name 4.4.0-143.169-generic 4.4.170
  Uname: Linux 4.4.0-143-generic i686
  AlsaDevices:
   total 0
   crw-rw---- 1 root audio 116,  1 Apr  1 11:43 seq
   crw-rw---- 1 root audio 116, 33 Apr  1 11:43 timer
  AplayDevices: Error: [Errno 2] No such file or directory: 'aplay'
  ApportVersion: 2.20.1-0ubuntu2.18
  Architecture: i386
  ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord'
  AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1:
  Date: Mon Apr  1 11:55:56 2019
  IwConfig: Error: [Errno 2] No such file or directory: 'iwconfig'
  MachineType: Dell Inc. PowerEdge R310
  PciMultimedia:

  ProcFB:

  ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-143-generic root=UUID=6aaa11f6-d386-4c0c-b4b8-38e6c408980a ro
  RelatedPackageVersions:
   linux-restricted-modules-4.4.0-143-generic N/A
   linux-backports-modules-4.4.0-143-generic  N/A
   linux-firmware                             1.157.21
  RfKill: Error: [Errno 2] No such file or directory: 'rfkill'
  SourcePackage: linux
  UpgradeStatus: No upgrade log present (probably fresh install)
  dmi.bios.date: 09/18/2012
  dmi.bios.vendor: Dell Inc.
  dmi.bios.version: 1.11.0
  dmi.board.name: 05XKKK
  dmi.board.vendor: Dell Inc.
  dmi.board.version: A05
  dmi.chassis.type: 23
  dmi.chassis.vendor: Dell Inc.
  dmi.modalias: dmi:bvnDellInc.:bvr1.11.0:bd09/18/2012:svnDellInc.:pnPowerEdgeR310:pvr:rvnDellInc.:rn05XKKK:rvrA05:cvnDellInc.:ct23:cvr:
  dmi.product.name: PowerEdge R310
  dmi.sys.vendor: Dell Inc.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu-kernel-tests/+bug/1822579/+subscriptions