syzbot


possible deadlock in ocfs2_fiemap

Status: upstream: reported C repro on 2024/09/03 20:43
Subsystems: ocfs2
[Documentation on labels]
Reported-by: syzbot+ca440b457d21568f8021@syzkaller.appspotmail.com
First crash: 291d, last: 4h13m
Cause bisection: introduced by (bisect log) :
commit a3c06ae158dd6fa8336157c31d9234689d068d02
Author: Parav Pandit <parav@nvidia.com>
Date: Tue Jan 5 10:32:03 2021 +0000

  vdpa_sim_net: Add support for user supported devices

Crash: possible deadlock in ocfs2_fiemap (log)
Repro: C syz .config
  
Discussions (3)
Title Replies (including bot) Last reply
[PATCH] ocfs2: Fix possible deadlock in ocfs2_fiemap 1 (1) 2024/10/17 08:55
[syzbot] [ocfs2?] possible deadlock in ocfs2_fiemap 0 (5) 2024/10/17 03:19
[syzbot] Monthly ocfs2 report (Sep 2024) 0 (1) 2024/09/23 09:03
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 possible deadlock in ocfs2_fiemap 19 69d 249d 0/3 upstream: reported on 2024/10/11 18:44
linux-5.15 possible deadlock in ocfs2_fiemap 12 16d 249d 0/3 upstream: reported on 2024/10/11 15:39
Last patch testing requests (2)
Created Duration User Patch Repo Result
2024/10/17 03:19 19m lizhi.xu@windriver.com patch upstream OK log
2024/10/17 01:52 13m lizhi.xu@windriver.com patch upstream report log

Sample crash report:
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
6.12.0-rc2-syzkaller-00205-g1d227fcc7222 #0 Not tainted
------------------------------------------------------
syz-executor161/5226 is trying to acquire lock:
ffff88807e907398 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0xaa/0x120 mm/memory.c:6700

but task is already holding lock:
ffff8880720d0660 (&oi->ip_alloc_sem){++++}-{3:3}, at: ocfs2_fiemap+0x377/0xf80 fs/ocfs2/extent_map.c:755

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&oi->ip_alloc_sem){++++}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
       down_write+0x99/0x220 kernel/locking/rwsem.c:1577
       ocfs2_page_mkwrite+0x346/0xed0 fs/ocfs2/mmap.c:142
       do_page_mkwrite+0x198/0x480 mm/memory.c:3162
       do_shared_fault mm/memory.c:5358 [inline]
       do_fault mm/memory.c:5420 [inline]
       do_pte_missing mm/memory.c:3965 [inline]
       handle_pte_fault+0x11fa/0x6800 mm/memory.c:5751
       __handle_mm_fault mm/memory.c:5894 [inline]
       handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6062
       do_user_addr_fault arch/x86/mm/fault.c:1389 [inline]
       handle_page_fault arch/x86/mm/fault.c:1481 [inline]
       exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

-> #1 (sb_pagefaults){.+.+}-{0:0}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1716 [inline]
       sb_start_pagefault include/linux/fs.h:1881 [inline]
       ocfs2_page_mkwrite+0x222/0xed0 fs/ocfs2/mmap.c:122
       do_page_mkwrite+0x198/0x480 mm/memory.c:3162
       do_shared_fault mm/memory.c:5358 [inline]
       do_fault mm/memory.c:5420 [inline]
       do_pte_missing mm/memory.c:3965 [inline]
       handle_pte_fault+0x11fa/0x6800 mm/memory.c:5751
       __handle_mm_fault mm/memory.c:5894 [inline]
       handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6062
       do_user_addr_fault arch/x86/mm/fault.c:1389 [inline]
       handle_page_fault arch/x86/mm/fault.c:1481 [inline]
       exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

-> #0 (&mm->mmap_lock){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3161 [inline]
       check_prevs_add kernel/locking/lockdep.c:3280 [inline]
       validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
       __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
       __might_fault+0xc6/0x120 mm/memory.c:6700
       _inline_copy_to_user include/linux/uaccess.h:183 [inline]
       _copy_to_user+0x2a/0xb0 lib/usercopy.c:26
       copy_to_user include/linux/uaccess.h:216 [inline]
       fiemap_fill_next_extent+0x235/0x410 fs/ioctl.c:145
       ocfs2_fiemap+0x9f1/0xf80 fs/ocfs2/extent_map.c:796
       ioctl_fiemap fs/ioctl.c:220 [inline]
       do_vfs_ioctl+0x1bf8/0x2e40 fs/ioctl.c:841
       __do_sys_ioctl fs/ioctl.c:905 [inline]
       __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893
       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

other info that might help us debug this:

Chain exists of:
  &mm->mmap_lock --> sb_pagefaults --> &oi->ip_alloc_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  rlock(&oi->ip_alloc_sem);
                               lock(sb_pagefaults);
                               lock(&oi->ip_alloc_sem);
  rlock(&mm->mmap_lock);

 *** DEADLOCK ***

1 lock held by syz-executor161/5226:
 #0: ffff8880720d0660 (&oi->ip_alloc_sem){++++}-{3:3}, at: ocfs2_fiemap+0x377/0xf80 fs/ocfs2/extent_map.c:755

stack backtrace:
CPU: 0 UID: 0 PID: 5226 Comm: syz-executor161 Not tainted 6.12.0-rc2-syzkaller-00205-g1d227fcc7222 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206
 check_prev_add kernel/locking/lockdep.c:3161 [inline]
 check_prevs_add kernel/locking/lockdep.c:3280 [inline]
 validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
 __might_fault+0xc6/0x120 mm/memory.c:6700
 _inline_copy_to_user include/linux/uaccess.h:183 [inline]
 _copy_to_user+0x2a/0xb0 lib/usercopy.c:26
 copy_to_user include/linux/uaccess.h:216 [inline]
 fiemap_fill_next_extent+0x235/0x410 fs/ioctl.c:145
 ocfs2_fiemap+0x9f1/0xf80 fs/ocfs2/extent_map.c:796
 ioctl_fiemap fs/ioctl.c:220 [inline]
 do_vfs_ioctl+0x1bf8/0x2e40 fs/ioctl.c:841
 __do_sys_ioctl fs/ioctl.c:905 [inline]
 __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893
 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: 0033:0x7f29e7953939
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 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:00007ffc2a87c3b8 EFLAGS

Crashes (1246):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/11 12:41 upstream 1d227fcc7222 cd942402 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2024/09/29 07:51 upstream 3efc57369a0c ba29ff75 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/06/17 10:03 upstream 9afe652958c3 417d98fa .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in ocfs2_fiemap
2025/06/17 03:22 upstream 9afe652958c3 cfebc887 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/16 23:14 upstream e04c78d86a96 d1716036 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/16 13:19 upstream e04c78d86a96 d1716036 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/16 10:38 upstream e04c78d86a96 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/14 07:36 upstream 02adc1490e6d 0e8da31f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/14 04:57 upstream 02adc1490e6d 0e8da31f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/13 23:56 upstream 02adc1490e6d 0e8da31f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/10 23:30 upstream aef17cb3d3c4 5d7e17ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/10 13:19 upstream f09079bd04a9 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/10 06:00 upstream 19272b37aa4f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/06 08:58 upstream e271ed52b344 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/05 14:28 upstream ec7714e49479 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/04 04:45 upstream 5abc7438f1e9 a30356b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/03 05:11 upstream d00a83477e7a a30356b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/02 23:15 upstream d00a83477e7a b396b4bf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/06/01 12:01 upstream 4cb6c8af8591 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in ocfs2_fiemap
2025/06/01 08:01 upstream 4cb6c8af8591 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/05/28 17:38 upstream 3d413f0cfd7e 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/05/28 13:41 upstream feacb1774bd5 874a1386 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/05/27 12:49 upstream 785cdec46e92 874a1386 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_fiemap
2025/05/19 12:27 upstream a5806cd506af f41472b0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root possible deadlock in ocfs2_fiemap
2025/06/18 08:47 upstream 4663747812d1 e77fae15 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/06/16 02:15 upstream 08215f5486ec 5f4b362d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/06/13 12:14 upstream 27605c8c0f69 98683f8f .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/06/12 18:03 upstream 2c4a1f3fe03e 98683f8f .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/06/11 18:32 upstream aef17cb3d3c4 98683f8f .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/06/11 11:18 upstream aef17cb3d3c4 5d7e17ca .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/06/02 13:51 upstream cd2e103d57e5 aaaaf5ea .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/05/31 02:30 upstream 8477ab143069 3d2f584d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/05/30 06:36 upstream e0797d3b91de 3d2f584d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/05/28 12:11 upstream c89756bcf406 874a1386 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/05/28 01:18 upstream 914873bc7df9 874a1386 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/05/27 17:23 upstream 914873bc7df9 874a1386 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/05/27 16:08 upstream 914873bc7df9 874a1386 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/05/26 15:21 upstream 0ff41df1cb26 06877188 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2024/09/01 08:09 upstream 6cd90e5ea72f 1eda0d14 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2024/08/30 20:38 upstream 20371ba12063 db150e23 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_fiemap
2025/06/17 19:11 linux-next 4325743c7e20 417d98fa .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root possible deadlock in ocfs2_fiemap
2025/06/09 03:30 linux-next 475c850a7fdd 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root possible deadlock in ocfs2_fiemap
2025/06/01 09:04 linux-next 3a83b350b5be 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root possible deadlock in ocfs2_fiemap
2025/06/18 00:11 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 39dfc971e42d 417d98fa .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_fiemap
2025/06/15 16:23 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 39dfc971e42d 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_fiemap
2025/06/15 14:09 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 39dfc971e42d 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_fiemap
2025/06/15 10:56 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 39dfc971e42d 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_fiemap
2025/06/15 09:38 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 39dfc971e42d 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_fiemap
2025/06/15 00:47 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 39dfc971e42d 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_fiemap
2025/06/13 00:34 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 19272b37aa4f 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_fiemap
2025/06/08 04:03 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci d7fa1af5b33e 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_fiemap
2025/06/07 06:04 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci d7fa1af5b33e 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_fiemap
2025/05/30 20:52 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci d7fa1af5b33e 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_fiemap
2025/05/30 13:11 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci d7fa1af5b33e 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_fiemap
2025/05/30 02:35 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci d7fa1af5b33e 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_fiemap
2025/05/27 20:04 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci d7fa1af5b33e 874a1386 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_fiemap
* Struck through repros no longer work on HEAD.