syzbot


possible deadlock in ocfs2_calc_xattr_init (2)

Status: upstream: reported on 2025/09/21 08:44
Reported-by: syzbot+cd2e0cbc5b21ab15c2ca@syzkaller.appspotmail.com
First crash: 234d, last: 15d
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 possible deadlock in ocfs2_calc_xattr_init 4 20 37d 304d 0/2 upstream: reported on 2025/07/13 05:28
linux-5.15 possible deadlock in ocfs2_calc_xattr_init (2) 4 13 53d 305d 0/3 upstream: reported on 2025/07/12 15:36
upstream possible deadlock in ocfs2_calc_xattr_init ocfs2 4 376 27d 586d 0/29 upstream: reported on 2024/10/04 01:35
linux-6.1 possible deadlock in ocfs2_calc_xattr_init 4 6 492d 526d 0/3 auto-obsoleted due to no activity on 2025/04/15 19:53
linux-5.15 possible deadlock in ocfs2_calc_xattr_init 4 14 430d 606d 0/3 auto-obsoleted due to no activity on 2025/06/17 06:29

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.3.21/4443 is trying to acquire lock:
ffff888054d9eab8 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_calc_xattr_init+0x204/0xd90 fs/ocfs2/xattr.c:631

but task is already holding lock:
ffff8880743709c8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff8880743709c8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2){+.+.}-{3:3}, at: ocfs2_reserve_suballoc_bits+0x16d/0x4810 fs/ocfs2/suballoc.c:782

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2){+.+.}-{3:3}:
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:758 [inline]
       ocfs2_remove_inode fs/ocfs2/inode.c:655 [inline]
       ocfs2_wipe_inode fs/ocfs2/inode.c:818 [inline]
       ocfs2_delete_inode fs/ocfs2/inode.c:1079 [inline]
       ocfs2_evict_inode+0x163f/0x4630 fs/ocfs2/inode.c:1219
       evict+0x4c9/0x8d0 fs/inode.c:705
       d_delete_notify include/linux/fsnotify.h:267 [inline]
       vfs_rmdir+0x397/0x4d0 fs/namei.c:4212
       do_rmdir+0x29a/0x5c0 fs/namei.c:4260
       __do_sys_unlinkat fs/namei.c:4440 [inline]
       __se_sys_unlinkat fs/namei.c:4434 [inline]
       __x64_sys_unlinkat+0xc0/0xe0 fs/namei.c:4434
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #2 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{3:3}:
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:758 [inline]
       ocfs2_del_inode_from_orphan+0x12b/0x7a0 fs/ocfs2/namei.c:2713
       ocfs2_dio_end_io_write fs/ocfs2/aops.c:2333 [inline]
       ocfs2_dio_end_io+0x540/0x1200 fs/ocfs2/aops.c:2431
       dio_complete+0x251/0x710 fs/direct-io.c:271
       __blockdev_direct_IO+0x2f25/0x3570 fs/direct-io.c:1320
       ocfs2_direct_IO+0x233/0x2a0 fs/ocfs2/aops.c:2468
       generic_file_direct_write+0x10f/0x330 mm/filemap.c:3787
       __generic_file_write_iter+0x15f/0x2a0 mm/filemap.c:3945
       ocfs2_file_write_iter+0x1660/0x1f00 fs/ocfs2/file.c:2469
       do_iter_readv_writev fs/read_write.c:-1 [inline]
       do_iter_write+0x642/0xb10 fs/read_write.c:861
       iter_file_splice_write+0x699/0xcc0 fs/splice.c:685
       do_splice_from fs/splice.c:763 [inline]
       direct_splice_actor+0xe1/0x130 fs/splice.c:950
       splice_direct_to_actor+0x48b/0xb90 fs/splice.c:896
       do_splice_direct+0x1ce/0x2f0 fs/splice.c:1002
       do_sendfile+0x5f3/0xea0 fs/read_write.c:1255
       __do_sys_sendfile64 fs/read_write.c:1323 [inline]
       __se_sys_sendfile64+0x141/0x1a0 fs/read_write.c:1309
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #1 (&oi->ip_alloc_sem){++++}-{3:3}:
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       ocfs2_try_remove_refcount_tree+0xb3/0x340 fs/ocfs2/refcounttree.c:932
       ocfs2_truncate_file+0xe35/0x1580 fs/ocfs2/file.c:517
       ocfs2_setattr+0x16b8/0x1d30 fs/ocfs2/file.c:1212
       notify_change+0xc74/0xf40 fs/attr.c:499
       do_truncate+0x1ac/0x240 fs/open.c:65
       do_coredump+0x2043/0x22f0 fs/coredump.c:801
       get_signal+0x10aa/0x1350 kernel/signal.c:2857
       arch_do_signal_or_restart+0xc4/0x1350 arch/x86/kernel/signal.c:871
       exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
       exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
       irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:316
       asm_exc_stack_segment+0x22/0x30 arch/x86/include/asm/idtentry.h:601

-> #0 (&oi->ip_xattr_sem){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3090 [inline]
       check_prevs_add kernel/locking/lockdep.c:3209 [inline]
       validate_chain kernel/locking/lockdep.c:3825 [inline]
       __lock_acquire+0x2d07/0x7d10 kernel/locking/lockdep.c:5049
       lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662
       down_read+0x42/0x2d0 kernel/locking/rwsem.c:1520
       ocfs2_calc_xattr_init+0x204/0xd90 fs/ocfs2/xattr.c:631
       ocfs2_mknod+0xd59/0x25b0 fs/ocfs2/namei.c:330
       ocfs2_create+0x1b6/0x4b0 fs/ocfs2/namei.c:674
       lookup_open fs/namei.c:3490 [inline]
       open_last_lookups fs/namei.c:3558 [inline]
       path_openat+0x1181/0x2ee0 fs/namei.c:3788
       do_filp_open+0x1f1/0x430 fs/namei.c:3818
       do_sys_openat2+0x150/0x4b0 fs/open.c:1320
       do_sys_open fs/open.c:1336 [inline]
       __do_sys_open fs/open.c:1344 [inline]
       __se_sys_open fs/open.c:1340 [inline]
       __x64_sys_open+0x11b/0x140 fs/open.c:1340
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

Chain exists of:
  &oi->ip_xattr_sem --> &ocfs2_sysfile_lock_key[args->fi_sysfile_type] --> &ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2);
  lock(&oi->ip_xattr_sem);

 *** DEADLOCK ***

3 locks held by syz.3.21/4443:
 #0: ffff88807d2ba460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:402
 #1: ffff888054d9ed88 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff888054d9ed88 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: open_last_lookups fs/namei.c:3555 [inline]
 #1: ffff888054d9ed88 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: path_openat+0x7d2/0x2ee0 fs/namei.c:3788
 #2: ffff8880743709c8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #2: ffff8880743709c8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2){+.+.}-{3:3}, at: ocfs2_reserve_suballoc_bits+0x16d/0x4810 fs/ocfs2/suballoc.c:782

stack backtrace:
CPU: 0 PID: 4443 Comm: syz.3.21 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2170
 check_prev_add kernel/locking/lockdep.c:3090 [inline]
 check_prevs_add kernel/locking/lockdep.c:3209 [inline]
 validate_chain kernel/locking/lockdep.c:3825 [inline]
 __lock_acquire+0x2d07/0x7d10 kernel/locking/lockdep.c:5049
 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662
 down_read+0x42/0x2d0 kernel/locking/rwsem.c:1520
 ocfs2_calc_xattr_init+0x204/0xd90 fs/ocfs2/xattr.c:631
 ocfs2_mknod+0xd59/0x25b0 fs/ocfs2/namei.c:330
 ocfs2_create+0x1b6/0x4b0 fs/ocfs2/namei.c:674
 lookup_open fs/namei.c:3490 [inline]
 open_last_lookups fs/namei.c:3558 [inline]
 path_openat+0x1181/0x2ee0 fs/namei.c:3788
 do_filp_open+0x1f1/0x430 fs/namei.c:3818
 do_sys_openat2+0x150/0x4b0 fs/open.c:1320
 do_sys_open fs/open.c:1336 [inline]
 __do_sys_open fs/open.c:1344 [inline]
 __se_sys_open fs/open.c:1340 [inline]
 __x64_sys_open+0x11b/0x140 fs/open.c:1340
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcbcc19cdd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcbcd0b2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fcbcc415fa0 RCX: 00007fcbcc19cdd9
RDX: 000000000000002a RSI: 0000000400141042 RDI: 0000200000000040
RBP: 00007fcbcc232d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcbcc416038 R14: 00007fcbcc415fa0 R15: 00007ffcdee8d498
 </TASK>
bridge0: port 3(syz_tun) entered disabled state
infiniband syz1: set down
device syz_tun left promiscuous mode
bridge0: port 3(syz_tun) entered disabled state
ocfs2: Unmounting device (7,3) on (node local)

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/28 05:44 linux-6.1.y 7c87defbd336 ce741359 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_calc_xattr_init
2026/02/09 02:31 linux-6.1.y 0182cb5b74ee 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_calc_xattr_init
2026/01/18 01:19 linux-6.1.y cd9b81672742 20d37d28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_calc_xattr_init
2025/10/27 06:44 linux-6.1.y 8e6e2188d949 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_calc_xattr_init
2025/09/21 08:43 linux-6.1.y 363a599da6d9 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_calc_xattr_init
* Struck through repros no longer work on HEAD.