syzbot


possible deadlock in ocfs2_calc_xattr_init (2)

Status: upstream: reported on 2025/07/12 15:36
Reported-by: syzbot+58526ea8b63f3d5f4b8a@syzkaller.appspotmail.com
First crash: 51d, last: 24d
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 possible deadlock in ocfs2_calc_xattr_init 4 5 16d 50d 0/2 upstream: reported on 2025/07/13 05:28
upstream possible deadlock in ocfs2_calc_xattr_init ocfs2 4 175 10d 333d 0/29 upstream: reported on 2024/10/04 01:35
linux-6.1 possible deadlock in ocfs2_calc_xattr_init 4 6 239d 273d 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 176d 353d 0/3 auto-obsoleted due to no activity on 2025/06/17 06:29

Sample crash report:
JBD2: Ignoring recovery information on journal
ocfs2: Mounting device (7,4) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
5.15.189-syzkaller #0 Not tainted
------------------------------------------------------
syz.4.91/4739 is trying to acquire lock:
ffff888060e2bff8 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_calc_xattr_init+0x204/0xd70 fs/ocfs2/xattr.c:631

but task is already holding lock:
ffff88805f10a648 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
ffff88805f10a648 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2){+.+.}-{3:3}, at: ocfs2_reserve_suballoc_bits+0x161/0x4350 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+0x38/0x60 kernel/locking/rwsem.c:1551
       inode_lock include/linux/fs.h:787 [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+0x130f/0x3e40 fs/ocfs2/inode.c:1216
       evict+0x485/0x870 fs/inode.c:647
       d_delete_notify include/linux/fsnotify.h:267 [inline]
       vfs_rmdir+0x3b4/0x430 fs/namei.c:4162
       do_rmdir+0x295/0x710 fs/namei.c:4210
       __do_sys_unlinkat fs/namei.c:4390 [inline]
       __se_sys_unlinkat fs/namei.c:4384 [inline]
       __x64_sys_unlinkat+0xc0/0xe0 fs/namei.c:4384
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #2 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{3:3}:
       down_write+0x38/0x60 kernel/locking/rwsem.c:1551
       inode_lock include/linux/fs.h:787 [inline]
       ocfs2_del_inode_from_orphan+0x131/0x730 fs/ocfs2/namei.c:2713
       ocfs2_dio_end_io_write fs/ocfs2/aops.c:2333 [inline]
       ocfs2_dio_end_io+0x475/0x10f0 fs/ocfs2/aops.c:2431
       dio_complete+0x249/0x720 fs/direct-io.c:272
       do_blockdev_direct_IO fs/direct-io.c:1336 [inline]
       __blockdev_direct_IO+0x30a7/0x3c90 fs/direct-io.c:1368
       ocfs2_direct_IO+0x23e/0x2b0 fs/ocfs2/aops.c:2468
       generic_file_direct_write+0x22c/0x490 mm/filemap.c:3687
       __generic_file_write_iter+0x2b1/0x4e0 mm/filemap.c:3869
       ocfs2_file_write_iter+0x1578/0x1cf0 fs/ocfs2/file.c:2472
       do_iter_readv_writev+0x497/0x600 fs/read_write.c:-1
       do_iter_write+0x205/0x7b0 fs/read_write.c:855
       iter_file_splice_write+0x65f/0xc40 fs/splice.c:689
       do_splice_from fs/splice.c:767 [inline]
       direct_splice_actor+0xe1/0x130 fs/splice.c:936
       splice_direct_to_actor+0x4dc/0xb50 fs/splice.c:891
       do_splice_direct+0x1b9/0x2c0 fs/splice.c:979
       do_sendfile+0x5d5/0xec0 fs/read_write.c:1249
       __do_sys_sendfile64 fs/read_write.c:1317 [inline]
       __se_sys_sendfile64+0x13b/0x190 fs/read_write.c:1303
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #1 (&oi->ip_alloc_sem){++++}-{3:3}:
       down_write+0x38/0x60 kernel/locking/rwsem.c:1551
       ocfs2_try_remove_refcount_tree+0xb3/0x320 fs/ocfs2/refcounttree.c:932
       ocfs2_truncate_file+0xda2/0x13b0 fs/ocfs2/file.c:517
       ocfs2_setattr+0x143b/0x1a10 fs/ocfs2/file.c:1215
       notify_change+0xbcd/0xee0 fs/attr.c:505
       do_truncate+0x197/0x220 fs/open.c:65
       handle_truncate fs/namei.c:3265 [inline]
       do_open fs/namei.c:3612 [inline]
       path_openat+0x28af/0x2f30 fs/namei.c:3742
       do_filp_open+0x1b3/0x3e0 fs/namei.c:3769
       do_sys_openat2+0x142/0x4a0 fs/open.c:1253
       do_sys_open fs/open.c:1269 [inline]
       __do_sys_creat fs/open.c:1345 [inline]
       __se_sys_creat fs/open.c:1339 [inline]
       __x64_sys_creat+0x8c/0xb0 fs/open.c:1339
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #0 (&oi->ip_xattr_sem){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain kernel/locking/lockdep.c:3788 [inline]
       __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
       lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
       down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498
       ocfs2_calc_xattr_init+0x204/0xd70 fs/ocfs2/xattr.c:631
       ocfs2_mknod+0xc7f/0x22b0 fs/ocfs2/namei.c:330
       ocfs2_create+0x192/0x410 fs/ocfs2/namei.c:674
       lookup_open fs/namei.c:3462 [inline]
       open_last_lookups fs/namei.c:3532 [inline]
       path_openat+0x11e1/0x2f30 fs/namei.c:3739
       do_filp_open+0x1b3/0x3e0 fs/namei.c:3769
       do_sys_openat2+0x142/0x4a0 fs/open.c:1253
       do_sys_open fs/open.c:1269 [inline]
       __do_sys_open fs/open.c:1277 [inline]
       __se_sys_open fs/open.c:1273 [inline]
       __x64_sys_open+0x11b/0x140 fs/open.c:1273
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

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.4.91/4739:
 #0: ffff888022954460 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:377
 #1: ffff888060e2c2c8 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff888060e2c2c8 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: open_last_lookups fs/namei.c:3529 [inline]
 #1: ffff888060e2c2c8 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: path_openat+0x7f3/0x2f30 fs/namei.c:3739
 #2: ffff88805f10a648 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #2: ffff88805f10a648 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2){+.+.}-{3:3}, at: ocfs2_reserve_suballoc_bits+0x161/0x4350 fs/ocfs2/suballoc.c:782

stack backtrace:
CPU: 1 PID: 4739 Comm: syz.4.91 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain kernel/locking/lockdep.c:3788 [inline]
 __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498
 ocfs2_calc_xattr_init+0x204/0xd70 fs/ocfs2/xattr.c:631
 ocfs2_mknod+0xc7f/0x22b0 fs/ocfs2/namei.c:330
 ocfs2_create+0x192/0x410 fs/ocfs2/namei.c:674
 lookup_open fs/namei.c:3462 [inline]
 open_last_lookups fs/namei.c:3532 [inline]
 path_openat+0x11e1/0x2f30 fs/namei.c:3739
 do_filp_open+0x1b3/0x3e0 fs/namei.c:3769
 do_sys_openat2+0x142/0x4a0 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_open fs/open.c:1277 [inline]
 __se_sys_open fs/open.c:1273 [inline]
 __x64_sys_open+0x11b/0x140 fs/open.c:1273
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fe597c2cbe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe595e94038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fe597e53fa0 RCX: 00007fe597c2cbe9
RDX: 0000000000000000 RSI: 000000000014927e RDI: 0000200000000180
RBP: 00007fe597cafe19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe597e54038 R14: 00007fe597e53fa0 R15: 00007ffd3480c2b8
 </TASK>

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/08 13:52 linux-5.15.y c79648372d02 6a893178 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ocfs2_calc_xattr_init
2025/08/01 16:19 linux-5.15.y c79648372d02 40127d41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ocfs2_calc_xattr_init
2025/07/31 21:37 linux-5.15.y c79648372d02 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ocfs2_calc_xattr_init
2025/07/30 17:48 linux-5.15.y c79648372d02 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ocfs2_calc_xattr_init
2025/07/12 15:35 linux-5.15.y 2f693b607545 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ocfs2_calc_xattr_init
* Struck through repros no longer work on HEAD.