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======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.4.146/4966 is trying to acquire lock:
ffff888058019808 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
ffff888058019808 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{3:3}, at: ocfs2_remove_btree_range+0x674/0x15e0 fs/ocfs2/alloc.c:5742
but task is already holding lock:
ffff888058013f60 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_truncate_file+0x31e/0x1460 fs/ocfs2/file.c:467
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #4 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}:
down_write+0x38/0x60 kernel/locking/rwsem.c:1551
ocfs2_create_local_dquot+0x199/0x1850 fs/ocfs2/quota_local.c:1224
ocfs2_acquire_dquot+0x7ed/0xb10 fs/ocfs2/quota_global.c:871
dqget+0x778/0xeb0 fs/quota/dquot.c:988
__dquot_initialize+0x3c3/0xcd0 fs/quota/dquot.c:1517
ocfs2_get_init_inode+0x144/0x1b0 fs/ocfs2/namei.c:202
ocfs2_mknod+0x8ab/0x2510 fs/ocfs2/namei.c:310
ocfs2_mkdir+0x192/0x420 fs/ocfs2/namei.c:657
vfs_mkdir+0x387/0x570 fs/namei.c:4073
do_mkdirat+0x1df/0x5b0 fs/namei.c:4098
__do_sys_mkdirat fs/namei.c:4113 [inline]
__se_sys_mkdirat fs/namei.c:4111 [inline]
__x64_sys_mkdirat+0x85/0x90 fs/namei.c:4111
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
-> #3 (&dquot->dq_lock){+.+.}-{3:3}
:
__mutex_lock_common+0x1e3/0x2400 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
dquot_commit+0x5a/0x410 fs/quota/dquot.c:507
ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6210
mark_dquot_dirty fs/quota/dquot.c:372 [inline]
mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412
__dquot_free_space+0x7ca/0xb90 fs/quota/dquot.c:1942
dquot_free_space_nodirty include/linux/quotaops.h:376 [inline]
dquot_free_space include/linux/quotaops.h:381 [inline]
dquot_free_block include/linux/quotaops.h:392 [inline]
ext4_mb_clear_bb fs/ext4/mballoc.c:6165 [inline]
ext4_free_blocks+0x1b2b/0x24d0 fs/ext4/mballoc.c:6295
ext4_remove_blocks fs/ext4/extents.c:2525 [inline]
ext4_ext_rm_leaf fs/ext4/extents.c:2691 [inline]
ext4_ext_remove_space+0x1f86/0x42b0 fs/ext4/extents.c:2939
ext4_ext_truncate+0x192/0x240 fs/ext4/extents.c:4479
ext4_truncate+0xa09/0x10f0 fs/ext4/inode.c:4256
ext4_process_orphan+0x1cb/0x300 fs/ext4/orphan.c:337
ext4_orphan_cleanup+0xad2/0x1320 fs/ext4/orphan.c:472
ext4_fill_super+0x8e25/0x95a0 fs/ext4/super.c:5000
mount_bdev+0x287/0x3c0 fs/super.c:1400
legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
vfs_get_tree+0x88/0x270 fs/super.c:1530
do_new_mount+0x24a/0xa40 fs/namespace.c:3034
do_mount fs/namespace.c:3377 [inline]
__do_sys_mount fs/namespace.c:3585 [inline]
__se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
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 (&ei->i_data_sem){++++}-{3:3}:
down_write+0x38/0x60 kernel/locking/rwsem.c:1551
ext4_truncate+0x97f/0x10f0 fs/ext4/inode.c:4251
ext4_setattr+0xffe/0x19e0 fs/ext4/inode.c:5601
notify_change+0xbcd/0xee0 fs/attr.c:505
do_truncate+0x1ac/0x240 fs/open.c:65
do_sys_ftruncate+0x31b/0x3d0 fs/open.c:193
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 (jbd2_handle){++++}-{0:0}:
jbd2_journal_lock_updates+0xa4/0x390 fs/jbd2/transaction.c:881
__ocfs2_flush_truncate_log+0x2ba/0x1110 fs/ocfs2/alloc.c:6027
ocfs2_flush_truncate_log+0x4b/0x60 fs/ocfs2/alloc.c:6074
ocfs2_sync_fs+0x119/0x330 fs/ocfs2/super.c:403
sync_filesystem+0x1be/0x220 fs/sync.c:66
generic_shutdown_super+0x6b/0x300 fs/super.c:448
kill_block_super+0x7c/0xe0 fs/super.c:1427
deactivate_locked_super+0x93/0xf0 fs/super.c:335
cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148
task_work_run+0x125/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #0 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{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+0x2c42/0x7d10 kernel/locking/lockdep.c:5012
lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
down_write+0x38/0x60 kernel/locking/rwsem.c:1551
inode_lock include/linux/fs.h:787 [inline]
ocfs2_remove_btree_range+0x674/0x15e0 fs/ocfs2/alloc.c:5742
ocfs2_commit_truncate+0xb68/0x1d50 fs/ocfs2/alloc.c:7346
ocfs2_truncate_file+0xd05/0x1460 fs/ocfs2/file.c:505
ocfs2_setattr+0x14dd/0x1ad0 fs/ocfs2/file.c:1215
notify_change+0xbcd/0xee0 fs/attr.c:505
do_truncate+0x1ac/0x240 fs/open.c:65
vfs_truncate+0x262/0x2f0 fs/open.c:111
do_sys_truncate+0xf2/0x1c0 fs/open.c:134
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:
&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8 --> &dquot->dq_lock --> &ocfs2_quota_ip_alloc_sem_key
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&ocfs2_quota_ip_alloc_sem_key);
lock(&dquot->dq_lock);
lock(&ocfs2_quota_ip_alloc_sem_key);
lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8);
*** DEADLOCK ***
3 locks held by syz.4.146/4966:
#0: ffff88807b648460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:386
#1: ffff8880580142c8 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
#1: ffff8880580142c8 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: do_truncate+0x198/0x240 fs/open.c:63
#2: ffff888058013f60 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_truncate_file+0x31e/0x1460 fs/ocfs2/file.c:467
stack backtrace:
CPU: 0 PID: 4966 Comm: syz.4.146 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
<TASK>
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
check_noncircular+0x296/0x330 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+0x2c42/0x7d10 kernel/locking/lockdep.c:5012
lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
down_write+0x38/0x60 kernel/locking/rwsem.c:1551
inode_lock include/linux/fs.h:787 [inline]
ocfs2_remove_btree_range+0x674/0x15e0 fs/ocfs2/alloc.c:5742
ocfs2_commit_truncate+0xb68/0x1d50 fs/ocfs2/alloc.c:7346
ocfs2_truncate_file+0xd05/0x1460 fs/ocfs2/file.c:505
ocfs2_setattr+0x14dd/0x1ad0 fs/ocfs2/file.c:1215
notify_change+0xbcd/0xee0 fs/attr.c:505
do_truncate+0x1ac/0x240 fs/open.c:65
vfs_truncate+0x262/0x2f0 fs/open.c:111
do_sys_truncate+0xf2/0x1c0 fs/open.c:134
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: 0033:0x7fb48e1bc819
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:00007fb48c3f5028 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 00007fb48e436090 RCX: 00007fb48e1bc819
RDX: 0000000000000000 RSI: 0000000000001bf8 RDI: 0000200000000280
RBP: 00007fb48e252c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb48e436128 R14: 00007fb48e436090 R15: 00007ffdf4189e88
</TASK>
| Time | Kernel | Commit | Syzkaller | Config | Log | Report | Syz repro | C repro | VM info | Assets (help?) | Manager | Title |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026/04/14 14:32 | linux-5.15.y | 91d48252ad4b | 362d1323 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | possible deadlock in ocfs2_remove_btree_range | ||
| 2026/03/31 02:34 | linux-5.15.y | 91d48252ad4b | d0af506e | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | possible deadlock in ocfs2_remove_btree_range | ||
| 2026/03/09 18:47 | linux-5.15.y | 91d48252ad4b | 176bead5 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | possible deadlock in ocfs2_remove_btree_range | ||
| 2026/02/08 13:35 | linux-5.15.y | 7b232985052f | 4c131dc4 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-5-15-kasan | possible deadlock in ocfs2_remove_btree_range |