[v5.15] possible deadlock in ocfs2_write_begin_nolock

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syzbot

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Oct 27, 2024, 12:30:26 AM10/27/24
to syzkaller...@googlegroups.com
Hello,

syzbot found the following issue on:

HEAD commit: 74cdd62cb470 Linux 5.15.169
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14069230580000
kernel config: https://syzkaller.appspot.com/x/.config?x=5a9622b27b0be51a
dashboard link: https://syzkaller.appspot.com/bug?extid=1782a3a587bc53dc10cf
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/100cab3ab8cf/disk-74cdd62c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8eab59bf613d/vmlinux-74cdd62c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e815c18aac36/bzImage-74cdd62c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1782a3...@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
5.15.169-syzkaller #0 Not tainted
------------------------------------------------------
syz.8.3444/22574 is trying to acquire lock:
ffff88806409c650 (sb_internal#3){.+.+}-{0:0}, at: ocfs2_write_begin_inline fs/ocfs2/aops.c:1482 [inline]
ffff88806409c650 (sb_internal#3){.+.+}-{0:0}, at: ocfs2_try_to_write_inline_data fs/ocfs2/aops.c:1585 [inline]
ffff88806409c650 (sb_internal#3){.+.+}-{0:0}, at: ocfs2_write_begin_nolock+0x2242/0x4d20 fs/ocfs2/aops.c:1671

but task is already holding lock:
ffff8880747e3f60 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_write_begin+0x1cb/0x390 fs/ocfs2/aops.c:1903

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
down_write+0x38/0x60 kernel/locking/rwsem.c:1551
ocfs2_try_remove_refcount_tree+0xb2/0x330 fs/ocfs2/refcounttree.c:932
ocfs2_xattr_set+0xa4b/0x1930 fs/ocfs2/xattr.c:3674
ocfs2_set_acl+0x4cb/0x570 fs/ocfs2/acl.c:254
ocfs2_iop_set_acl+0x252/0x3c0 fs/ocfs2/acl.c:285
set_posix_acl fs/posix_acl.c:947 [inline]
posix_acl_xattr_set+0x33b/0x3a0 fs/posix_acl.c:966
__vfs_removexattr+0x3ce/0x410 fs/xattr.c:470
__vfs_removexattr_locked+0x1fe/0x410 fs/xattr.c:505
vfs_removexattr+0xff/0x2a0 fs/xattr.c:527
removexattr fs/xattr.c:857 [inline]
path_removexattr+0x22a/0x320 fs/xattr.c:871
__do_sys_lremovexattr fs/xattr.c:891 [inline]
__se_sys_lremovexattr fs/xattr.c:888 [inline]
__x64_sys_lremovexattr+0x59/0x70 fs/xattr.c:888
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #3 (&oi->ip_xattr_sem){++++}-{3:3}:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
down_read+0x45/0x2e0 kernel/locking/rwsem.c:1498
ocfs2_init_acl+0x398/0x930 fs/ocfs2/acl.c:365
ocfs2_mknod+0x1e8f/0x2cd0 fs/ocfs2/namei.c:408
ocfs2_create+0x194/0x430 fs/ocfs2/namei.c:672
lookup_open fs/namei.c:3462 [inline]
open_last_lookups fs/namei.c:3532 [inline]
path_openat+0x130a/0x2f20 fs/namei.c:3739
do_filp_open+0x21c/0x460 fs/namei.c:3769
do_sys_openat2+0x13b/0x4f0 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+0x221/0x270 fs/open.c:1273
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #2 (jbd2_handle){++++}-{0:0}:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
start_this_handle+0x12e1/0x1570 fs/jbd2/transaction.c:464
jbd2__journal_start+0x2d1/0x5c0 fs/jbd2/transaction.c:521
jbd2_journal_start+0x25/0x30 fs/jbd2/transaction.c:560
ocfs2_start_trans+0x3c2/0x6f0 fs/ocfs2/journal.c:354
ocfs2_shutdown_local_alloc+0x214/0xa90 fs/ocfs2/localalloc.c:416
ocfs2_dismount_volume+0x1db/0x8b0 fs/ocfs2/super.c:1882
generic_shutdown_super+0x130/0x310 fs/super.c:475
kill_block_super+0x7a/0xe0 fs/super.c:1427
deactivate_locked_super+0xa0/0x110 fs/super.c:335
cleanup_mnt+0x44e/0x500 fs/namespace.c:1143
task_work_run+0x129/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #1 (&journal->j_trans_barrier){.+.+}-{3:3}:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
down_read+0x45/0x2e0 kernel/locking/rwsem.c:1498
ocfs2_start_trans+0x3b7/0x6f0 fs/ocfs2/journal.c:352
ocfs2_shutdown_local_alloc+0x214/0xa90 fs/ocfs2/localalloc.c:416
ocfs2_dismount_volume+0x1db/0x8b0 fs/ocfs2/super.c:1882
generic_shutdown_super+0x130/0x310 fs/super.c:475
kill_block_super+0x7a/0xe0 fs/super.c:1427
deactivate_locked_super+0xa0/0x110 fs/super.c:335
cleanup_mnt+0x44e/0x500 fs/namespace.c:1143
task_work_run+0x129/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #0 (sb_internal#3){.+.+}-{0:0}:
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
__lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write include/linux/fs.h:1813 [inline]
sb_start_intwrite include/linux/fs.h:1930 [inline]
ocfs2_start_trans+0x2b2/0x6f0 fs/ocfs2/journal.c:350
ocfs2_write_begin_inline fs/ocfs2/aops.c:1482 [inline]
ocfs2_try_to_write_inline_data fs/ocfs2/aops.c:1585 [inline]
ocfs2_write_begin_nolock+0x2242/0x4d20 fs/ocfs2/aops.c:1671
ocfs2_write_begin+0x1fd/0x390 fs/ocfs2/aops.c:1905
generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785
__generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912
ocfs2_file_write_iter+0x17d5/0x1fa0 fs/ocfs2/file.c:2459
call_write_iter include/linux/fs.h:2174 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0xacd/0xe50 fs/read_write.c:594
ksys_pwrite64 fs/read_write.c:701 [inline]
__do_sys_pwrite64 fs/read_write.c:711 [inline]
__se_sys_pwrite64 fs/read_write.c:708 [inline]
__x64_sys_pwrite64+0x1a9/0x230 fs/read_write.c:708
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0

other info that might help us debug this:

Chain exists of:
sb_internal#3 --> &oi->ip_xattr_sem --> &ocfs2_file_ip_alloc_sem_key

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&ocfs2_file_ip_alloc_sem_key);
lock(&oi->ip_xattr_sem);
lock(&ocfs2_file_ip_alloc_sem_key);
lock(sb_internal#3);

*** DEADLOCK ***

3 locks held by syz.8.3444/22574:
#0: ffff88806409c460 (sb_writers#24){.+.+}-{0:0}, at: vfs_write+0x29a/0xe50 fs/read_write.c:590
#1: ffff8880747e42c8 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline]
#1: ffff8880747e42c8 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: ocfs2_file_write_iter+0x446/0x1fa0 fs/ocfs2/file.c:2391
#2: ffff8880747e3f60 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_write_begin+0x1cb/0x390 fs/ocfs2/aops.c:1903

stack backtrace:
CPU: 0 PID: 22574 Comm: syz.8.3444 Not tainted 5.15.169-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
check_noncircular+0x2f8/0x3b0 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+0x1649/0x5930 kernel/locking/lockdep.c:3788
__lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write include/linux/fs.h:1813 [inline]
sb_start_intwrite include/linux/fs.h:1930 [inline]
ocfs2_start_trans+0x2b2/0x6f0 fs/ocfs2/journal.c:350
ocfs2_write_begin_inline fs/ocfs2/aops.c:1482 [inline]
ocfs2_try_to_write_inline_data fs/ocfs2/aops.c:1585 [inline]
ocfs2_write_begin_nolock+0x2242/0x4d20 fs/ocfs2/aops.c:1671
ocfs2_write_begin+0x1fd/0x390 fs/ocfs2/aops.c:1905
generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785
__generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912
ocfs2_file_write_iter+0x17d5/0x1fa0 fs/ocfs2/file.c:2459
call_write_iter include/linux/fs.h:2174 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0xacd/0xe50 fs/read_write.c:594
ksys_pwrite64 fs/read_write.c:701 [inline]
__do_sys_pwrite64 fs/read_write.c:711 [inline]
__se_sys_pwrite64 fs/read_write.c:708 [inline]
__x64_sys_pwrite64+0x1a9/0x230 fs/read_write.c:708
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f4ce1442719
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:00007f4cdf899038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 00007f4ce15fa058 RCX: 00007f4ce1442719
RDX: 0000000000000001 RSI: 0000000020000280 RDI: 0000000000000004
RBP: 00007f4ce14b532e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f4ce15fa058 R15: 00007fff2449ffd8
</TASK>


---
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If the report is already addressed, let syzbot know by replying with:
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If you want to overwrite report's subsystems, reply with:
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syzbot

unread,
Dec 5, 2025, 12:18:28 PM12/5/25
to syzkaller...@googlegroups.com
syzbot has found a reproducer for the following issue on:

HEAD commit: cc5ec8769306 Linux 5.15.196
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=177d7cc2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e1bb6d24ef2164eb
dashboard link: https://syzkaller.appspot.com/bug?extid=1782a3a587bc53dc10cf
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10fd7cc2580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13f8f01a580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c71c660545b2/disk-cc5ec876.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4f011826cca6/vmlinux-cc5ec876.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8ccd1a2c3f8c/bzImage-cc5ec876.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/421521a5edd4/mount_0.gz
fsck result: OK (log: https://syzkaller.appspot.com/x/fsck.log?x=17a3c41a580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1782a3...@syzkaller.appspotmail.com

JBD2: Ignoring recovery information on journal
jbd2_journal_bmap: journal block not found at offset 32 on loop0-75
JBD2: bad block at offset 32
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.17/4317 is trying to acquire lock:
ffff88807d768650 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_write_begin_inline fs/ocfs2/aops.c:1482 [inline]
ffff88807d768650 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_try_to_write_inline_data fs/ocfs2/aops.c:1585 [inline]
ffff88807d768650 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_write_begin_nolock+0x1c5e/0x4180 fs/ocfs2/aops.c:1671

but task is already holding lock:
ffff88805d1e3f60 (&oi->ip_alloc_sem){++++}-{3:3}, at: ocfs2_write_begin+0x18a/0x300 fs/ocfs2/aops.c:1903

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&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_xattr_set+0x592/0x11e0 fs/ocfs2/xattr.c:3673
ocfs2_set_acl+0x4e1/0x590 fs/ocfs2/acl.c:254
ocfs2_iop_set_acl+0x16f/0x270 fs/ocfs2/acl.c:285
set_posix_acl fs/posix_acl.c:947 [inline]
posix_acl_xattr_set+0x36f/0x3e0 fs/posix_acl.c:966
__vfs_removexattr+0x3b7/0x3f0 fs/xattr.c:470
__vfs_removexattr_locked+0x1e4/0x230 fs/xattr.c:505
vfs_removexattr+0x7d/0x1b0 fs/xattr.c:527
removexattr fs/xattr.c:857 [inline]
path_removexattr+0x1c9/0x3b0 fs/xattr.c:871
__do_sys_lremovexattr fs/xattr.c:891 [inline]
__se_sys_lremovexattr fs/xattr.c:888 [inline]
__x64_sys_lremovexattr+0x59/0x70 fs/xattr.c:888
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 (&oi->ip_xattr_sem){++++}-{3:3}:
down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498
ocfs2_init_acl+0x2fb/0x720 fs/ocfs2/acl.c:365
ocfs2_mknod+0x142f/0x22b0 fs/ocfs2/namei.c:410
ocfs2_create+0x192/0x410 fs/ocfs2/namei.c:674
lookup_open fs/namei.c:3470 [inline]
open_last_lookups fs/namei.c:3540 [inline]
path_openat+0x11e1/0x2f30 fs/namei.c:3747
do_filp_open+0x1b3/0x3e0 fs/namei.c:3777
do_sys_openat2+0x142/0x4a0 fs/open.c:1253
do_sys_open fs/open.c:1269 [inline]
__do_sys_openat fs/open.c:1285 [inline]
__se_sys_openat fs/open.c:1280 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1280
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 (jbd2_handle){++++}-{0:0}:
start_this_handle+0x1338/0x15a0 fs/jbd2/transaction.c:464
jbd2__journal_start+0x2b7/0x5a0 fs/jbd2/transaction.c:521
jbd2_journal_start+0x26/0x30 fs/jbd2/transaction.c:560
ocfs2_start_trans+0x374/0x6c0 fs/ocfs2/journal.c:376
ocfs2_mknod+0xe2f/0x22b0 fs/ocfs2/namei.c:361
ocfs2_create+0x192/0x410 fs/ocfs2/namei.c:674
lookup_open fs/namei.c:3470 [inline]
open_last_lookups fs/namei.c:3540 [inline]
path_openat+0x11e1/0x2f30 fs/namei.c:3747
do_filp_open+0x1b3/0x3e0 fs/namei.c:3777
do_sys_openat2+0x142/0x4a0 fs/open.c:1253
do_sys_open fs/open.c:1269 [inline]
__do_sys_openat fs/open.c:1285 [inline]
__se_sys_openat fs/open.c:1280 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1280
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 (&journal->j_trans_barrier){.+.+}-{3:3}:
down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498
ocfs2_start_trans+0x368/0x6c0 fs/ocfs2/journal.c:374
ocfs2_mknod+0xe2f/0x22b0 fs/ocfs2/namei.c:361
ocfs2_create+0x192/0x410 fs/ocfs2/namei.c:674
lookup_open fs/namei.c:3470 [inline]
open_last_lookups fs/namei.c:3540 [inline]
path_openat+0x11e1/0x2f30 fs/namei.c:3747
do_filp_open+0x1b3/0x3e0 fs/namei.c:3777
do_sys_openat2+0x142/0x4a0 fs/open.c:1253
do_sys_open fs/open.c:1269 [inline]
__do_sys_openat fs/open.c:1285 [inline]
__se_sys_openat fs/open.c:1280 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1280
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 (sb_internal#2){.+.+}-{0:0}:
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
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write include/linux/fs.h:1811 [inline]
sb_start_intwrite include/linux/fs.h:1928 [inline]
ocfs2_start_trans+0x269/0x6c0 fs/ocfs2/journal.c:372
ocfs2_write_begin_inline fs/ocfs2/aops.c:1482 [inline]
ocfs2_try_to_write_inline_data fs/ocfs2/aops.c:1585 [inline]
ocfs2_write_begin_nolock+0x1c5e/0x4180 fs/ocfs2/aops.c:1671
ocfs2_write_begin+0x1ab/0x300 fs/ocfs2/aops.c:1905
generic_perform_write+0x2aa/0x530 mm/filemap.c:3785
__generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912
ocfs2_file_write_iter+0x1578/0x1cf0 fs/ocfs2/file.c:2472
call_write_iter include/linux/fs.h:2173 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x712/0xd00 fs/read_write.c:594
ksys_write+0x14d/0x250 fs/read_write.c:647
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:
sb_internal#2 --> &oi->ip_xattr_sem --> &oi->ip_alloc_sem

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&oi->ip_alloc_sem);
lock(&oi->ip_xattr_sem);
lock(&oi->ip_alloc_sem);
lock(sb_internal#2);

*** DEADLOCK ***

3 locks held by syz.0.17/4317:
#0: ffff88807d768460 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x28a/0xd00 fs/read_write.c:590
#1: ffff88805d1e42c8 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
#1: ffff88805d1e42c8 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ocfs2_file_write_iter+0x401/0x1cf0 fs/ocfs2/file.c:2402
#2: ffff88805d1e3f60 (&oi->ip_alloc_sem){++++}-{3:3}, at: ocfs2_write_begin+0x18a/0x300 fs/ocfs2/aops.c:1903

stack backtrace:
CPU: 0 PID: 4317 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write include/linux/fs.h:1811 [inline]
sb_start_intwrite include/linux/fs.h:1928 [inline]
ocfs2_start_trans+0x269/0x6c0 fs/ocfs2/journal.c:372
ocfs2_write_begin_inline fs/ocfs2/aops.c:1482 [inline]
ocfs2_try_to_write_inline_data fs/ocfs2/aops.c:1585 [inline]
ocfs2_write_begin_nolock+0x1c5e/0x4180 fs/ocfs2/aops.c:1671
ocfs2_write_begin+0x1ab/0x300 fs/ocfs2/aops.c:1905
generic_perform_write+0x2aa/0x530 mm/filemap.c:3785
__generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912
ocfs2_file_write_iter+0x1578/0x1cf0 fs/ocfs2/file.c:2472
call_write_iter include/linux/fs.h:2173 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x712/0xd00 fs/read_write.c:594
ksys_write+0x14d/0x250 fs/read_write.c:647
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: 0033:0x7f2b95b96749
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:00007ffd20bd19c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f2b95decfa0 RCX: 00007f2b95b96749
RDX: 0000000000000050 RSI: 0000200000000440 RDI: 0000000000000004
RBP: 00007f2b95c1af91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2b95decfa0 R14: 00007f2b95decfa0 R15: 0000000000000003
</TASK>


---
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