[syzbot] [ocfs2?] possible deadlock in ocfs2_xattr_get (2)
From: syzbot
Date: Thu Aug 27 2026 - 15:48:33 EST
Hello,
syzbot found the following issue on:
HEAD commit: 73e3f0710014 Merge tag 'nfs-for-7.3-1' of git://git.linux-..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=136a3579580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9efed59cf70d6280
dashboard link: https://syzkaller.appspot.com/bug?extid=c63f5bc973ab97368c21
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ffcd3fee974f/disk-73e3f071.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/cf4f954d6b1a/vmlinux-73e3f071.xz
kernel image: https://storage.googleapis.com/syzbot-assets/45faed1d28b1/bzImage-73e3f071.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c63f5bc973ab97368c21@xxxxxxxxxxxxxxxxxxxxxxxxx
ocfs2: Slot 0 on device (7,9) was already allocated to this node!
JBD2: Ignoring recovery information on journal
ocfs2: Mounting device (7,9) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.9.729/14532 is trying to acquire lock:
ffff888062520858 (&oi->ip_xattr_sem){++++}-{4:4}, at: ocfs2_xattr_get+0xf4/0x260 fs/ocfs2/xattr.c:1578
but task is already holding lock:
ffff88803357f118 (&journal->j_trans_barrier){.+.+}-{4:4}, at: ocfs2_start_trans+0x3af/0x700 fs/ocfs2/journal.c:369
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (&journal->j_trans_barrier){.+.+}-{4:4}:
down_read+0x97/0x200 kernel/locking/rwsem.c:1574
ocfs2_start_trans+0x3af/0x700 fs/ocfs2/journal.c:369
ocfs2_block_group_alloc fs/ocfs2/suballoc.c:801 [inline]
ocfs2_reserve_suballoc_bits+0x7b7/0x4850 fs/ocfs2/suballoc.c:950
ocfs2_reserve_new_metadata_blocks+0x415/0x9a0 fs/ocfs2/suballoc.c:1100
ocfs2_expand_inline_dir fs/ocfs2/dir.c:2928 [inline]
ocfs2_extend_dir+0xd35/0x4b60 fs/ocfs2/dir.c:3290
ocfs2_prepare_dir_for_insert+0x339a/0x5190 fs/ocfs2/dir.c:4408
ocfs2_mknod+0x86f/0x22b0 fs/ocfs2/namei.c:299
ocfs2_mkdir+0x180/0x430 fs/ocfs2/namei.c:667
vfs_mkdir+0x408/0x620 fs/namei.c:5410
filename_mkdirat+0x289/0x520 fs/namei.c:5443
__do_sys_mkdirat fs/namei.c:5464 [inline]
__se_sys_mkdirat+0x35/0x150 fs/namei.c:5461
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #2 (sb_internal#7){.+.+}-{0:0}:
percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
__sb_start_write include/linux/fs/super.h:19 [inline]
sb_start_intwrite include/linux/fs/super.h:177 [inline]
ocfs2_start_trans+0x2ac/0x700 fs/ocfs2/journal.c:367
ocfs2_orphan_for_truncate fs/ocfs2/file.c:397 [inline]
ocfs2_truncate_file+0x634/0x14b0 fs/ocfs2/file.c:506
ocfs2_setattr+0x1641/0x1d10 fs/ocfs2/file.c:1224
notify_change+0xbb8/0xec0 fs/attr.c:556
do_truncate+0x1c2/0x250 fs/open.c:68
handle_truncate fs/namei.c:4300 [inline]
do_open fs/namei.c:4841 [inline]
path_openat+0x15ba/0x1d60 fs/namei.c:5000
do_file_open+0x23e/0x4a0 fs/namei.c:5029
do_sys_openat2+0x115/0x200 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_openat fs/open.c:1439 [inline]
__se_sys_openat fs/open.c:1434 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1434
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #1 (&ocfs2_file_ip_alloc_sem_key){++++}-{4:4}:
down_write+0x3a/0x50 kernel/locking/rwsem.c:1631
ocfs2_try_remove_refcount_tree+0xb6/0x360 fs/ocfs2/refcounttree.c:959
ocfs2_truncate_file+0xe91/0x14b0 fs/ocfs2/file.c:527
ocfs2_setattr+0x1641/0x1d10 fs/ocfs2/file.c:1224
notify_change+0xbb8/0xec0 fs/attr.c:556
do_truncate+0x1c2/0x250 fs/open.c:68
handle_truncate fs/namei.c:4300 [inline]
do_open fs/namei.c:4841 [inline]
path_openat+0x15ba/0x1d60 fs/namei.c:5000
do_file_open+0x23e/0x4a0 fs/namei.c:5029
do_sys_openat2+0x115/0x200 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_openat fs/open.c:1439 [inline]
__se_sys_openat fs/open.c:1434 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1434
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (&oi->ip_xattr_sem){++++}-{4:4}:
check_prev_add kernel/locking/lockdep.c:3181 [inline]
check_prevs_add kernel/locking/lockdep.c:3300 [inline]
validate_chain kernel/locking/lockdep.c:3924 [inline]
__lock_acquire+0x1520/0x2ce0 kernel/locking/lockdep.c:5253
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5886
down_read+0x97/0x200 kernel/locking/rwsem.c:1574
ocfs2_xattr_get+0xf4/0x260 fs/ocfs2/xattr.c:1578
__vfs_getxattr+0x412/0x440 fs/xattr.c:446
smk_fetch+0xb4/0x140 security/smack/smack_lsm.c:298
smack_d_instantiate+0x757/0x990 security/smack/smack_lsm.c:3679
security_d_instantiate+0x106/0x1d0 security/security.c:3703
d_instantiate+0x54/0xb0 fs/dcache.c:2176
ocfs2_mknod+0x1acb/0x22b0 fs/ocfs2/namei.c:459
ocfs2_mkdir+0x180/0x430 fs/ocfs2/namei.c:667
vfs_mkdir+0x408/0x620 fs/namei.c:5410
filename_mkdirat+0x289/0x520 fs/namei.c:5443
__do_sys_mkdirat fs/namei.c:5464 [inline]
__se_sys_mkdirat+0x35/0x150 fs/namei.c:5461
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
other info that might help us debug this:
Chain exists of:
&oi->ip_xattr_sem --> sb_internal#7 --> &journal->j_trans_barrier
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
rlock(&journal->j_trans_barrier);
lock(sb_internal#7);
lock(&journal->j_trans_barrier);
rlock(&oi->ip_xattr_sem);
*** DEADLOCK ***
locks held by syz.9.729/14532: 8, last CPU#0:
#0: ffff888063998510 (sb_writers#34){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494
#1: ffff88806243f000 (&type->i_mutex_dir_key#24/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1070 [inline]
#1: ffff88806243f000 (&type->i_mutex_dir_key#24/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline]
#1: ffff88806243f000 (&type->i_mutex_dir_key#24/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline]
#1: ffff88806243f000 (&type->i_mutex_dir_key#24/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:5092
#2: ffff888056ebbdc0 (&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1025 [inline]
#2: ffff888056ebbdc0 (&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_reserve_suballoc_bits+0x170/0x4850 fs/ocfs2/suballoc.c:904
#3: ffff888056ebce80 (&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1025 [inline]
#3: ffff888056ebce80 (&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_reserve_suballoc_bits+0x170/0x4850 fs/ocfs2/suballoc.c:904
#4: ffff888056eb8b80 (&ocfs2_sysfile_lock_key[LOCAL_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1025 [inline]
#4: ffff888056eb8b80 (&ocfs2_sysfile_lock_key[LOCAL_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_reserve_local_alloc_bits+0x11f/0x2680 fs/ocfs2/localalloc.c:636
#5: ffff888063998800 (sb_internal#7){.+.+}-{0:0}, at: ocfs2_mknod+0xf72/0x22b0 fs/ocfs2/namei.c:370
#6: ffff88803357f118 (&journal->j_trans_barrier){.+.+}-{4:4}, at: ocfs2_start_trans+0x3af/0x700 fs/ocfs2/journal.c:369
#7: ffff888028f16bb0 (jbd2_handle#2){.+.+}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444
stack backtrace:
CPU: 0 UID: 0 PID: 14532 Comm: syz.9.729 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2059
check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2191
check_prev_add kernel/locking/lockdep.c:3181 [inline]
check_prevs_add kernel/locking/lockdep.c:3300 [inline]
validate_chain kernel/locking/lockdep.c:3924 [inline]
__lock_acquire+0x1520/0x2ce0 kernel/locking/lockdep.c:5253
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5886
down_read+0x97/0x200 kernel/locking/rwsem.c:1574
ocfs2_xattr_get+0xf4/0x260 fs/ocfs2/xattr.c:1578
__vfs_getxattr+0x412/0x440 fs/xattr.c:446
smk_fetch+0xb4/0x140 security/smack/smack_lsm.c:298
smack_d_instantiate+0x757/0x990 security/smack/smack_lsm.c:3679
security_d_instantiate+0x106/0x1d0 security/security.c:3703
d_instantiate+0x54/0xb0 fs/dcache.c:2176
ocfs2_mknod+0x1acb/0x22b0 fs/ocfs2/namei.c:459
ocfs2_mkdir+0x180/0x430 fs/ocfs2/namei.c:667
vfs_mkdir+0x408/0x620 fs/namei.c:5410
filename_mkdirat+0x289/0x520 fs/namei.c:5443
__do_sys_mkdirat fs/namei.c:5464 [inline]
__se_sys_mkdirat+0x35/0x150 fs/namei.c:5461
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f98c067cf47
Code: 00 66 90 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 db f7 ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 b8 02 01 00 00 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:00007f98be8d5e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f98be8d5ee0 RCX: 00007f98c067cf47
RDX: 00000000000001ff RSI: 00002000000001c0 RDI: 00000000ffffff9c
RBP: 0000200000000040 R08: 0000200000000240 R09: 0000000000000000
R10: 0000200000000040 R11: 0000000000000246 R12: 00002000000001c0
R13: 00007f98be8d5ea0 R14: 0000000000000000 R15: 0000000000000000
</TASK>
gadgetfs: bound to dummy_udc driver
---
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