[v5.15] possible deadlock in ocfs2_write_info

5 views

Skip to first unread message

syzbot

unread,

Nov 10, 2024, 11:13:30 AM11/10/24

to syzkaller...@googlegroups.com

Hello,

syzbot found the following issue on:

HEAD commit: 3c17fc483905 Linux 5.15.171
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=17fae35f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=4ef7808b17b26971
dashboard link: https://syzkaller.appspot.com/bug?extid=a34bb4bd67ce2fbb7c35
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/46bed2db0d85/disk-3c17fc48.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7eb50004f2dc/vmlinux-3c17fc48.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c709f33dca6e/Image-3c17fc48.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a34bb4...@syzkaller.appspotmail.com

ocfs2: Mounting device (7,6) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
5.15.171-syzkaller #0 Not tainted
------------------------------------------------------
syz.6.662/7494 is trying to acquire lock:
ffff0000da104650 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_write_info+0x114/0x354 fs/ocfs2/quota_global.c:977

but task is already holding lock:
ffff0000ee0622e0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_lock_global_qf+0x1d4/0x260 fs/ocfs2/quota_global.c:314

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #6 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}:
down_write+0xbc/0x12c kernel/locking/rwsem.c:1551
ocfs2_lock_global_qf+0x1d4/0x260 fs/ocfs2/quota_global.c:314
ocfs2_acquire_dquot+0x258/0xa90 fs/ocfs2/quota_global.c:811
dqget+0x664/0xd0c fs/quota/dquot.c:986
ocfs2_setattr+0xc7c/0x191c fs/ocfs2/file.c:1243
notify_change+0xa34/0xcf8 fs/attr.c:505
chown_common+0x4ac/0x74c fs/open.c:680
vfs_fchown fs/open.c:748 [inline]
ksys_fchown+0xe0/0x158 fs/open.c:759
__do_sys_fchown fs/open.c:767 [inline]
__se_sys_fchown fs/open.c:765 [inline]
__arm64_sys_fchown+0x7c/0x94 fs/open.c:765
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #5 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{3:3}:
down_write+0xbc/0x12c kernel/locking/rwsem.c:1551
inode_lock include/linux/fs.h:789 [inline]
ocfs2_lock_global_qf+0x1b8/0x260 fs/ocfs2/quota_global.c:313
ocfs2_acquire_dquot+0x258/0xa90 fs/ocfs2/quota_global.c:811
dqget+0x664/0xd0c fs/quota/dquot.c:986
ocfs2_setattr+0xc7c/0x191c fs/ocfs2/file.c:1243
notify_change+0xa34/0xcf8 fs/attr.c:505
chown_common+0x4ac/0x74c fs/open.c:680
vfs_fchown fs/open.c:748 [inline]
ksys_fchown+0xe0/0x158 fs/open.c:759
__do_sys_fchown fs/open.c:767 [inline]
__se_sys_fchown fs/open.c:765 [inline]
__arm64_sys_fchown+0x7c/0x94 fs/open.c:765
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #4 (&dquot->dq_lock){+.+.}-{3:3}:
__mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
dquot_commit+0x54/0x240 fs/quota/dquot.c:507
ext4_write_dquot+0x1b4/0x314 fs/ext4/super.c:6173
ext4_mark_dquot_dirty+0xe8/0x140 fs/ext4/super.c:6233
mark_dquot_dirty fs/quota/dquot.c:372 [inline]
mark_all_dquot_dirty+0x108/0x424 fs/quota/dquot.c:412
__dquot_free_space+0x878/0xce8 fs/quota/dquot.c:1940
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:6156 [inline]
ext4_free_blocks+0x1bf8/0x2bdc fs/ext4/mballoc.c:6286
ext4_remove_blocks fs/ext4/extents.c:2523 [inline]
ext4_ext_rm_leaf fs/ext4/extents.c:2689 [inline]
ext4_ext_remove_space+0x1c48/0x4254 fs/ext4/extents.c:2937
ext4_ext_truncate+0x188/0x250 fs/ext4/extents.c:4471
ext4_truncate+0x9c4/0x1058 fs/ext4/inode.c:4249
ext4_process_orphan+0x180/0x2b8 fs/ext4/orphan.c:339
ext4_orphan_cleanup+0x8bc/0x1048 fs/ext4/orphan.c:474
ext4_fill_super+0x8044/0x8768 fs/ext4/super.c:4975
mount_bdev+0x274/0x370 fs/super.c:1400
ext4_mount+0x44/0x58 fs/ext4/super.c:6603
legacy_get_tree+0xd4/0x16c fs/fs_context.c:611
vfs_get_tree+0x90/0x274 fs/super.c:1530
do_new_mount+0x278/0x8fc fs/namespace.c:3012
path_mount+0x594/0x101c fs/namespace.c:3342
do_mount fs/namespace.c:3355 [inline]
__do_sys_mount fs/namespace.c:3563 [inline]
__se_sys_mount fs/namespace.c:3540 [inline]
__arm64_sys_mount+0x510/0x5e0 fs/namespace.c:3540
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #3 (&ei->i_data_sem){++++}-{3:3}:
down_write+0xbc/0x12c kernel/locking/rwsem.c:1551
ext4_map_blocks+0x830/0x1a44 fs/ext4/inode.c:665
mpage_map_one_extent fs/ext4/inode.c:2407 [inline]
mpage_map_and_submit_extent fs/ext4/inode.c:2460 [inline]
ext4_writepages+0x12c0/0x36fc fs/ext4/inode.c:2828
do_writepages+0x39c/0x5ec mm/page-writeback.c:2386
__writeback_single_inode+0x148/0x13a4 fs/fs-writeback.c:1647
writeback_sb_inodes+0x94c/0x1654 fs/fs-writeback.c:1930
__writeback_inodes_wb+0x110/0x39c fs/fs-writeback.c:2001
wb_writeback+0x410/0xfc8 fs/fs-writeback.c:2106
wb_check_background_flush fs/fs-writeback.c:2172 [inline]
wb_do_writeback fs/fs-writeback.c:2260 [inline]
wb_workfn+0xc44/0x1070 fs/fs-writeback.c:2288
process_one_work+0x790/0x11b8 kernel/workqueue.c:2310
worker_thread+0x910/0x1034 kernel/workqueue.c:2457
kthread+0x37c/0x45c kernel/kthread.c:334
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870

-> #2 (jbd2_handle){++++}-{0:0}:
start_this_handle+0xfc0/0x12a4 fs/jbd2/transaction.c:464
jbd2__journal_start+0x29c/0x7b4 fs/jbd2/transaction.c:521
jbd2_journal_start+0x3c/0x4c fs/jbd2/transaction.c:560
ocfs2_start_trans+0x468/0x804 fs/ocfs2/journal.c:354
ocfs2_mknod+0xe68/0x24f8 fs/ocfs2/namei.c:359
ocfs2_create+0x184/0x4c8 fs/ocfs2/namei.c:672
lookup_open fs/namei.c:3462 [inline]
open_last_lookups fs/namei.c:3532 [inline]
path_openat+0xf18/0x26cc fs/namei.c:3739
do_filp_open+0x1a8/0x3b4 fs/namei.c:3769
do_sys_openat2+0x128/0x3e0 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]
__arm64_sys_openat+0x1f0/0x240 fs/open.c:1280
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #1 (&journal->j_trans_barrier){.+.+}-{3:3}:
down_read+0xc0/0x398 kernel/locking/rwsem.c:1498
ocfs2_start_trans+0x45c/0x804 fs/ocfs2/journal.c:352
ocfs2_mknod+0xe68/0x24f8 fs/ocfs2/namei.c:359
ocfs2_create+0x184/0x4c8 fs/ocfs2/namei.c:672
lookup_open fs/namei.c:3462 [inline]
open_last_lookups fs/namei.c:3532 [inline]
path_openat+0xf18/0x26cc fs/namei.c:3739
do_filp_open+0x1a8/0x3b4 fs/namei.c:3769
do_sys_openat2+0x128/0x3e0 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]
__arm64_sys_openat+0x1f0/0x240 fs/open.c:1280
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #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+0x32d4/0x7638 kernel/locking/lockdep.c:5012
lock_acquire+0x240/0x77c 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+0x2dc/0x804 fs/ocfs2/journal.c:350
ocfs2_write_info+0x114/0x354 fs/ocfs2/quota_global.c:977
dquot_set_dqinfo+0x398/0x5f4 fs/quota/dquot.c:2902
quota_setinfo+0x3d8/0x524 fs/quota/quota.c:173
do_quotactl+0x4c0/0x698 fs/quota/quota.c:795
__do_sys_quotactl fs/quota/quota.c:959 [inline]
__se_sys_quotactl fs/quota/quota.c:915 [inline]
__arm64_sys_quotactl+0x2d8/0x7a4 fs/quota/quota.c:915
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

other info that might help us debug this:

Chain exists of:
sb_internal#2 --> &ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7 --> &ocfs2_quota_ip_alloc_sem_key

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&ocfs2_quota_ip_alloc_sem_key);
lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7);
lock(&ocfs2_quota_ip_alloc_sem_key);
lock(sb_internal#2);

*** DEADLOCK ***

3 locks held by syz.6.662/7494:
#0: ffff0000da1040e0 (&type->s_umount_key#51){++++}-{3:3}, at: user_get_super+0x11c/0x240 fs/super.c:850
#1: ffff0000ee062648 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline]
#1: ffff0000ee062648 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{3:3}, at: ocfs2_lock_global_qf+0x1b8/0x260 fs/ocfs2/quota_global.c:313
#2: ffff0000ee0622e0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_lock_global_qf+0x1d4/0x260 fs/ocfs2/quota_global.c:314

stack backtrace:
CPU: 1 PID: 7494 Comm: syz.6.662 Not tainted 5.15.171-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call trace:
dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
dump_stack+0x1c/0x58 lib/dump_stack.c:113
print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2011
check_noncircular+0x2cc/0x378 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+0x32d4/0x7638 kernel/locking/lockdep.c:5012
lock_acquire+0x240/0x77c 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+0x2dc/0x804 fs/ocfs2/journal.c:350
ocfs2_write_info+0x114/0x354 fs/ocfs2/quota_global.c:977
dquot_set_dqinfo+0x398/0x5f4 fs/quota/dquot.c:2902
quota_setinfo+0x3d8/0x524 fs/quota/quota.c:173
do_quotactl+0x4c0/0x698 fs/quota/quota.c:795
__do_sys_quotactl fs/quota/quota.c:959 [inline]
__se_sys_quotactl fs/quota/quota.c:915 [inline]
__arm64_sys_quotactl+0x2d8/0x7a4 fs/quota/quota.c:915
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

syzbot

unread,

Nov 13, 2024, 7:01:25 AM11/13/24

to syzkaller...@googlegroups.com

Hello,

syzbot found the following issue on:

HEAD commit: d7039b844a1c Linux 6.1.116
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14e4c1a7980000
kernel config: https://syzkaller.appspot.com/x/.config?x=a047880f6dd12cce
dashboard link: https://syzkaller.appspot.com/bug?extid=174454d7fe6c5c521bba

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/b531abf1deab/disk-d7039b84.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6780cfcf0543/vmlinux-d7039b84.xz
kernel image: https://storage.googleapis.com/syzbot-assets/398543175ad2/bzImage-d7039b84.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:

Reported-by: syzbot+174454...@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected

6.1.116-syzkaller #0 Not tainted
------------------------------------------------------
syz.0.7038/20571 is trying to acquire lock:
ffff88805817e650 (sb_internal#5){.+.+}-{0:0}, at: ocfs2_write_info+0x124/0x3a0 fs/ocfs2/quota_global.c:977

but task is already holding lock:

ffff88806aabdbe0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_lock_global_qf+0x221/0x2a0 fs/ocfs2/quota_global.c:314

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #6 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}
:

lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
down_write+0x36/0x60 kernel/locking/rwsem.c:1573
ocfs2_lock_global_qf+0x221/0x2a0 fs/ocfs2/quota_global.c:314
ocfs2_acquire_dquot+0x2ad/0xb60 fs/ocfs2/quota_global.c:811
dqget+0x762/0xe90 fs/quota/dquot.c:986
dquot_get_next_dqblk+0xb6/0x3a0 fs/quota/dquot.c:2718
quota_getnextquota+0x2bc/0x6b0 fs/quota/quota.c:250
__do_sys_quotactl fs/quota/quota.c:960 [inline]
__se_sys_quotactl+0x2b1/0x770 fs/quota/quota.c:916
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #5 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{3:3}
:

lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
down_write+0x36/0x60 kernel/locking/rwsem.c:1573
inode_lock include/linux/fs.h:758 [inline]
ocfs2_lock_global_qf+0x202/0x2a0 fs/ocfs2/quota_global.c:313
ocfs2_acquire_dquot+0x2ad/0xb60 fs/ocfs2/quota_global.c:811
dqget+0x762/0xe90 fs/quota/dquot.c:986
dquot_get_next_dqblk+0xb6/0x3a0 fs/quota/dquot.c:2718
quota_getnextquota+0x2bc/0x6b0 fs/quota/quota.c:250
__do_sys_quotactl fs/quota/quota.c:960 [inline]
__se_sys_quotactl+0x2b1/0x770 fs/quota/quota.c:916
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #4 (&dquot->dq_lock){+.+.}-{3:3}:

lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x132/0xd80 kernel/locking/mutex.c:747
dquot_commit+0x57/0x510 fs/quota/dquot.c:507
ext4_write_dquot+0x1fd/0x360 fs/ext4/super.c:6777
mark_dquot_dirty fs/quota/dquot.c:372 [inline]
mark_all_dquot_dirty+0xf7/0x400 fs/quota/dquot.c:412
__dquot_free_space+0x956/0xe70 fs/quota/dquot.c:1940
dquot_free_space_nodirty include/linux/quotaops.h:379 [inline]
dquot_free_space include/linux/quotaops.h:384 [inline]
dquot_free_block include/linux/quotaops.h:395 [inline]
ext4_mb_clear_bb fs/ext4/mballoc.c:6143 [inline]
ext4_free_blocks+0x1fb4/0x3020 fs/ext4/mballoc.c:6273
ext4_remove_blocks fs/ext4/extents.c:2525 [inline]
ext4_ext_rm_leaf fs/ext4/extents.c:2691 [inline]
ext4_ext_remove_space+0x22bb/0x4f30 fs/ext4/extents.c:2939
ext4_ext_truncate+0x201/0x360 fs/ext4/extents.c:4469
ext4_truncate+0xa1d/0x1290 fs/ext4/inode.c:4288
ext4_evict_inode+0xb68/0x1150 fs/ext4/inode.c:286
evict+0x529/0x930 fs/inode.c:701
do_unlinkat+0x509/0x820 fs/namei.c:4397
__do_sys_unlink fs/namei.c:4438 [inline]
__se_sys_unlink fs/namei.c:4436 [inline]
__x64_sys_unlink+0x45/0x50 fs/namei.c:4436
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #3 (&ei->i_data_sem){++++}-{3:3}:

lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
down_write+0x36/0x60 kernel/locking/rwsem.c:1573
ext4_truncate+0x999/0x1290 fs/ext4/inode.c:4283
ext4_setattr+0x10f5/0x1a00 fs/ext4/inode.c:5601
notify_change+0xce3/0xfc0 fs/attr.c:499
do_truncate+0x21c/0x300 fs/open.c:65
do_sys_ftruncate+0x2e2/0x380 fs/open.c:193
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #2 (jbd2_handle){++++}-{0:0}:

lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
start_this_handle+0x1f71/0x21b0 fs/jbd2/transaction.c:463
jbd2__journal_start+0x2d1/0x5c0 fs/jbd2/transaction.c:520
jbd2_journal_start+0x25/0x30 fs/jbd2/transaction.c:559
ocfs2_start_trans+0x3c0/0x6f0 fs/ocfs2/journal.c:354
ocfs2_shutdown_local_alloc+0x214/0xa90 fs/ocfs2/localalloc.c:416
ocfs2_dismount_volume+0x1fb/0x960 fs/ocfs2/super.c:1879
generic_shutdown_super+0x130/0x340 fs/super.c:501
kill_block_super+0x7a/0xe0 fs/super.c:1470
deactivate_locked_super+0xa0/0x110 fs/super.c:332
cleanup_mnt+0x490/0x520 fs/namespace.c:1186
task_work_run+0x246/0x300 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #1 (&journal->j_trans_barrier){.+.+}-{3:3}:

lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
down_read+0xad/0xa30 kernel/locking/rwsem.c:1520
ocfs2_start_trans+0x3b5/0x6f0 fs/ocfs2/journal.c:352
ocfs2_shutdown_local_alloc+0x214/0xa90 fs/ocfs2/localalloc.c:416
ocfs2_dismount_volume+0x1fb/0x960 fs/ocfs2/super.c:1879
generic_shutdown_super+0x130/0x340 fs/super.c:501
kill_block_super+0x7a/0xe0 fs/super.c:1470
deactivate_locked_super+0xa0/0x110 fs/super.c:332
cleanup_mnt+0x490/0x520 fs/namespace.c:1186
task_work_run+0x246/0x300 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (sb_internal#5){.+.+}-{0:0}:
check_prev_add kernel/locking/lockdep.c:3090 [inline]
check_prevs_add kernel/locking/lockdep.c:3209 [inline]
validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
__lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write include/linux/fs.h:1891 [inline]
sb_start_intwrite include/linux/fs.h:2013 [inline]
ocfs2_start_trans+0x2b0/0x6f0 fs/ocfs2/journal.c:350
ocfs2_write_info+0x124/0x3a0 fs/ocfs2/quota_global.c:977
dquot_set_dqinfo+0x488/0x6f0 fs/quota/dquot.c:2909
quota_setinfo+0x3d6/0x4f0 fs/quota/quota.c:174
__do_sys_quotactl fs/quota/quota.c:960 [inline]
__se_sys_quotactl+0x2b1/0x770 fs/quota/quota.c:916
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

Chain exists of:

sb_internal#5 --> &ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7 --> &ocfs2_quota_ip_alloc_sem_key

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&ocfs2_quota_ip_alloc_sem_key);
lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7);
lock(&ocfs2_quota_ip_alloc_sem_key);

lock(sb_internal#5);

*** DEADLOCK ***

3 locks held by syz.0.7038/20571:
#0: ffff88805817e0e0 (&type->s_umount_key#100){++++}-{3:3}, at: user_get_super+0x11a/0x250 fs/super.c:889
#1: ffff88806aabdf48 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
#1: ffff88806aabdf48 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{3:3}, at: ocfs2_lock_global_qf+0x202/0x2a0 fs/ocfs2/quota_global.c:313
#2: ffff88806aabdbe0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_lock_global_qf+0x221/0x2a0 fs/ocfs2/quota_global.c:314

stack backtrace:
CPU: 0 PID: 20571 Comm: syz.0.7038 Not tainted 6.1.116-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+0x1e3/0x2cb lib/dump_stack.c:106
check_noncircular+0x2fa/0x3b0 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+0x1661/0x5950 kernel/locking/lockdep.c:3825
__lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write include/linux/fs.h:1891 [inline]
sb_start_intwrite include/linux/fs.h:2013 [inline]
ocfs2_start_trans+0x2b0/0x6f0 fs/ocfs2/journal.c:350
ocfs2_write_info+0x124/0x3a0 fs/ocfs2/quota_global.c:977
dquot_set_dqinfo+0x488/0x6f0 fs/quota/dquot.c:2909
quota_setinfo+0x3d6/0x4f0 fs/quota/quota.c:174
__do_sys_quotactl fs/quota/quota.c:960 [inline]
__se_sys_quotactl+0x2b1/0x770 fs/quota/quota.c:916
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9d8e57e719
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:00007f9d8f2e9038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f9d8e735f80 RCX: 00007f9d8e57e719
RDX: 0000000000000000 RSI: 0000000020000380 RDI: ffffffff80000600
RBP: 00007f9d8e5f175e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f9d8e735f80 R15: 00007fff69d44788
</TASK>

syzbot

unread,

Jan 13, 2025, 6:40:26 PM1/13/25

to syzkaller...@googlegroups.com

syzbot has found a reproducer for the following issue on:

HEAD commit: 4735586da88e Linux 5.15.176
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=122f1bc4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=caf0c22a63c5c861

dashboard link: https://syzkaller.appspot.com/bug?extid=a34bb4bd67ce2fbb7c35
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=111c5cb0580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=151c5cb0580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3e7a2d136136/disk-4735586d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7597375cf469/vmlinux-4735586d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/132474c9ad82/Image-4735586d.gz.xz
mounted in repro #1: https://storage.googleapis.com/syzbot-assets/d0acc9127421/mount_0.gz
mounted in repro #2: https://storage.googleapis.com/syzbot-assets/4d8789810576/mount_2.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a34bb4...@syzkaller.appspotmail.com

(syz-executor168,4320,0):ocfs2_mknod:502 ERROR: status = -5
(syz-executor168,4320,0):ocfs2_create:676 ERROR: status = -5

======================================================
WARNING: possible circular locking dependency detected

5.15.176-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor168/4320 is trying to acquire lock:
ffff0000c7814650 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_write_info+0x114/0x354 fs/ocfs2/quota_global.c:977

but task is already holding lock:

ffff0000e1c3dbe0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_lock_global_qf+0x1d4/0x260 fs/ocfs2/quota_global.c:314

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #6 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}:
down_write+0xbc/0x12c kernel/locking/rwsem.c:1551
ocfs2_lock_global_qf+0x1d4/0x260 fs/ocfs2/quota_global.c:314
ocfs2_acquire_dquot+0x258/0xa90 fs/ocfs2/quota_global.c:811

dqget+0x664/0xd0c fs/quota/dquot.c:988
__dquot_initialize+0x344/0xc04 fs/quota/dquot.c:1517
dquot_initialize+0x24/0x34 fs/quota/dquot.c:1579
ocfs2_get_init_inode+0x14c/0x1c0 fs/ocfs2/namei.c:202
ocfs2_mknod+0x89c/0x24f8 fs/ocfs2/namei.c:310
ocfs2_create+0x184/0x4c8 fs/ocfs2/namei.c:674

lookup_open fs/namei.c:3462 [inline]
open_last_lookups fs/namei.c:3532 [inline]
path_openat+0xf18/0x26cc fs/namei.c:3739
do_filp_open+0x1a8/0x3b4 fs/namei.c:3769
do_sys_openat2+0x128/0x3e0 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]
__arm64_sys_openat+0x1f0/0x240 fs/open.c:1280
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #5 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}:

down_write+0xbc/0x12c kernel/locking/rwsem.c:1551
inode_lock include/linux/fs.h:789 [inline]
ocfs2_lock_global_qf+0x1b8/0x260 fs/ocfs2/quota_global.c:313
ocfs2_acquire_dquot+0x258/0xa90 fs/ocfs2/quota_global.c:811

-> #4 (&dquot->dq_lock){+.+.}-{3:3}:
__mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
dquot_commit+0x54/0x240 fs/quota/dquot.c:507
ext4_write_dquot+0x1b4/0x314 fs/ext4/super.c:6173
ext4_mark_dquot_dirty+0xe8/0x140 fs/ext4/super.c:6233
mark_dquot_dirty fs/quota/dquot.c:372 [inline]
mark_all_dquot_dirty+0x108/0x424 fs/quota/dquot.c:412

__dquot_free_space+0x878/0xce8 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:6156 [inline]
ext4_free_blocks+0x1bf8/0x2bdc fs/ext4/mballoc.c:6286

ext4_remove_blocks fs/ext4/extents.c:2505 [inline]
ext4_ext_rm_leaf fs/ext4/extents.c:2689 [inline]
ext4_ext_remove_space+0x1b54/0x4254 fs/ext4/extents.c:2937

ext4_ext_truncate+0x188/0x250 fs/ext4/extents.c:4471
ext4_truncate+0x9c4/0x1058 fs/ext4/inode.c:4249

ext4_setattr+0xc48/0x1440 fs/ext4/inode.c:5553
notify_change+0xa34/0xcf8 fs/attr.c:505
do_truncate+0x1c0/0x28c fs/open.c:65
vfs_truncate+0x2e0/0x388 fs/open.c:111
do_sys_truncate+0xec/0x1b4 fs/open.c:134
__do_sys_truncate fs/open.c:146 [inline]
__se_sys_truncate fs/open.c:144 [inline]
__arm64_sys_truncate+0x5c/0x70 fs/open.c:144

ocfs2_modify_bh+0xe4/0x498 fs/ocfs2/quota_local.c:101
ocfs2_local_read_info+0x1220/0x15bc fs/ocfs2/quota_local.c:768
dquot_load_quota_sb+0x6f0/0xb1c fs/quota/dquot.c:2463
dquot_load_quota_inode+0x280/0x4f4 fs/quota/dquot.c:2500
ocfs2_enable_quotas+0x17c/0x3cc fs/ocfs2/super.c:927
ocfs2_fill_super+0x37bc/0x4abc fs/ocfs2/super.c:1140
mount_bdev+0x274/0x370 fs/super.c:1400
ocfs2_mount+0x44/0x58 fs/ocfs2/super.c:1187

legacy_get_tree+0xd4/0x16c fs/fs_context.c:611
vfs_get_tree+0x90/0x274 fs/super.c:1530
do_new_mount+0x278/0x8fc fs/namespace.c:3012
path_mount+0x594/0x101c fs/namespace.c:3342
do_mount fs/namespace.c:3355 [inline]
__do_sys_mount fs/namespace.c:3563 [inline]
__se_sys_mount fs/namespace.c:3540 [inline]
__arm64_sys_mount+0x510/0x5e0 fs/namespace.c:3540
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #1 (&journal->j_trans_barrier){.+.+}-{3:3}:
down_read+0xc0/0x398 kernel/locking/rwsem.c:1498
ocfs2_start_trans+0x45c/0x804 fs/ocfs2/journal.c:352

-> #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+0x32d4/0x7638 kernel/locking/lockdep.c:5012
lock_acquire+0x240/0x77c 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+0x2dc/0x804 fs/ocfs2/journal.c:350
ocfs2_write_info+0x114/0x354 fs/ocfs2/quota_global.c:977

dquot_set_dqinfo+0x398/0x5f4 fs/quota/dquot.c:2904

quota_setinfo+0x3d8/0x524 fs/quota/quota.c:173
do_quotactl+0x4c0/0x698 fs/quota/quota.c:795
__do_sys_quotactl fs/quota/quota.c:959 [inline]
__se_sys_quotactl fs/quota/quota.c:915 [inline]
__arm64_sys_quotactl+0x2d8/0x7a4 fs/quota/quota.c:915
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

other info that might help us debug this:

Chain exists of:

sb_internal#2 --> &ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3 --> &ocfs2_quota_ip_alloc_sem_key

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&ocfs2_quota_ip_alloc_sem_key);

lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3);

lock(&ocfs2_quota_ip_alloc_sem_key);
lock(sb_internal#2);

*** DEADLOCK ***

3 locks held by syz-executor168/4320:
#0: ffff0000c78140e0 (&type->s_umount_key#41){.+.+}-{3:3}, at: user_get_super+0x11c/0x240 fs/super.c:850
#1: ffff0000e1c3df48 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline]
#1: ffff0000e1c3df48 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}, at: ocfs2_lock_global_qf+0x1b8/0x260 fs/ocfs2/quota_global.c:313
#2: ffff0000e1c3dbe0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_lock_global_qf+0x1d4/0x260 fs/ocfs2/quota_global.c:314

stack backtrace:
CPU: 0 PID: 4320 Comm: syz-executor168 Not tainted 5.15.176-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call trace:
dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
dump_stack+0x1c/0x58 lib/dump_stack.c:113
print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2011
check_noncircular+0x2cc/0x378 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+0x32d4/0x7638 kernel/locking/lockdep.c:5012
lock_acquire+0x240/0x77c 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+0x2dc/0x804 fs/ocfs2/journal.c:350
ocfs2_write_info+0x114/0x354 fs/ocfs2/quota_global.c:977

dquot_set_dqinfo+0x398/0x5f4 fs/quota/dquot.c:2904

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

Reply all

Reply to author

Forward

0 new messages