[v6.1] possible deadlock in ocfs2_truncate_file

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syzbot

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Dec 1, 2024, 12:06:26 AM12/1/24

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Hello,

syzbot found the following issue on:

HEAD commit: e4d90d63d385 Linux 6.1.119
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=17fa40df980000
kernel config: https://syzkaller.appspot.com/x/.config?x=393f8074c5fb7ad6
dashboard link: https://syzkaller.appspot.com/bug?extid=3597623c9c1c862c69ec
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/3986cbf4f35a/disk-e4d90d63.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d2963d16cebb/vmlinux-e4d90d63.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a877a1a23701/Image-e4d90d63.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+359762...@syzkaller.appspotmail.com

ocfs2: Mounting device (7,5) on (node local, slot 0) with writeback data mode.
======================================================
WARNING: possible circular locking dependency detected
6.1.119-syzkaller #0 Not tainted
------------------------------------------------------
syz.5.669/7351 is trying to acquire lock:
ffff0000d99ee650 (sb_internal#3){.+.+}-{0:0}, at: ocfs2_orphan_for_truncate fs/ocfs2/file.c:392 [inline]
ffff0000d99ee650 (sb_internal#3){.+.+}-{0:0}, at: ocfs2_truncate_file+0x640/0x1618 fs/ocfs2/file.c:496

but task is already holding lock:
ffff0000e15d22e0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_truncate_file+0x38c/0x1618 fs/ocfs2/file.c:467

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}:
down_write+0x5c/0x88 kernel/locking/rwsem.c:1573
ocfs2_try_remove_refcount_tree+0xb4/0x2f0 fs/ocfs2/refcounttree.c:932
ocfs2_xattr_set+0x7b8/0x1478 fs/ocfs2/xattr.c:3673
ocfs2_set_acl+0x410/0x4b4 fs/ocfs2/acl.c:254
ocfs2_iop_set_acl+0x214/0x358 fs/ocfs2/acl.c:285
set_posix_acl fs/posix_acl.c:1160 [inline]
posix_acl_xattr_set+0x2f8/0x398 fs/posix_acl.c:1189
__vfs_removexattr+0x370/0x38c fs/xattr.c:479
__vfs_removexattr_locked+0x1d8/0x380 fs/xattr.c:514
vfs_removexattr+0xe0/0x23c fs/xattr.c:536
removexattr fs/xattr.c:878 [inline]
path_removexattr+0x1ec/0x2ec fs/xattr.c:892
__do_sys_removexattr fs/xattr.c:906 [inline]
__se_sys_removexattr fs/xattr.c:903 [inline]
__arm64_sys_removexattr+0x60/0x78 fs/xattr.c:903
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

-> #3 (&oi->ip_xattr_sem){++++}-{3:3}:
down_read+0x64/0x308 kernel/locking/rwsem.c:1520
ocfs2_init_acl+0x2c8/0x764 fs/ocfs2/acl.c:365
ocfs2_mknod+0x1574/0x2560 fs/ocfs2/namei.c:408
ocfs2_create+0x1a8/0x560 fs/ocfs2/namei.c:672
lookup_open fs/namei.c:3482 [inline]
open_last_lookups fs/namei.c:3550 [inline]
path_openat+0xeac/0x2548 fs/namei.c:3780
do_filp_open+0x1bc/0x3cc fs/namei.c:3810
do_sys_openat2+0x128/0x3e0 fs/open.c:1318
do_sys_open fs/open.c:1334 [inline]
__do_sys_openat fs/open.c:1350 [inline]
__se_sys_openat fs/open.c:1345 [inline]
__arm64_sys_openat+0x1f0/0x240 fs/open.c:1345
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

-> #2 (jbd2_handle){++++}-{0:0}:
start_this_handle+0x1140/0x13ac fs/jbd2/transaction.c:463
jbd2__journal_start+0x298/0x544 fs/jbd2/transaction.c:520
jbd2_journal_start+0x3c/0x4c fs/jbd2/transaction.c:559
ocfs2_start_trans+0x3e8/0x73c fs/ocfs2/journal.c:354
ocfs2_shutdown_local_alloc+0x1d8/0x8d8 fs/ocfs2/localalloc.c:416
ocfs2_dismount_volume+0x1fc/0x99c fs/ocfs2/super.c:1879
ocfs2_put_super+0x110/0x3e8 fs/ocfs2/super.c:1609
generic_shutdown_super+0x130/0x328 fs/super.c:501
kill_block_super+0x70/0xdc fs/super.c:1470
deactivate_locked_super+0xac/0x124 fs/super.c:332
deactivate_super+0xf0/0x110 fs/super.c:363
cleanup_mnt+0x394/0x41c fs/namespace.c:1186
__cleanup_mnt+0x20/0x30 fs/namespace.c:1193
task_work_run+0x240/0x2f0 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
do_notify_resume+0x2080/0x2cb8 arch/arm64/kernel/signal.c:1132
prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
el0_svc+0x9c/0x168 arch/arm64/kernel/entry-common.c:638
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

-> #1 (&journal->j_trans_barrier){.+.+}-{3:3}:
down_read+0x64/0x308 kernel/locking/rwsem.c:1520
ocfs2_start_trans+0x3dc/0x73c fs/ocfs2/journal.c:352
ocfs2_shutdown_local_alloc+0x1d8/0x8d8 fs/ocfs2/localalloc.c:416
ocfs2_dismount_volume+0x1fc/0x99c fs/ocfs2/super.c:1879
ocfs2_put_super+0x110/0x3e8 fs/ocfs2/super.c:1609
generic_shutdown_super+0x130/0x328 fs/super.c:501
kill_block_super+0x70/0xdc fs/super.c:1470
deactivate_locked_super+0xac/0x124 fs/super.c:332
deactivate_super+0xf0/0x110 fs/super.c:363
cleanup_mnt+0x394/0x41c fs/namespace.c:1186
__cleanup_mnt+0x20/0x30 fs/namespace.c:1193
task_work_run+0x240/0x2f0 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
do_notify_resume+0x2080/0x2cb8 arch/arm64/kernel/signal.c:1132
prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
el0_svc+0x9c/0x168 arch/arm64/kernel/entry-common.c:638
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

-> #0 (sb_internal#3){.+.+}-{0:0}:
check_prev_add kernel/locking/lockdep.c:3090 [inline]
check_prevs_add kernel/locking/lockdep.c:3209 [inline]
validate_chain kernel/locking/lockdep.c:3825 [inline]
__lock_acquire+0x3338/0x7680 kernel/locking/lockdep.c:5049
lock_acquire+0x26c/0x7cc 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+0x260/0x73c fs/ocfs2/journal.c:350
ocfs2_orphan_for_truncate fs/ocfs2/file.c:392 [inline]
ocfs2_truncate_file+0x640/0x1618 fs/ocfs2/file.c:496
ocfs2_setattr+0x142c/0x1b5c fs/ocfs2/file.c:1212
notify_change+0xb58/0xe1c fs/attr.c:499
do_truncate+0x1c0/0x28c fs/open.c:65
handle_truncate fs/namei.c:3285 [inline]
do_open fs/namei.c:3630 [inline]
path_openat+0x1fa0/0x2548 fs/namei.c:3783
do_filp_open+0x1bc/0x3cc fs/namei.c:3810
do_sys_openat2+0x128/0x3e0 fs/open.c:1318
do_sys_open fs/open.c:1334 [inline]
__do_sys_openat fs/open.c:1350 [inline]
__se_sys_openat fs/open.c:1345 [inline]
__arm64_sys_openat+0x1f0/0x240 fs/open.c:1345
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

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.5.669/7351:
#0: ffff0000d99ee460 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
#1: ffff0000e15d2648 (&sb->s_type->i_mutex_key#40){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
#1: ffff0000e15d2648 (&sb->s_type->i_mutex_key#40){+.+.}-{3:3}, at: do_truncate+0x1ac/0x28c fs/open.c:63
#2: ffff0000e15d22e0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_truncate_file+0x38c/0x1618 fs/ocfs2/file.c:467

stack backtrace:
CPU: 0 PID: 7351 Comm: syz.5.669 Not tainted 6.1.119-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call trace:
dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
__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:2048
check_noncircular+0x2cc/0x378 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 kernel/locking/lockdep.c:3825 [inline]
__lock_acquire+0x3338/0x7680 kernel/locking/lockdep.c:5049
lock_acquire+0x26c/0x7cc 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+0x260/0x73c fs/ocfs2/journal.c:350
ocfs2_orphan_for_truncate fs/ocfs2/file.c:392 [inline]
ocfs2_truncate_file+0x640/0x1618 fs/ocfs2/file.c:496
ocfs2_setattr+0x142c/0x1b5c fs/ocfs2/file.c:1212
notify_change+0xb58/0xe1c fs/attr.c:499
do_truncate+0x1c0/0x28c fs/open.c:65
handle_truncate fs/namei.c:3285 [inline]
do_open fs/namei.c:3630 [inline]
path_openat+0x1fa0/0x2548 fs/namei.c:3783
do_filp_open+0x1bc/0x3cc fs/namei.c:3810
do_sys_openat2+0x128/0x3e0 fs/open.c:1318
do_sys_open fs/open.c:1334 [inline]
__do_sys_openat fs/open.c:1350 [inline]
__se_sys_openat fs/open.c:1345 [inline]
__arm64_sys_openat+0x1f0/0x240 fs/open.c:1345
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

---
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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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(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
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If you want to undo deduplication, reply with:
#syz undup

syzbot

unread,

Mar 1, 2025, 4:01:28 AM3/1/25

to syzkaller...@googlegroups.com

syzbot has found a reproducer for the following issue on:

HEAD commit: 3a8358583626 Linux 6.1.129
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1528c864580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ff93ecc085d8436e

dashboard link: https://syzkaller.appspot.com/bug?extid=3597623c9c1c862c69ec
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=163ec5a8580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15ecc8b7980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3cc3985223b7/disk-3a835858.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e40398fb298b/vmlinux-3a835858.xz
kernel image: https://storage.googleapis.com/syzbot-assets/40469708dc9a/Image-3a835858.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/9dd85e713651/mount_0.gz
fsck result: OK (log: https://syzkaller.appspot.com/x/fsck.log?x=1506d7b8580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+359762...@syzkaller.appspotmail.com

ocfs2: Slot 0 on device (7,0) was already allocated to this node!
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.

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

6.1.129-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor246/4289 is trying to acquire lock:
ffff0000de81e650 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_orphan_for_truncate fs/ocfs2/file.c:392 [inline]
ffff0000de81e650 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_truncate_file+0x640/0x1618 fs/ocfs2/file.c:496

but task is already holding lock:

ffff0000e16d0660 (&oi->ip_alloc_sem){++++}-{3:3}, at: ocfs2_truncate_file+0x38c/0x1618 fs/ocfs2/file.c:467

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #3 (&oi->ip_alloc_sem){++++}-{3:3}:
down_read+0x64/0x308 kernel/locking/rwsem.c:1520
ocfs2_read_virt_blocks+0x2bc/0x9f8 fs/ocfs2/extent_map.c:976
ocfs2_read_dir_block fs/ocfs2/dir.c:508 [inline]
ocfs2_find_entry_el fs/ocfs2/dir.c:715 [inline]
ocfs2_find_entry+0x3d0/0x23c4 fs/ocfs2/dir.c:1091
ocfs2_rename+0x1cb4/0x3588 fs/ocfs2/namei.c:1568
vfs_rename+0xac8/0xe04 fs/namei.c:4874
do_renameat2+0x9ec/0xe64 fs/namei.c:5027
__do_sys_renameat2 fs/namei.c:5060 [inline]
__se_sys_renameat2 fs/namei.c:5057 [inline]
__arm64_sys_renameat2+0xe0/0xfc fs/namei.c:5057

__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

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

start_this_handle+0x1140/0x13ac fs/jbd2/transaction.c:463
jbd2__journal_start+0x298/0x544 fs/jbd2/transaction.c:520
jbd2_journal_start+0x3c/0x4c fs/jbd2/transaction.c:559
ocfs2_start_trans+0x3e8/0x73c fs/ocfs2/journal.c:354

ocfs2_local_alloc_slide_window fs/ocfs2/localalloc.c:1258 [inline]
ocfs2_reserve_local_alloc_bits+0x9b4/0x2610 fs/ocfs2/localalloc.c:668
ocfs2_reserve_clusters_with_limit+0x194/0xabc fs/ocfs2/suballoc.c:1162
ocfs2_reserve_clusters+0x3c/0x50 fs/ocfs2/suballoc.c:1223
ocfs2_mknod+0xe04/0x2560 fs/ocfs2/namei.c:354
ocfs2_mkdir+0x1a8/0x560 fs/ocfs2/namei.c:657
vfs_mkdir+0x334/0x4e4 fs/namei.c:4106
do_mkdirat+0x220/0x510 fs/namei.c:4131
__do_sys_mkdirat fs/namei.c:4146 [inline]
__se_sys_mkdirat fs/namei.c:4144 [inline]
__arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4144

-> #1 (&journal->j_trans_barrier){.+.+}-{3:3}:
down_read+0x64/0x308 kernel/locking/rwsem.c:1520
ocfs2_start_trans+0x3dc/0x73c fs/ocfs2/journal.c:352

-> #0 (sb_internal#2){.+.+}-{0:0}:

sb_internal#2 --> jbd2_handle --> &oi->ip_alloc_sem

Possible unsafe locking scenario:

CPU0 CPU1
---- ----

lock(&oi->ip_alloc_sem);
lock(jbd2_handle);
lock(&oi->ip_alloc_sem);
lock(sb_internal#2);

*** DEADLOCK ***

3 locks held by syz-executor246/4289:
#0: ffff0000de81e460 (sb_writers#8){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
#1: ffff0000e16d09c8 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
#1: ffff0000e16d09c8 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: do_truncate+0x1ac/0x28c fs/open.c:63
#2: ffff0000e16d0660 (&oi->ip_alloc_sem){++++}-{3:3}, at: ocfs2_truncate_file+0x38c/0x1618 fs/ocfs2/file.c:467

stack backtrace:
CPU: 1 PID: 4289 Comm: syz-executor246 Not tainted 6.1.129-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
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