syzbot has found a reproducer for the following issue on:
HEAD commit: 8a7f2a5c5aa1 Linux 5.15.110
git tree: linux-5.15.y
console output:
https://syzkaller.appspot.com/x/log.txt?x=1444e15c280000
kernel config:
https://syzkaller.appspot.com/x/.config?x=7e93d602da27af41
userspace arch: arm64
syz repro:
https://syzkaller.appspot.com/x/repro.syz?x=13105938280000
C reproducer:
https://syzkaller.appspot.com/x/repro.c?x=12741f04280000
Downloadable assets:
disk image:
https://storage.googleapis.com/syzbot-assets/16bea75b636d/disk-8a7f2a5c.raw.xz
vmlinux:
https://storage.googleapis.com/syzbot-assets/3b169e33dcf2/vmlinux-8a7f2a5c.xz
kernel image:
https://storage.googleapis.com/syzbot-assets/190d08a00950/Image-8a7f2a5c.gz.xz
mounted in repro:
https://storage.googleapis.com/syzbot-assets/3add93d61bde/mount_0.gz
REISERFS (device loop0): using 3.5.x disk format
REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.
======================================================
WARNING: possible circular locking dependency detected
5.15.110-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor865/3961 is trying to acquire lock:
ffff0000c887e460 (sb_writers#8){.+.+}-{0:0}, at: mnt_want_write_file+0x64/0x1e8 fs/namespace.c:421
but task is already holding lock:
ffff0000c1ec6090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&sbi->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
reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
reiserfs_lookup+0x130/0x3c4 fs/reiserfs/namei.c:364
__lookup_slow+0x250/0x388 fs/namei.c:1659
lookup_one_len+0x178/0x28c fs/namei.c:2688
reiserfs_lookup_privroot+0x8c/0x204 fs/reiserfs/xattr.c:980
reiserfs_fill_super+0x1aec/0x1e8c fs/reiserfs/super.c:2178
mount_bdev+0x26c/0x368 fs/super.c:1378
get_super_block+0x44/0x58 fs/reiserfs/super.c:2608
legacy_get_tree+0xd4/0x16c fs/fs_context.c:610
vfs_get_tree+0x90/0x274 fs/super.c:1508
do_new_mount+0x25c/0x8c8 fs/namespace.c:2994
path_mount+0x590/0x104c fs/namespace.c:3324
do_mount fs/namespace.c:3337 [inline]
__do_sys_mount fs/namespace.c:3545 [inline]
__se_sys_mount fs/namespace.c:3522 [inline]
__arm64_sys_mount+0x510/0x5e0 fs/namespace.c:3522
__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:596
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
-> #1 (&type->i_mutex_dir_key#6){+.+.}-{3:3}:
down_write+0x110/0x260 kernel/locking/rwsem.c:1541
inode_lock include/linux/fs.h:787 [inline]
open_last_lookups fs/namei.c:3459 [inline]
path_openat+0x63c/0x26f0 fs/namei.c:3669
do_filp_open+0x1a8/0x3b4 fs/namei.c:3699
do_sys_openat2+0x128/0x3d8 fs/open.c:1211
do_sys_open fs/open.c:1227 [inline]
__do_sys_openat fs/open.c:1243 [inline]
__se_sys_openat fs/open.c:1238 [inline]
__arm64_sys_openat+0x1f0/0x240 fs/open.c:1238
__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:596
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
-> #0 (sb_writers#8){.+.+}-{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:3787 [inline]
__lock_acquire+0x32cc/0x7620 kernel/locking/lockdep.c:5011
lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5622
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write include/linux/fs.h:1742 [inline]
sb_start_write+0xf0/0x3ac include/linux/fs.h:1812
mnt_want_write_file+0x64/0x1e8 fs/namespace.c:421
reiserfs_ioctl+0x188/0x4b8 fs/reiserfs/ioctl.c:103
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl fs/ioctl.c:860 [inline]
__arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860
__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:596
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
other info that might help us debug this:
Chain exists of:
sb_writers#8 --> &type->i_mutex_dir_key#6 --> &sbi->lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&sbi->lock);
lock(&type->i_mutex_dir_key#6);
lock(&sbi->lock);
lock(sb_writers#8);
*** DEADLOCK ***
1 lock held by syz-executor865/3961:
#0: ffff0000c1ec6090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
stack backtrace:
CPU: 1 PID: 3961 Comm: syz-executor865 Not tainted 5.15.110-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
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:3787 [inline]
__lock_acquire+0x32cc/0x7620 kernel/locking/lockdep.c:5011
lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5622
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write include/linux/fs.h:1742 [inline]
sb_start_write+0xf0/0x3ac include/linux/fs.h:1812
mnt_want_write_file+0x64/0x1e8 fs/namespace.c:421
reiserfs_ioctl+0x188/0x4b8 fs/reiserfs/ioctl.c:103
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl fs/ioctl.c:860 [inline]
__arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860
__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:596
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
---
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