======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G L
------------------------------------------------------
syz.3.5400/4671 is trying to acquire lock:
ffff88802bf62668 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
but task is already holding lock:
ffff888056799468 (&pipe->mutex){+.+.}-{4:4}, at: pipe_lock fs/pipe.c:91 [inline]
ffff888056799468 (&pipe->mutex){+.+.}-{4:4}, at: pipe_lock+0x69/0x80 fs/pipe.c:88
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #4 (&pipe->mutex){+.+.}-{4:4}:
__mutex_lock_common kernel/locking/mutex.c:614 [inline]
__mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776
pipe_lock fs/pipe.c:91 [inline]
pipe_lock+0x69/0x80 fs/pipe.c:88
iter_file_splice_write+0x1fd/0x10a0 fs/splice.c:682
do_splice_from fs/splice.c:936 [inline]
do_splice+0x109c/0x1fd0 fs/splice.c:1349
__do_splice+0x237/0x370 fs/splice.c:1431
__do_sys_splice fs/splice.c:1634 [inline]
__se_sys_splice fs/splice.c:1616 [inline]
__x64_sys_splice+0x187/0x250 fs/splice.c:1616
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #3 (sb_writers#6){.+.+}-{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_write include/linux/fs/super.h:125 [inline]
mnt_want_write+0x6f/0x450 fs/namespace.c:493
ovl_create_object+0x12b/0x3b0 fs/overlayfs/dir.c:691
lookup_open.isra.0+0xc47/0x11b0 fs/namei.c:4483
open_last_lookups fs/namei.c:4583 [inline]
path_openat+0x2291/0x31a0 fs/namei.c:4827
do_file_open+0x20e/0x430 fs/namei.c:4859
do_sys_openat2+0x10d/0x1e0 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #2 (&ovl_i_mutex_dir_key[depth]#2){++++}-{4:4}:
down_read+0x99/0x460 kernel/locking/rwsem.c:1537
inode_lock_shared include/linux/fs.h:1043 [inline]
lookup_slow+0x42/0x70 fs/namei.c:1932
walk_component fs/namei.c:2279 [inline]
lookup_last fs/namei.c:2780 [inline]
path_lookupat+0x5e8/0xc40 fs/namei.c:2804
filename_lookup+0x202/0x590 fs/namei.c:2833
kern_path+0x37/0x50 fs/namei.c:3040
lookup_bdev+0xd8/0x280 block/bdev.c:1221
resume_store+0x1d6/0x460 kernel/power/hibernate.c:1306
kobj_attr_store+0x58/0x80 lib/kobject.c:840
sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:142
kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:352
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6ac/0x1070 fs/read_write.c:688
ksys_write+0x12a/0x250 fs/read_write.c:740
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #1 (&of->mutex){+.+.}-{4:4}:
__mutex_lock_common kernel/locking/mutex.c:614 [inline]
__mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776
kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
seq_read_iter+0x2c1/0x1270 fs/seq_file.c:226
kernfs_fop_read_iter+0x46c/0x610 fs/kernfs/file.c:297
copy_splice_read+0x4ba/0xb90 fs/splice.c:362
do_splice_read fs/splice.c:980 [inline]
do_splice_read+0x285/0x370 fs/splice.c:954
splice_direct_to_actor+0x2a1/0xa30 fs/splice.c:1084
do_splice_direct_actor fs/splice.c:1202 [inline]
do_splice_direct+0x174/0x240 fs/splice.c:1228
do_sendfile+0xadc/0xe20 fs/read_write.c:1372
__do_sys_sendfile64 fs/read_write.c:1433 [inline]
__se_sys_sendfile64 fs/read_write.c:1419 [inline]
__x64_sys_sendfile64+0x1d8/0x220 fs/read_write.c:1419
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (&p->lock){+.+.}-{4:4}:
check_prev_add kernel/locking/lockdep.c:3165 [inline]
check_prevs_add kernel/locking/lockdep.c:3284 [inline]
validate_chain kernel/locking/lockdep.c:3908 [inline]
__lock_acquire+0x14b8/0x2630 kernel/locking/lockdep.c:5237
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x1cf/0x380 kernel/locking/lockdep.c:5825
__mutex_lock_common kernel/locking/mutex.c:614 [inline]
__mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776
seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
proc_reg_read_iter+0x220/0x310 fs/proc/inode.c:299
copy_splice_read+0x4ba/0xb90 fs/splice.c:362
do_splice_read fs/splice.c:980 [inline]
do_splice_read+0x285/0x370 fs/splice.c:954
splice_file_to_pipe+0x82/0x120 fs/splice.c:1290
do_sendfile+0x366/0xe20 fs/read_write.c:1378
__do_sys_sendfile64 fs/read_write.c:1433 [inline]
__se_sys_sendfile64 fs/read_write.c:1419 [inline]
__x64_sys_sendfile64+0x1d8/0x220 fs/read_write.c:1419
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
other info that might help us debug this:
Chain exists of:
&p->lock --> sb_writers#6 --> &pipe->mutex
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&pipe->mutex);
lock(sb_writers#6);
lock(&pipe->mutex);
lock(&p->lock);
*** DEADLOCK ***
1 lock held by syz.3.5400/4671:
#0: ffff888056799468 (&pipe->mutex){+.+.}-{4:4}, at: pipe_lock fs/pipe.c:91 [inline]
#0: ffff888056799468 (&pipe->mutex){+.+.}-{4:4}, at: pipe_lock+0x69/0x80 fs/pipe.c:88
stack backtrace:
CPU: 1 UID: 0 PID: 4671 Comm: syz.3.5400 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_circular_bug.cold+0x178/0x1c7 kernel/locking/lockdep.c:2043
check_noncircular+0x146/0x160 kernel/locking/lockdep.c:2175
check_prev_add kernel/locking/lockdep.c:3165 [inline]
check_prevs_add kernel/locking/lockdep.c:3284 [inline]
validate_chain kernel/locking/lockdep.c:3908 [inline]
__lock_acquire+0x14b8/0x2630 kernel/locking/lockdep.c:5237
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x1cf/0x380 kernel/locking/lockdep.c:5825
__mutex_lock_common kernel/locking/mutex.c:614 [inline]
__mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776
seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
proc_reg_read_iter+0x220/0x310 fs/proc/inode.c:299
copy_splice_read+0x4ba/0xb90 fs/splice.c:362
do_splice_read fs/splice.c:980 [inline]
do_splice_read+0x285/0x370 fs/splice.c:954
splice_file_to_pipe+0x82/0x120 fs/splice.c:1290
do_sendfile+0x366/0xe20 fs/read_write.c:1378
__do_sys_sendfile64 fs/read_write.c:1433 [inline]
__se_sys_sendfile64 fs/read_write.c:1419 [inline]
__x64_sys_sendfile64+0x1d8/0x220 fs/read_write.c:1419
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1d21f9c799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1d22e8d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f1d22215fa0 RCX: 00007f1d21f9c799
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000000
RBP: 00007f1d22032c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000006 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1d22216038 R14: 00007f1d22215fa0 R15: 00007ffd6d3a8778
tipc: Disabling bearer