====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz.3.4082/23163 is trying to acquire lock: ffff88805923dce8 (&ovl_i_mutex_dir_key[depth]){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline] ffff88805923dce8 (&ovl_i_mutex_dir_key[depth]){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1932 but task is already holding lock: ffff88805beba488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540 fs/kernfs/file.c:343 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&of->mutex){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x19f/0x1300 kernel/locking/mutex.c:776 kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172 seq_read_iter+0x3f7/0xe10 fs/seq_file.c:226 copy_splice_read+0x5ff/0xaa0 fs/splice.c:363 do_splice_read fs/splice.c:982 [inline] splice_direct_to_actor+0x478/0xc70 fs/splice.c:1086 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x195/0x290 fs/splice.c:1230 do_sendfile+0x535/0x7d0 fs/read_write.c:1372 __do_sys_sendfile64 fs/read_write.c:1433 [inline] __se_sys_sendfile64+0x144/0x1a0 fs/read_write.c:1419 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (&p->lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x19f/0x1300 kernel/locking/mutex.c:776 seq_read_iter+0xb7/0xe10 fs/seq_file.c:183 copy_splice_read+0x5ff/0xaa0 fs/splice.c:363 do_splice_read fs/splice.c:982 [inline] splice_file_to_pipe+0x446/0x6b0 fs/splice.c:1292 do_sendfile+0x4db/0x7d0 fs/read_write.c:1378 __do_sys_sendfile64 fs/read_write.c:1433 [inline] __se_sys_sendfile64+0x144/0x1a0 fs/read_write.c:1419 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (&pipe->mutex){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x19f/0x1300 kernel/locking/mutex.c:776 iter_file_splice_write+0x1ea/0x1100 fs/splice.c:683 do_splice_from fs/splice.c:938 [inline] do_splice+0xee3/0x1910 fs/splice.c:1351 __do_splice fs/splice.c:1433 [inline] __do_sys_splice fs/splice.c:1636 [inline] __se_sys_splice+0x353/0x490 fs/splice.c:1618 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (sb_writers#5){.+.+}-{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+0x4d/0x1c0 include/linux/fs/super.h:125 mnt_want_write+0x41/0x90 fs/namespace.c:493 ovl_xattr_set+0x16c/0x600 fs/overlayfs/xattrs.c:61 __vfs_setxattr+0x43c/0x480 fs/xattr.c:200 __vfs_setxattr_noperm+0x12d/0x660 fs/xattr.c:234 vfs_setxattr+0x163/0x360 fs/xattr.c:321 do_setxattr fs/xattr.c:636 [inline] filename_setxattr+0x296/0x630 fs/xattr.c:664 path_setxattrat+0x3eb/0x440 fs/xattr.c:708 __do_sys_setxattr fs/xattr.c:742 [inline] __se_sys_setxattr fs/xattr.c:738 [inline] __x64_sys_setxattr+0xbc/0xe0 fs/xattr.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&ovl_i_mutex_dir_key[depth]){++++}-{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+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 down_read+0x47/0x2e0 kernel/locking/rwsem.c:1537 inode_lock_shared include/linux/fs.h:1043 [inline] lookup_slow+0x46/0x70 fs/namei.c:1932 walk_component fs/namei.c:2279 [inline] lookup_last fs/namei.c:2780 [inline] path_lookupat+0x3f5/0x8c0 fs/namei.c:2804 filename_lookup+0x256/0x5d0 fs/namei.c:2833 kern_path+0x3d/0x150 fs/namei.c:3040 lookup_bdev+0xc8/0x290 block/bdev.c:1221 resume_store+0x16f/0x4f0 kernel/power/hibernate.c:1306 kernfs_fop_write_iter+0x3af/0x540 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x61d/0xb90 fs/read_write.c:688 ksys_write+0x150/0x270 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/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: &ovl_i_mutex_dir_key[depth] --> &p->lock --> &of->mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&of->mutex); lock(&p->lock); lock(&of->mutex); rlock(&ovl_i_mutex_dir_key[depth]); *** DEADLOCK *** 4 locks held by syz.3.4082/23163: #0: ffff888078b590b8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1261 #1: ffff8880366a4420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2710 [inline] #1: ffff8880366a4420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90 fs/read_write.c:684 #2: ffff88805beba488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540 fs/kernfs/file.c:343 #3: ffff88801f6d04b8 (kn->active#77){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #3: ffff88801f6d04b8 (kn->active#77){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540 fs/kernfs/file.c:344 stack backtrace: CPU: 1 UID: 0 PID: 23163 Comm: syz.3.4082 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2043 check_noncircular+0x12e/0x150 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+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 down_read+0x47/0x2e0 kernel/locking/rwsem.c:1537 inode_lock_shared include/linux/fs.h:1043 [inline] lookup_slow+0x46/0x70 fs/namei.c:1932 walk_component fs/namei.c:2279 [inline] lookup_last fs/namei.c:2780 [inline] path_lookupat+0x3f5/0x8c0 fs/namei.c:2804 filename_lookup+0x256/0x5d0 fs/namei.c:2833 kern_path+0x3d/0x150 fs/namei.c:3040 lookup_bdev+0xc8/0x290 block/bdev.c:1221 resume_store+0x16f/0x4f0 kernel/power/hibernate.c:1306 kernfs_fop_write_iter+0x3af/0x540 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x61d/0xb90 fs/read_write.c:688 ksys_write+0x150/0x270 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa2bcf9c629 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:00007fa2bdda8028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fa2bd215fa0 RCX: 00007fa2bcf9c629 RDX: 0000000000000012 RSI: 00002000000000c0 RDI: 0000000000000007 RBP: 00007fa2bd032b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa2bd216038 R14: 00007fa2bd215fa0 R15: 00007fff800ff628 PM: Image not found (code -6)