====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc7-syzkaller-00136-gf4345f05c0df #0 Not tainted ------------------------------------------------------ syz-executor.2/11429 is trying to acquire lock: ffff88807a3e7968 (&ovl_i_lock_key[depth]){+.+.}-{3:3}, at: ovl_inode_lock_interruptible fs/overlayfs/overlayfs.h:654 [inline] ffff88807a3e7968 (&ovl_i_lock_key[depth]){+.+.}-{3:3}, at: ovl_nlink_start+0xdc/0x390 fs/overlayfs/util.c:1162 but task is already holding lock: ffff88807a3e75b0 (&ovl_i_mutex_dir_key[depth]){++++}-{3:3}, at: inode_lock include/linux/fs.h:795 [inline] ffff88807a3e75b0 (&ovl_i_mutex_dir_key[depth]){++++}-{3:3}, at: vfs_rmdir+0x101/0x4c0 fs/namei.c:4195 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&ovl_i_mutex_dir_key[depth]){++++}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 down_read+0xb1/0xa40 kernel/locking/rwsem.c:1526 inode_lock_shared include/linux/fs.h:805 [inline] lookup_slow+0x45/0x70 fs/namei.c:1708 walk_component+0x2e1/0x410 fs/namei.c:2004 lookup_last fs/namei.c:2461 [inline] path_lookupat+0x16f/0x450 fs/namei.c:2485 filename_lookup+0x256/0x610 fs/namei.c:2514 kern_path+0x35/0x50 fs/namei.c:2622 lookup_bdev+0xc5/0x290 block/bdev.c:1136 resume_store+0x1a0/0x710 kernel/power/hibernate.c:1235 kernfs_fop_write_iter+0x3a1/0x500 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:2110 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa84/0xcb0 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (&of->mutex){+.+.}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 kernfs_seq_start+0x53/0x3b0 fs/kernfs/file.c:154 seq_read_iter+0x3d0/0xd60 fs/seq_file.c:225 call_read_iter include/linux/fs.h:2104 [inline] copy_splice_read+0x662/0xb60 fs/splice.c:365 do_splice_read fs/splice.c:985 [inline] splice_file_to_pipe+0x299/0x500 fs/splice.c:1295 do_sendfile+0x515/0xdc0 fs/read_write.c:1301 __do_sys_sendfile64 fs/read_write.c:1362 [inline] __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1348 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (&p->lock){+.+.}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 seq_read_iter+0xb7/0xd60 fs/seq_file.c:182 call_read_iter include/linux/fs.h:2104 [inline] copy_splice_read+0x662/0xb60 fs/splice.c:365 do_splice_read fs/splice.c:985 [inline] splice_file_to_pipe+0x299/0x500 fs/splice.c:1295 do_sendfile+0x515/0xdc0 fs/read_write.c:1301 __do_sys_sendfile64 fs/read_write.c:1362 [inline] __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1348 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (&pipe->mutex){+.+.}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 iter_file_splice_write+0x335/0x14e0 fs/splice.c:687 do_splice_from fs/splice.c:941 [inline] do_splice+0xd77/0x1880 fs/splice.c:1354 __do_splice fs/splice.c:1436 [inline] __do_sys_splice fs/splice.c:1652 [inline] __se_sys_splice+0x331/0x4a0 fs/splice.c:1634 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (sb_writers#4){.+.+}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1664 [inline] sb_start_write include/linux/fs.h:1800 [inline] ovl_start_write+0x11d/0x290 fs/overlayfs/util.c:31 ovl_do_copy_up fs/overlayfs/copy_up.c:967 [inline] ovl_copy_up_one fs/overlayfs/copy_up.c:1168 [inline] ovl_copy_up_flags+0x1105/0x4450 fs/overlayfs/copy_up.c:1223 ovl_link+0x85/0x320 fs/overlayfs/dir.c:703 vfs_link+0x4f5/0x690 fs/namei.c:4605 do_linkat+0x356/0x760 fs/namei.c:4676 __do_sys_linkat fs/namei.c:4704 [inline] __se_sys_linkat fs/namei.c:4701 [inline] __x64_sys_linkat+0xdd/0xf0 fs/namei.c:4701 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&ovl_i_lock_key[depth]){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 ovl_inode_lock_interruptible fs/overlayfs/overlayfs.h:654 [inline] ovl_nlink_start+0xdc/0x390 fs/overlayfs/util.c:1162 ovl_do_remove+0x1fa/0xd90 fs/overlayfs/dir.c:893 vfs_rmdir+0x367/0x4c0 fs/namei.c:4206 do_rmdir+0x3b5/0x580 fs/namei.c:4265 __do_sys_unlinkat fs/namei.c:4441 [inline] __se_sys_unlinkat fs/namei.c:4435 [inline] __x64_sys_unlinkat+0xe0/0xf0 fs/namei.c:4435 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: &ovl_i_lock_key[depth] --> &of->mutex --> &ovl_i_mutex_dir_key[depth] Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ovl_i_mutex_dir_key[depth]); lock(&of->mutex); lock(&ovl_i_mutex_dir_key[depth]); lock(&ovl_i_lock_key[depth]); *** DEADLOCK *** 3 locks held by syz-executor.2/11429: #0: ffff8880225fc420 (sb_writers#35){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:409 #1: ffff88807a3e1e80 (&ovl_i_mutex_dir_key[depth]/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:830 [inline] #1: ffff88807a3e1e80 (&ovl_i_mutex_dir_key[depth]/1){+.+.}-{3:3}, at: do_rmdir+0x263/0x580 fs/namei.c:4253 #2: ffff88807a3e75b0 (&ovl_i_mutex_dir_key[depth]){++++}-{3:3}, at: inode_lock include/linux/fs.h:795 [inline] #2: ffff88807a3e75b0 (&ovl_i_mutex_dir_key[depth]){++++}-{3:3}, at: vfs_rmdir+0x101/0x4c0 fs/namei.c:4195 stack backtrace: CPU: 1 PID: 11429 Comm: syz-executor.2 Not tainted 6.9.0-rc7-syzkaller-00136-gf4345f05c0df #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 ovl_inode_lock_interruptible fs/overlayfs/overlayfs.h:654 [inline] ovl_nlink_start+0xdc/0x390 fs/overlayfs/util.c:1162 ovl_do_remove+0x1fa/0xd90 fs/overlayfs/dir.c:893 vfs_rmdir+0x367/0x4c0 fs/namei.c:4206 do_rmdir+0x3b5/0x580 fs/namei.c:4265 __do_sys_unlinkat fs/namei.c:4441 [inline] __se_sys_unlinkat fs/namei.c:4435 [inline] __x64_sys_unlinkat+0xe0/0xf0 fs/namei.c:4435 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6463a7d547 Code: 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 07 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc9d0a4278 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f6463a7d547 RDX: 0000000000000200 RSI: 00007ffc9d0a5420 RDI: 00000000ffffff9c RBP: 00007f6463ac9336 R08: 00005555564d09db R09: 0000000000000000 R10: 0000000000001000 R11: 0000000000000207 R12: 00007ffc9d0a5420 R13: 00007f6463ac9336 R14: 0000000000090f93 R15: 000000000000001e BTRFS info (device loop2): last unmount of filesystem c9fe44da-de57-406a-8241-57ec7d4412cf