====================================================== WARNING: possible circular locking dependency detected 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Not tainted ------------------------------------------------------ syz-executor.2/6582 is trying to acquire lock: ffff88802b0ad088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_llseek+0x7e/0x2a0 fs/kernfs/file.c:867 but task is already holding lock: ffff88805b772238 (&ovl_i_lock_key[depth]){+.+.}-{3:3}, at: ovl_inode_lock fs/overlayfs/overlayfs.h:649 [inline] ffff88805b772238 (&ovl_i_lock_key[depth]){+.+.}-{3:3}, at: ovl_llseek+0x26b/0x470 fs/overlayfs/file.c:214 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&ovl_i_lock_key[depth]){+.+.}-{3:3}: lock_acquire+0x1e4/0x530 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:4209 do_rmdir+0x3b5/0x580 fs/namei.c:4268 __do_sys_rmdir fs/namei.c:4287 [inline] __se_sys_rmdir fs/namei.c:4285 [inline] __x64_sys_rmdir+0x49/0x60 fs/namei.c:4285 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 -> #2 (&ovl_i_mutex_dir_key[depth]#2){++++}-{3:3}: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 down_read+0xb1/0xa40 kernel/locking/rwsem.c:1526 inode_lock_shared include/linux/fs.h:803 [inline] lookup_slow fs/namei.c:1708 [inline] lookup_one_unlocked+0x197/0x290 fs/namei.c:2817 ovl_lookup_positive_unlocked fs/overlayfs/namei.c:210 [inline] ovl_lookup_single+0x200/0xbd0 fs/overlayfs/namei.c:240 ovl_lookup_layer+0x417/0x510 fs/overlayfs/namei.c:333 ovl_lookup+0xcf7/0x2a60 fs/overlayfs/namei.c:1124 __lookup_slow+0x28c/0x3f0 fs/namei.c:1692 lookup_slow+0x53/0x70 fs/namei.c:1709 walk_component fs/namei.c:2004 [inline] link_path_walk+0x9ea/0xea0 fs/namei.c:2331 path_parentat fs/namei.c:2532 [inline] __filename_parentat+0x263/0x6f0 fs/namei.c:2556 filename_parentat fs/namei.c:2574 [inline] do_renameat2+0x373/0x13f0 fs/namei.c:4947 __do_sys_rename fs/namei.c:5087 [inline] __se_sys_rename fs/namei.c:5085 [inline] __x64_sys_rename+0x86/0xa0 fs/namei.c:5085 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 -> #1 (&ovl_i_mutex_dir_key[depth]#3){++++}-{3:3}: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 down_read+0xb1/0xa40 kernel/locking/rwsem.c:1526 inode_lock_shared include/linux/fs.h:803 [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:1072 resume_store+0x1a0/0x710 kernel/power/hibernate.c:1235 kernfs_fop_write_iter+0x3a4/0x500 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:2108 [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_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 -> #0 (&of->mutex){+.+.}-{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+0x1e4/0x530 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 kernfs_fop_llseek+0x7e/0x2a0 fs/kernfs/file.c:867 ovl_llseek+0x314/0x470 fs/overlayfs/file.c:218 vfs_llseek fs/read_write.c:289 [inline] ksys_lseek fs/read_write.c:302 [inline] __do_sys_lseek fs/read_write.c:313 [inline] __se_sys_lseek fs/read_write.c:311 [inline] __x64_sys_lseek+0x153/0x1e0 fs/read_write.c:311 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 other info that might help us debug this: Chain exists of: &of->mutex --> &ovl_i_mutex_dir_key[depth]#2 --> &ovl_i_lock_key[depth] Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ovl_i_lock_key[depth]); lock(&ovl_i_mutex_dir_key[depth]#2); lock(&ovl_i_lock_key[depth]); lock(&of->mutex); *** DEADLOCK *** 2 locks held by syz-executor.2/6582: #0: ffff88802ac254c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x259/0x320 fs/file.c:1191 #1: ffff88805b772238 (&ovl_i_lock_key[depth]){+.+.}-{3:3}, at: ovl_inode_lock fs/overlayfs/overlayfs.h:649 [inline] #1: ffff88805b772238 (&ovl_i_lock_key[depth]){+.+.}-{3:3}, at: ovl_llseek+0x26b/0x470 fs/overlayfs/file.c:214 stack backtrace: CPU: 0 PID: 6582 Comm: syz-executor.2 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 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+0x1e4/0x530 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 kernfs_fop_llseek+0x7e/0x2a0 fs/kernfs/file.c:867 ovl_llseek+0x314/0x470 fs/overlayfs/file.c:218 vfs_llseek fs/read_write.c:289 [inline] ksys_lseek fs/read_write.c:302 [inline] __do_sys_lseek fs/read_write.c:313 [inline] __se_sys_lseek fs/read_write.c:311 [inline] __x64_sys_lseek+0x153/0x1e0 fs/read_write.c:311 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f880087de69 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f880165b0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000008 RAX: ffffffffffffffda RBX: 00007f88009abf80 RCX: 00007f880087de69 RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007f88008ca47a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f88009abf80 R15: 00007fff589cb358 fuse: Bad value for 'user_id'