============================================ WARNING: possible recursive locking detected 4.19.211-syzkaller #0 Not tainted -------------------------------------------- syz-executor.3/15798 is trying to acquire lock: 000000000be7ed93 (&type->i_mutex_dir_key#15){++++}, at: inode_lock include/linux/fs.h:748 [inline] 000000000be7ed93 (&type->i_mutex_dir_key#15){++++}, at: fuse_reverse_inval_entry+0x2e1/0x660 fs/fuse/dir.c:1006 but task is already holding lock: 000000001be41ac5 (&type->i_mutex_dir_key#15){++++}, at: inode_lock include/linux/fs.h:748 [inline] 000000001be41ac5 (&type->i_mutex_dir_key#15){++++}, at: fuse_reverse_inval_entry+0xaa/0x660 fs/fuse/dir.c:987 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&type->i_mutex_dir_key#15); lock(&type->i_mutex_dir_key#15); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by syz-executor.3/15798: #0: 000000002c24b674 (&fc->killsb){++++}, at: fuse_notify_delete fs/fuse/dev.c:1582 [inline] #0: 000000002c24b674 (&fc->killsb){++++}, at: fuse_notify fs/fuse/dev.c:1819 [inline] #0: 000000002c24b674 (&fc->killsb){++++}, at: fuse_dev_do_write+0x2343/0x2bc0 fs/fuse/dev.c:1894 #1: 000000001be41ac5 (&type->i_mutex_dir_key#15){++++}, at: inode_lock include/linux/fs.h:748 [inline] #1: 000000001be41ac5 (&type->i_mutex_dir_key#15){++++}, at: fuse_reverse_inval_entry+0xaa/0x660 fs/fuse/dir.c:987 stack backtrace: CPU: 0 PID: 15798 Comm: syz-executor.3 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_deadlock_bug kernel/locking/lockdep.c:1764 [inline] check_deadlock kernel/locking/lockdep.c:1808 [inline] validate_chain kernel/locking/lockdep.c:2404 [inline] __lock_acquire.cold+0x121/0x57e kernel/locking/lockdep.c:3416 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 down_write+0x34/0x90 kernel/locking/rwsem.c:70 inode_lock include/linux/fs.h:748 [inline] fuse_reverse_inval_entry+0x2e1/0x660 fs/fuse/dir.c:1006 fuse_notify_delete fs/fuse/dev.c:1585 [inline] fuse_notify fs/fuse/dev.c:1819 [inline] fuse_dev_do_write+0x239e/0x2bc0 fs/fuse/dev.c:1894 fuse_dev_write+0x153/0x1e0 fs/fuse/dev.c:1978 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x51b/0x770 fs/read_write.c:487 vfs_write+0x1f3/0x540 fs/read_write.c:549 ksys_write+0x12b/0x2a0 fs/read_write.c:599 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fb9b8e510c9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb9b73a2168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fb9b8f71050 RCX: 00007fb9b8e510c9 RDX: 000000000000002a RSI: 0000000020000080 RDI: 0000000000000003 RBP: 00007fb9b8eacae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd72421f3f R14: 00007fb9b73a2300 R15: 0000000000022000 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.5'. ntfs: volume version 3.1. ntfs: volume version 3.1. net_ratelimit: 1 callbacks suppressed do_dccp_setsockopt: sockopt(CHANGE_L/R) is deprecated: fix your app do_dccp_setsockopt: sockopt(CHANGE_L/R) is deprecated: fix your app do_dccp_setsockopt: sockopt(CHANGE_L/R) is deprecated: fix your app do_dccp_setsockopt: sockopt(CHANGE_L/R) is deprecated: fix your app do_dccp_setsockopt: sockopt(CHANGE_L/R) is deprecated: fix your app do_dccp_setsockopt: sockopt(CHANGE_L/R) is deprecated: fix your app do_dccp_setsockopt: sockopt(CHANGE_L/R) is deprecated: fix your app Enabling of bearer rejected, failed to enable media Enabling of bearer rejected, failed to enable media Enabling of bearer rejected, failed to enable media Enabling of bearer rejected, failed to enable media