===================================== WARNING: bad unlock balance detected! 5.6.0-rc3-syzkaller #0 Not tainted ------------------------------------- syz-executor194/8947 is trying to release lock (&ovl_i_lock_key[depth]) at: [] ovl_inode_unlock fs/overlayfs/overlayfs.h:328 [inline] [] ovl_llseek+0x215/0x2c0 fs/overlayfs/file.c:193 but there are no more locks to release! other info that might help us debug this: 1 lock held by syz-executor194/8947: #0: ffff88809742ade0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x279/0x310 fs/file.c:821 stack backtrace: CPU: 0 PID: 8947 Comm: syz-executor194 Not tainted 5.6.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fb/0x318 lib/dump_stack.c:118 print_unlock_imbalance_bug+0x20b/0x240 kernel/locking/lockdep.c:4007 __lock_release kernel/locking/lockdep.c:4241 [inline] lock_release+0x469/0x710 kernel/locking/lockdep.c:4502 __mutex_unlock_slowpath+0x80/0x5b0 kernel/locking/mutex.c:1228 mutex_unlock+0xd/0x10 kernel/locking/mutex.c:740 ovl_inode_unlock fs/overlayfs/overlayfs.h:328 [inline] ovl_llseek+0x215/0x2c0 fs/overlayfs/file.c:193 vfs_llseek fs/read_write.c:300 [inline] ksys_lseek fs/read_write.c:313 [inline] __do_sys_lseek fs/read_write.c:324 [inline] __se_sys_lseek fs/read_write.c:322 [inline] __x64_sys_lseek+0x15f/0x1f0 fs/read_write.c:322 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x445df9 Code: e8 ac b8 02 00 48 83 c4 18 c3 0f 1f 80 00 00 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 0f 83 2b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ff735aecce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000008 RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000445df