On Mon, Mar 2, 2020 at 12:10 PM Amir Goldstein <amir73il@xxxxxxxxx> wrote: > > ===================================== > > 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: > > [<ffffffff828b7835>] ovl_inode_unlock fs/overlayfs/overlayfs.h:328 [inline] > > [<ffffffff828b7835>] ovl_llseek+0x215/0x2c0 fs/overlayfs/file.c:193 > > but there are no more locks to release! > > > > This is strange. I don't see how that can happen nor how my change would > have caused this regression. If anything, the lock chance may have brought > a bug in stack file ops to light, but don't see the bug. The bug is that ovl_inode_lock() is interruptible and that the caller doesn't check for error. I think the fix is to make this lock uninterruptible (probably rename the current helper to _interruptible and use the current name as the uninterruptible version). Thanks, Miklos
