netlink: 5 bytes leftover after parsing attributes in process `syz-executor6'.

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[ BUG: lock held when returning to user space! ]
4.9.124+ #34 Not tainted
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syz-executor2/6304 is leaving the kernel with locks still held!
1 lock held by syz-executor2/6304:
 #0:  (&fi->mutex){+.+.+.}, at: [<ffffffff8185d5e2>] fuse_lock_inode+0xa2/0xd0 fs/fuse/inode.c:362