• Daniel Borkmann's avatar
    debugfs: fix refcount imbalance in start_creating · 0ee9608c
    Daniel Borkmann authored
    In debugfs' start_creating(), we pin the file system to safely access
    its root. When we failed to create a file, we unpin the file system via
    failed_creating() to release the mount count and eventually the reference
    of the vfsmount.
    
    However, when we run into an error during lookup_one_len() when still
    in start_creating(), we only release the parent's mutex but not so the
    reference on the mount. Looks like it was done in the past, but after
    splitting portions of __create_file() into start_creating() and
    end_creating() via 190afd81 ("debugfs: split the beginning and the
    end of __create_file() off"), this seemed missed. Noticed during code
    review.
    
    Fixes: 190afd81 ("debugfs: split the beginning and the end of __create_file() off")
    Cc: stable@vger.kernel.org # v4.0+
    Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
    Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
    0ee9608c
inode.c 20.7 KB