debugfs: fix debugfs_rename parameter checking
commitc87bdb9e8148c9955192d4ef4acdb889a557cd6d
authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 23 Jan 2019 10:27:02 +0000 (23 11:27 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 15 Feb 2019 07:09:12 +0000 (15 08:09 +0100)
tree0cfc30b2d5536df188561707653e10ad2af6c0ff
parentaef80fd68017793d14fddc3b4ef8e1c050b44faf
debugfs: fix debugfs_rename parameter checking

commit d88c93f090f708c18195553b352b9f205e65418f upstream.

debugfs_rename() needs to check that the dentries passed into it really
are valid, as sometimes they are not (i.e. if the return value of
another debugfs call is passed into this one.)  So fix this up by
properly checking if the two parent directories are errors (they are
allowed to be NULL), and if the dentry to rename is not NULL or an
error.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/debugfs/inode.c