Infiniband: Fix potential NULL d_inode dereference

Code that does this:

	if (!(d_unhashed(tmp) && tmp->d_inode)) {
		...
		simple_unlink(parent->d_inode, tmp);
	}

is broken because:

	!(d_unhashed(tmp) && tmp->d_inode)

is equivalent to:

	!d_unhashed(tmp) || !tmp->d_inode

so it is possible to get into simple_unlink() with tmp->d_inode == NULL.

simple_unlink(), however, assumes tmp->d_inode cannot be NULL.

I think that what was meant is this:

	!d_unhashed(tmp) && tmp->d_inode

and that the logical-not operator or the final close-bracket was misplaced.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Bryan O'Sullivan <bos@pathscale.com>
cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
David Howells 2015-01-27 15:01:18 +00:00 committed by Al Viro
parent fed0b588be
commit a95104fd33
2 changed files with 2 additions and 2 deletions

View file

@ -277,7 +277,7 @@ static int remove_file(struct dentry *parent, char *name)
}
spin_lock(&tmp->d_lock);
if (!(d_unhashed(tmp) && tmp->d_inode)) {
if (!d_unhashed(tmp) && tmp->d_inode) {
dget_dlock(tmp);
__d_drop(tmp);
spin_unlock(&tmp->d_lock);

View file

@ -455,7 +455,7 @@ static int remove_file(struct dentry *parent, char *name)
}
spin_lock(&tmp->d_lock);
if (!(d_unhashed(tmp) && tmp->d_inode)) {
if (!d_unhashed(tmp) && tmp->d_inode) {
__d_drop(tmp);
spin_unlock(&tmp->d_lock);
simple_unlink(parent->d_inode, tmp);