Commit 80975d21 authored Aug 05, 2011 by Jeff Layton Committed by Steve French Aug 05, 2011

cifs: cope with negative dentries in cifs_get_root

The loop around lookup_one_len doesn't handle the case where it might
return a negative dentry, which can cause an oops on the next pass
through the loop. Check for that and break out of the loop with an
error of -ENOENT if there is one.

Fixes the panic reported here:

    https://bugzilla.redhat.com/show_bug.cgi?id=727927



Reported-by: TR Bentley <home@trarbentley.net>
Reported-by: Iain Arnell <iarnell@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

parent f9e8c450

fs/cifs/cifsfs.c

+4 −0

Original line number	Original line	Diff line number	Diff line
	@@ -563,6 +563,10 @@ cifs_get_root(struct smb_vol vol, struct super_block sb)
	mutex_unlock(&dir->i_mutex);		mutex_unlock(&dir->i_mutex);
	dput(dentry);		dput(dentry);
	dentry = child;		dentry = child;
			if (!dentry->d_inode) {
			dput(dentry);
			dentry = ERR_PTR(-ENOENT);
			}
	} while (!IS_ERR(dentry));		} while (!IS_ERR(dentry));
	_FreeXid(xid);		_FreeXid(xid);
	kfree(full_path);		kfree(full_path);