If debugfs were to return a non-NULL error for a debugfs call, using
that pointer later in debugfs_create_files() would crash.
Fix that by properly checking the pointer before referencing it.
Reported-by: Michal Hocko <mhocko@kernel.org>
Reported-and-tested-by: syzbot+b382ba6a802a3d242790@syzkaller.appspotmail.com
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
static bool debugfs_create_files(struct dentry *parent, void *data,
const struct blk_mq_debugfs_attr *attr)
{
+ if (IS_ERR_OR_NULL(parent))
+ return false;
+
d_inode(parent)->i_private = data;
for (; attr->name; attr++) {