When register_session() is given an out-of-range argument for mds, ceph_mdsmap_get_addr() will return a null pointer, which would be given to ceph_con_open() & be dereferenced, causing a kernel oops. This fixes bug #4685 in the Ceph bug tracker <http://tracker.ceph.com/issues/4685>. Signed-off-by: Nathaniel Yazdani <n1ght.4nd.d4y@xxxxxxxxx> --- diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index 187bf21..ddff072 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -414,6 +414,9 @@ static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc, { struct ceph_mds_session *s; + if (mds >= mdsc->mdsmap->m_max_mds) + return ERR_PTR(-EINVAL); + s = kzalloc(sizeof(*s), GFP_NOFS); if (!s) return ERR_PTR(-ENOMEM); -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html