RDMA/cma: Use correct address when leaving multicast group

BugLink: https://bugs.launchpad.net/bugs/1960516
commit d9e410ebbed9d091b97bdf45b8a3792e2878dc48 upstream.

In RoCE we should use cma_iboe_set_mgid() and not cma_set_mgid to generate
the mgid, otherwise we will generate an IGMP for an incorrect address.

Fixes: b5de0c60cc30 ("RDMA/cma: Fix use after free race in roce multicast join")
Link: https://lore.kernel.org/r/913bc6783fd7a95fe71ad9454e01653ee6fb4a9a.1642491047.git.leonro@nvidia.com
Signed-off-by: Maor Gottlieb <maorg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 3d419741e8916cfe6b36bd69c0a67870c73ae788..13679c7b65774ac934118843d16477599945acf3 100644 (file)
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -67,8 +67,8 @@ static const char * const cma_events[] = {
        [RDMA_CM_EVENT_TIMEWAIT_EXIT]    = "timewait exit",
 };
 
-static void cma_set_mgid(struct rdma_id_private *id_priv, struct sockaddr *addr,
-                        union ib_gid *mgid);
+static void cma_iboe_set_mgid(struct sockaddr *addr, union ib_gid *mgid,
+                             enum ib_gid_type gid_type);
 
 const char *__attribute_const__ rdma_event_msg(enum rdma_cm_event_type event)
 {
@@ -1844,17 +1844,19 @@ static void destroy_mc(struct rdma_id_private *id_priv,
                if (dev_addr->bound_dev_if)
                        ndev = dev_get_by_index(dev_addr->net,
                                                dev_addr->bound_dev_if);
-               if (ndev) {
+               if (ndev && !send_only) {
+                       enum ib_gid_type gid_type;
                        union ib_gid mgid;
 
-                       cma_set_mgid(id_priv, (struct sockaddr *)&mc->addr,
-                                    &mgid);
-
-                       if (!send_only)
-                               cma_igmp_send(ndev, &mgid, false);
-
-                       dev_put(ndev);
+                       gid_type = id_priv->cma_dev->default_gid_type
+                                          [id_priv->id.port_num -
+                                           rdma_start_port(
+                                                   id_priv->cma_dev->device)];
+                       cma_iboe_set_mgid((struct sockaddr *)&mc->addr, &mgid,
+                                         gid_type);
+                       cma_igmp_send(ndev, &mgid, false);
                }
+               dev_put(ndev);
 
                cancel_work_sync(&mc->iboe_join.work);
        }