Patch "RDMA/core: Do not use invalid destination in determining port reuse" has been added to the 4.15-stable tree

This is a note to let you know that I've just added the patch titled

RDMA/core: Do not use invalid destination in determining port reuse

to the 4.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
rdma-core-do-not-use-invalid-destination-in-determining-port-reuse.patch
and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Tatyana Nikolova <[email protected]>
Date: Mon, 12 Mar 2018 17:14:02 -0500
Subject: RDMA/core: Do not use invalid destination in determining port reuse

From: Tatyana Nikolova <[email protected]>

commit 9dea9a2ff61c5efb4d4937ae23b14babd25a5547 upstream.

cma_port_is_unique() allows local port reuse if the quad (source address and port, destination address and port) for this connection is unique. However, if the destination info is zero or unspecified, it can't make a correct decision but still allows port reuse. For example, sometimes rdma_bind_addr() is called with unspecified destination and reusing the port can lead to creating a connection with a duplicate quad, after the destination is resolved. The issue manifests when MPI scale-up tests hang after the duplicate quad is used.

Set the destination address family and add checks for zero destination address and port to prevent source port reuse based on invalid destination.

---
 drivers/infiniband/core/cma.c |   12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

@@ -3013,7 +3013,8 @@ static int cma_port_is_unique(struct rdm
 			continue;
 
 		/* different dest port -> unique */
-		if (!cma_any_port(cur_daddr) &&
+		if (!cma_any_port(daddr) &&
+		    !cma_any_port(cur_daddr) &&
 		    (dport != cur_dport))
 			continue;
 

@@ -3024,7 +3025,8 @@ static int cma_port_is_unique(struct rdm
 			continue;
 
 		/* different dst address -> unique */
-		if (!cma_any_addr(cur_daddr) &&
+		if (!cma_any_addr(daddr) &&
+		    !cma_any_addr(cur_daddr) &&
 		    cma_addr_cmp(daddr, cur_daddr))
 			continue;
 

@@ -3322,13 +3324,13 @@ int rdma_bind_addr(struct rdma_cm_id *id
 		}
 #endif
 	}
+	daddr = cma_dst_addr(id_priv);
+	daddr->sa_family = addr->sa_family;
+
 	ret = cma_get_port(id_priv);
 	if (ret)
 		goto err2;
 
-	daddr = cma_dst_addr(id_priv);
-	daddr->sa_family = addr->sa_family;
-
 	return 0;
 err2:
 	if (id_priv->cma_dev)

Patches currently in stable-queue which might be from [email protected] are

queue-4.15/rdma-core-do-not-use-invalid-destination-in-determining-port-reuse.patch queue-4.15/rdma-iwpm-fix-uninitialized-error-code-in-iwpm_send_mapinfo.patch