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%3Ba=su...

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 stable@vger.kernel.org know about it.

From 9dea9a2ff61c5efb4d4937ae23b14babd25a5547 Mon Sep 17 00:00:00 2001

From: Tatyana Nikolova tatyana.e.nikolova@intel.com Date: Mon, 12 Mar 2018 17:14:02 -0500 Subject: RDMA/core: Do not use invalid destination in determining port reuse

From: Tatyana Nikolova tatyana.e.nikolova@intel.com

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.

Fixes: 19b752a19dce ("IB/cma: Allow port reuse for rdma_id") Reviewed-by: Sean Hefty sean.hefty@intel.com Signed-off-by: Tatyana Nikolova tatyana.e.nikolova@intel.com Signed-off-by: Shiraz Saleem shiraz.saleem@intel.com Signed-off-by: Doug Ledford dledford@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

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

--- a/drivers/infiniband/core/cma.c +++ b/drivers/infiniband/core/cma.c @@ -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 tatyana.e.nikolova@intel.com 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