Patch "IB/addr: Fix setting source address in addr6_resolve()" has been added to the 4.9-stable tree

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

IB/addr: Fix setting source address in addr6_resolve()

to the 4.9-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:
ib-addr-fix-setting-source-address-in-addr6_resolve.patch
and it can be found in the queue-4.9 subdirectory.

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

From: Roland Dreier <[email protected]>
Date: Tue, 6 Jun 2017 09:22:00 -0700
Subject: IB/addr: Fix setting source address in addr6_resolve()

From: Roland Dreier <[email protected]>

commit 79e25959403e6a79552db28a87abed34de32a1df upstream.

Commit eea40b8f624f ("infiniband: call ipv6 route lookup via the stub interface") introduced a regression in address resolution when connecting to IPv6 destination addresses. The old code called ip6_route_output(), while the new code calls ipv6_stub->ipv6_dst_lookup(). The two are almost the same, except that ipv6_dst_lookup() also calls ip6_route_get_saddr() if the source address is in6addr_any.

This means that the test of ipv6_addr_any(&fl6.saddr) now never succeeds, and so we never copy the source address out. This ends up causing rdma_resolve_addr() to fail, because without a resolved source address, cma_acquire_dev() will fail to find an RDMA device to use. For me, this causes connecting to an NVMe over Fabrics target via RoCE / IPv6 to fail.

Fix this by copying out fl6.saddr if ipv6_addr_any() is true for the original source address passed into addr6_resolve(). We can drop our call to ipv6_dev_get_saddr() because ipv6_dst_lookup() already does that work.

---
 drivers/infiniband/core/addr.c |   12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

@@ -446,15 +446,10 @@ static int addr6_resolve(struct sockaddr
 
 	ret = ipv6_stub->ipv6_dst_lookup(addr->net, NULL, &dst, &fl6);
 	if (ret < 0)
-		goto put;
+		return ret;
 
 	rt = (struct rt6_info *)dst;
-	if (ipv6_addr_any(&fl6.saddr)) {
-		ret = ipv6_dev_get_saddr(addr->net, ip6_dst_idev(dst)->dev,
-					 &fl6.daddr, 0, &fl6.saddr);
-		if (ret)
-			goto put;
-
+	if (ipv6_addr_any(&src_in->sin6_addr)) {
 		src_in->sin6_family = AF_INET6;
 		src_in->sin6_addr = fl6.saddr;
 	}

@@ -471,9 +466,6 @@ static int addr6_resolve(struct sockaddr
 
 	*pdst = dst;
 	return 0;
-put:
-	dst_release(dst);
-	return ret;
 }
 #else
 static int addr6_resolve(struct sockaddr_in6 *src_in,

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

queue-4.9/ib-addr-fix-setting-source-address-in-addr6_resolve.patch