Patch "net: Only honor ifindex in IP_PKTINFO if non-0" 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

net: Only honor ifindex in IP_PKTINFO if non-0

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:
net-only-honor-ifindex-in-ip_pktinfo-if-non-0.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: David Ahern <[email protected]>
Date: Fri, 16 Feb 2018 11:03:03 -0800
Subject: net: Only honor ifindex in IP_PKTINFO if non-0

From: David Ahern <[email protected]>

[ Upstream commit 2cbb4ea7de167b02ffa63e9cdfdb07a7e7094615 ]

Only allow ifindex from IP_PKTINFO to override SO_BINDTODEVICE settings if the index is actually set in the message.

---
 net/ipv4/ip_sockglue.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

@@ -242,7 +242,8 @@ int ip_cmsg_send(struct sock *sk, struct
 			src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
 			if (!ipv6_addr_v4mapped(&src_info->ipi6_addr))
 				return -EINVAL;
-			ipc->oif = src_info->ipi6_ifindex;
+			if (src_info->ipi6_ifindex)
+				ipc->oif = src_info->ipi6_ifindex;
 			ipc->addr = src_info->ipi6_addr.s6_addr32[3];
 			continue;
 		}

@@ -272,7 +273,8 @@ int ip_cmsg_send(struct sock *sk, struct
 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
 				return -EINVAL;
 			info = (struct in_pktinfo *)CMSG_DATA(cmsg);
-			ipc->oif = info->ipi_ifindex;
+			if (info->ipi_ifindex)
+				ipc->oif = info->ipi_ifindex;
 			ipc->addr = info->ipi_spec_dst.s_addr;
 			break;
 		}

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

queue-4.9/net-only-honor-ifindex-in-ip_pktinfo-if-non-0.patch