From: David Ahern Date: Fri, 16 Feb 2018 19:03:03 +0000 (-0800) Subject: net: Only honor ifindex in IP_PKTINFO if non-0 X-Git-Tag: v3.18.103~65 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=4544f23db6149301fbd6596d2e670f471fbc4f78;p=thirdparty%2Fkernel%2Fstable.git net: Only honor ifindex in IP_PKTINFO if non-0 [ Upstream commit 2cbb4ea7de167b02ffa63e9cdfdb07a7e7094615 ] Only allow ifindex from IP_PKTINFO to override SO_BINDTODEVICE settings if the index is actually set in the message. Signed-off-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index 30b08bfc1ddee..a0b6ca2807ccd 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -206,7 +206,8 @@ int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc, 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; } @@ -227,7 +228,8 @@ int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc, 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; }