From 11235a669e34cf610cf315d8e8d3a37d1d9d9611 Mon Sep 17 00:00:00 2001 From: Willem de Bruijn Date: Thu, 15 Jan 2015 13:18:40 -0500 Subject: ip: zero sockaddr returned on error queue [ Upstream commit f812116b174e59a350acc8e4856213a166a91222 ] The sockaddr is returned in IP(V6)_RECVERR as part of errhdr. That structure is defined and allocated on the stack as struct { struct sock_extended_err ee; struct sockaddr_in(6) offender; } errhdr; The second part is only initialized for certain SO_EE_ORIGIN values. Always initialize it completely. An MTU exceeded error on a SOCK_RAW/IPPROTO_RAW is one example that would return uninitialized bytes. Signed-off-by: Willem de Bruijn ---- Also verified that there is no padding between errhdr.ee and errhdr.offender that could leak additional kernel data. Acked-by: Eric Dumazet Signed-off-by: David S. Miller [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- net/ipv6/datagram.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c index 3c7c948..33719b7 100644 --- a/net/ipv6/datagram.c +++ b/net/ipv6/datagram.c @@ -371,12 +371,10 @@ int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err)); sin = &errhdr.offender; - sin->sin6_family = AF_UNSPEC; + memset(sin, 0, sizeof(*sin)); + if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) { sin->sin6_family = AF_INET6; - sin->sin6_flowinfo = 0; - sin->sin6_port = 0; - sin->sin6_scope_id = 0; if (skb->protocol == htons(ETH_P_IPV6)) { ipv6_addr_copy(&sin->sin6_addr, &ipv6_hdr(skb)->saddr); if (np->rxopt.all) @@ -384,11 +382,9 @@ int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL) sin->sin6_scope_id = IP6CB(skb)->iif; } else { - struct inet_sock *inet = inet_sk(sk); - ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, &sin->sin6_addr); - if (inet->cmsg_flags) + if (inet_sk(sk)->cmsg_flags) ip_cmsg_recv(msg, skb); } } -- cgit v1.1