Commit e22d24ea authored by Willem de Bruijn's avatar Willem de Bruijn Committed by Luis Henriques

ip: zero sockaddr returned on error queue

commit f812116b upstream.

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: default avatarWillem de Bruijn <willemb@google.com>

----

Also verified that there is no padding between errhdr.ee and
errhdr.offender that could leak additional kernel data.
Acked-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
[ luis: backported to 3.16: based on davem's backport to 3.14 ]
Signed-off-by: default avatarLuis Henriques <luis.henriques@canonical.com>
parent c8d4e7cf
...@@ -443,15 +443,11 @@ int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) ...@@ -443,15 +443,11 @@ int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err)); memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
sin = &errhdr.offender; sin = &errhdr.offender;
sin->sin_family = AF_UNSPEC; memset(sin, 0, sizeof(*sin));
if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP) { if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP) {
struct inet_sock *inet = inet_sk(sk);
sin->sin_family = AF_INET; sin->sin_family = AF_INET;
sin->sin_addr.s_addr = ip_hdr(skb)->saddr; sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
sin->sin_port = 0; if (inet_sk(sk)->cmsg_flags)
memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
if (inet->cmsg_flags)
ip_cmsg_recv(msg, skb); ip_cmsg_recv(msg, skb);
} }
......
...@@ -382,11 +382,10 @@ int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) ...@@ -382,11 +382,10 @@ 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)); memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
sin = &errhdr.offender; sin = &errhdr.offender;
sin->sin6_family = AF_UNSPEC; memset(sin, 0, sizeof(*sin));
if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) { if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
sin->sin6_family = AF_INET6; sin->sin6_family = AF_INET6;
sin->sin6_flowinfo = 0;
sin->sin6_port = 0;
if (np->rxopt.all) if (np->rxopt.all)
ip6_datagram_recv_common_ctl(sk, msg, skb); ip6_datagram_recv_common_ctl(sk, msg, skb);
if (skb->protocol == htons(ETH_P_IPV6)) { if (skb->protocol == htons(ETH_P_IPV6)) {
...@@ -397,12 +396,9 @@ int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) ...@@ -397,12 +396,9 @@ int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
ipv6_iface_scope_id(&sin->sin6_addr, ipv6_iface_scope_id(&sin->sin6_addr,
IP6CB(skb)->iif); IP6CB(skb)->iif);
} else { } else {
struct inet_sock *inet = inet_sk(sk);
ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
&sin->sin6_addr); &sin->sin6_addr);
sin->sin6_scope_id = 0; if (inet_sk(sk)->cmsg_flags)
if (inet->cmsg_flags)
ip_cmsg_recv(msg, skb); ip_cmsg_recv(msg, skb);
} }
} }
......
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