[PATCH 3.19 029/177] net: ping: Return EAFNOSUPPORT when appropriate.

Greg Kroah-Hartman
2015-03-16T16:00:00Z

From: Lorenzo Colitti <lorenzo@google.com>

[ Upstream commit 9145736d4862145684009d6a72a6e61324a9439e ]

1. For an IPv4 ping socket, ping_check_bind_addr does not check
the family of the socket address that's passed in. Instead,
make it behave like inet_bind, which enforces either that the
address family is AF_INET, or that the family is AF_UNSPEC and
the address is 0.0.0.0.
2. For an IPv6 ping socket, ping_check_bind_addr returns EINVAL
if the socket family is not AF_INET6. Return EAFNOSUPPORT
instead, for consistency with inet6_bind.
3. Make ping_v4_sendmsg and ping_v6_sendmsg return EAFNOSUPPORT
instead of EINVAL if an incorrect socket address structure is
passed in.
4. Make IPv6 ping sockets be IPv6-only. The code does not support
IPv4, and it cannot easily be made to support IPv4 because
the protocol numbers for ICMP and ICMPv6 are different. This
makes connect(::ffff:192.0.2.1) fail with EAFNOSUPPORT instead
of making the socket unusable.

Among other things, this fixes an oops that can be triggered by:

int s = socket(AF_INET, SOCK_DGRAM, IPPROTO_ICMP);
struct sockaddr_in6 sin6 = {
.sin6_family = AF_INET6,
.sin6_addr = in6addr_any,
};
bind(s, (struct sockaddr *) &sin6, sizeof(sin6));

Change-Id: If06ca86d9f1e4593c0d6df174caca3487c57a241
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/ipv4/ping.c | 12 ++++++++++--
net/ipv6/ping.c | 5 +++--
2 files changed, 13 insertions(+), 4 deletions(-)

--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -259,6 +259,9 @@ int ping_init_sock(struct sock *sk)
kgid_t low, high;
int ret = 0;

+ if (sk->sk_family == AF_INET6)
+ sk->sk_ipv6only = 1;
+
inet_get_ping_group_range_net(net, &low, &high);
if (gid_lte(low, group) && gid_lte(group, high))
return 0;
@@ -305,6 +308,11 @@ static int ping_check_bind_addr(struct s
if (addr_len < sizeof(*addr))
return -EINVAL;

+ if (addr->sin_family != AF_INET &&
+ !(addr->sin_family == AF_UNSPEC &&
+ addr->sin_addr.s_addr == htonl(INADDR_ANY)))
+ return -EAFNOSUPPORT;
+
pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));

@@ -330,7 +338,7 @@ static int ping_check_bind_addr(struct s
return -EINVAL;

if (addr->sin6_family != AF_INET6)
- return -EINVAL;
+ return -EAFNOSUPPORT;

pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n",
sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port));
@@ -716,7 +724,7 @@ static int ping_v4_sendmsg(struct kiocb
if (msg->msg_namelen < sizeof(*usin))
return -EINVAL;
if (usin->sin_family != AF_INET)
- return -EINVAL;
+ return -EAFNOSUPPORT;
daddr = usin->sin_addr.s_addr;
/* no remote port */
} else {
--- a/net/ipv6/ping.c
+++ b/net/ipv6/ping.c
@@ -102,9 +102,10 @@ int ping_v6_sendmsg(struct kiocb *iocb,

if (msg->msg_name) {
DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name);
- if (msg->msg_namelen < sizeof(struct sockaddr_in6) ||
- u->sin6_family != AF_INET6) {
+ if (msg->msg_namelen < sizeof(*u))
return -EINVAL;
+ if (u->sin6_family != AF_INET6) {
+ return -EAFNOSUPPORT;
}
if (sk->sk_bound_dev_if &&
sk->sk_bound_dev_if != u->sin6_scope_id) {