inet: fix addr_len/msg->msg_namelen assignment in recv_error and rxpmtu functions
Commit bceaa90240b6019ed73b49965eac7d167610be69 ("inet: prevent leakage
of uninitialized memory to user in recv syscalls") conditionally updated
addr_len if the msg_name is written to. The recv_error and rxpmtu
functions relied on the recvmsg functions to set up addr_len before.
As this does not happen any more we have to pass addr_len to those
functions as well and set it to the size of the corresponding sockaddr
length.
This broke traceroute and such.
Fixes: bceaa90240b6 ("inet: prevent leakage of uninitialized memory to user in recv syscalls")
Reported-by: Brad Spengler <spender@grsecurity.net>
Reported-by: Tom Labanowski
Cc: mpb <mpb.mail@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 3f85826..ddf32a6 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -386,7 +386,7 @@
/*
* Handle MSG_ERRQUEUE
*/
-int ip_recv_error(struct sock *sk, struct msghdr *msg, int len)
+int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
{
struct sock_exterr_skb *serr;
struct sk_buff *skb, *skb2;
@@ -423,6 +423,7 @@
serr->addr_offset);
sin->sin_port = serr->port;
memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
+ *addr_len = sizeof(*sin);
}
memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 876c6ca..840cf1b 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -841,10 +841,11 @@
if (flags & MSG_ERRQUEUE) {
if (family == AF_INET) {
- return ip_recv_error(sk, msg, len);
+ return ip_recv_error(sk, msg, len, addr_len);
#if IS_ENABLED(CONFIG_IPV6)
} else if (family == AF_INET6) {
- return pingv6_ops.ipv6_recv_error(sk, msg, len);
+ return pingv6_ops.ipv6_recv_error(sk, msg, len,
+ addr_len);
#endif
}
}
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 5cb8ddb..23c3e5b 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -697,7 +697,7 @@
goto out;
if (flags & MSG_ERRQUEUE) {
- err = ip_recv_error(sk, msg, len);
+ err = ip_recv_error(sk, msg, len, addr_len);
goto out;
}
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 5944d7d..44dfaa0 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1236,7 +1236,7 @@
bool slow;
if (flags & MSG_ERRQUEUE)
- return ip_recv_error(sk, msg, len);
+ return ip_recv_error(sk, msg, len, addr_len);
try_again:
skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index a454b0f..d690204 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -318,7 +318,7 @@
/*
* Handle MSG_ERRQUEUE
*/
-int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
+int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct sock_exterr_skb *serr;
@@ -369,6 +369,7 @@
&sin->sin6_addr);
sin->sin6_scope_id = 0;
}
+ *addr_len = sizeof(*sin);
}
memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
@@ -423,7 +424,8 @@
/*
* Handle IPV6_RECVPATHMTU
*/
-int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len)
+int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
+ int *addr_len)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct sk_buff *skb;
@@ -457,6 +459,7 @@
sin->sin6_port = 0;
sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
+ *addr_len = sizeof(*sin);
}
put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
diff --git a/net/ipv6/ping.c b/net/ipv6/ping.c
index 8815e31..a83243c 100644
--- a/net/ipv6/ping.c
+++ b/net/ipv6/ping.c
@@ -57,7 +57,8 @@
/* Compatibility glue so we can support IPv6 when it's compiled as a module */
-static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
+static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
+ int *addr_len)
{
return -EAFNOSUPPORT;
}
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index e24ff1d..7fb4e14 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -466,10 +466,10 @@
return -EOPNOTSUPP;
if (flags & MSG_ERRQUEUE)
- return ipv6_recv_error(sk, msg, len);
+ return ipv6_recv_error(sk, msg, len, addr_len);
if (np->rxpmtu && np->rxopt.bits.rxpmtu)
- return ipv6_recv_rxpmtu(sk, msg, len);
+ return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
skb = skb_recv_datagram(sk, flags, noblock, &err);
if (!skb)
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 81eb8cf..bcd5699 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -393,10 +393,10 @@
bool slow;
if (flags & MSG_ERRQUEUE)
- return ipv6_recv_error(sk, msg, len);
+ return ipv6_recv_error(sk, msg, len, addr_len);
if (np->rxpmtu && np->rxopt.bits.rxpmtu)
- return ipv6_recv_rxpmtu(sk, msg, len);
+ return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
try_again:
skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c
index cfd6530..d9b437e 100644
--- a/net/l2tp/l2tp_ip6.c
+++ b/net/l2tp/l2tp_ip6.c
@@ -665,7 +665,7 @@
*addr_len = sizeof(*lsa);
if (flags & MSG_ERRQUEUE)
- return ipv6_recv_error(sk, msg, len);
+ return ipv6_recv_error(sk, msg, len, addr_len);
skb = skb_recv_datagram(sk, flags, noblock, &err);
if (!skb)