[ 082/143] inet: fix addr_len/msg->msg_namelen assignment in recv_error and

Willy Tarreau
2014-05-12T01:41:54Z

rxpmtu functions

From: Hannes Frederic Sowa <hannes@stressinduktion.org>

[ Upstream commit 85fbaa75037d0b6b786ff18658ddf0b4014ce2a4 ]

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>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
include/net/ip.h | 2 +-
include/net/ipv6.h | 3 ++-
net/ipv4/ip_sockglue.c | 3 ++-
net/ipv4/raw.c | 2 +-
net/ipv4/udp.c | 2 +-
net/ipv6/datagram.c | 3 ++-
net/ipv6/raw.c | 2 +-
net/ipv6/udp.c | 2 +-
8 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/include/net/ip.h b/include/net/ip.h
index a7d4675..e6860b1 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -391,7 +391,7 @@ extern int compat_ip_getsockopt(struct sock *sk, int level,
int optname, char __user *optval, int __user *optlen);
extern int ip_ra_control(struct sock *sk, unsigned char on, void (*destructor)(struct sock *));

-extern int ip_recv_error(struct sock *sk, struct msghdr *msg, int len);
+extern int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
extern void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
__be16 port, u32 info, u8 *payload);
extern void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 52d86da..cf928c4 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -567,7 +567,8 @@ extern int compat_ipv6_getsockopt(struct sock *sk,
extern int ip6_datagram_connect(struct sock *sk,
struct sockaddr *addr, int addr_len);

-extern int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len);
+extern int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
+ int *addr_len);
extern void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
u32 info, u8 *payload);
extern void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info);
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 099e6c3..d5a179b 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -356,7 +356,7 @@ void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 inf
/*
* 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;
@@ -393,6 +393,7 @@ int ip_recv_error(struct sock *sk, struct msghdr *msg, int len)
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/raw.c b/net/ipv4/raw.c
index c50344b..8065efa 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -682,7 +682,7 @@ static int raw_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
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 80487ee..a9aed7e 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -942,7 +942,7 @@ int udp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
int is_udplite = IS_UDPLITE(sk);

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 e2bdc6d..ef6436d 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -281,7 +281,7 @@ void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info)
/*
* 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;
@@ -333,6 +333,7 @@ int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
htonl(0xffff),
*(__be32 *)(nh + serr->addr_offset));
}
+ *addr_len = sizeof(*sin);
}

memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index df75f94..d5b09c7 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -457,7 +457,7 @@ static int rawv6_recvmsg(struct kiocb *iocb, struct sock *sk,
return -EOPNOTSUPP;

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)
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index ce291af..3a91859 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -201,7 +201,7 @@ int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
int is_udp4;

if (flags & MSG_ERRQUEUE)
- return ipv6_recv_error(sk, msg, len);
+ return ipv6_recv_error(sk, msg, len, addr_len);

try_again:
skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
--
1.7.12.2.21.g234cd45.dirty