[PATCH 3.10 18/58] inet: prevent leakage of uninitialized memory to user in recv syscalls
From: Greg Kroah-Hartman
Date: Fri Dec 06 2013 - 17:15:05 EST
3.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx>
[ Upstream commit bceaa90240b6019ed73b49965eac7d167610be69 ]
Only update *addr_len when we actually fill in sockaddr, otherwise we
can return uninitialized memory from the stack to the caller in the
recvfrom, recvmmsg and recvmsg syscalls. Drop the the (addr_len == NULL)
checks because we only get called with a valid addr_len pointer either
from sock_common_recvmsg or inet_recvmsg.
If a blocking read waits on a socket which is concurrently shut down we
now return zero and set msg_msgnamelen to 0.
Reported-by: mpb <mpb.mail@xxxxxxxxx>
Suggested-by: Eric Dumazet <eric.dumazet@xxxxxxxxx>
Signed-off-by: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ieee802154/dgram.c | 3 +--
net/ipv4/ping.c | 9 ++++-----
net/ipv4/raw.c | 4 +---
net/ipv4/udp.c | 7 +------
net/ipv6/raw.c | 4 +---
net/ipv6/udp.c | 5 +----
net/l2tp/l2tp_ip.c | 4 +---
net/phonet/datagram.c | 9 ++++-----
8 files changed, 14 insertions(+), 31 deletions(-)
--- a/net/ieee802154/dgram.c
+++ b/net/ieee802154/dgram.c
@@ -315,9 +315,8 @@ static int dgram_recvmsg(struct kiocb *i
if (saddr) {
saddr->family = AF_IEEE802154;
saddr->addr = mac_cb(skb)->sa;
- }
- if (addr_len)
*addr_len = sizeof(*saddr);
+ }
if (flags & MSG_TRUNC)
copied = skb->len;
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -626,7 +626,6 @@ static int ping_recvmsg(struct kiocb *io
size_t len, int noblock, int flags, int *addr_len)
{
struct inet_sock *isk = inet_sk(sk);
- struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
struct sk_buff *skb;
int copied, err;
@@ -636,9 +635,6 @@ static int ping_recvmsg(struct kiocb *io
if (flags & MSG_OOB)
goto out;
- if (addr_len)
- *addr_len = sizeof(*sin);
-
if (flags & MSG_ERRQUEUE)
return ip_recv_error(sk, msg, len);
@@ -660,11 +656,14 @@ static int ping_recvmsg(struct kiocb *io
sock_recv_timestamp(msg, sk, skb);
/* Copy the address. */
- if (sin) {
+ if (msg->msg_name) {
+ struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
+
sin->sin_family = AF_INET;
sin->sin_port = 0 /* skb->h.uh->source */;
sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
+ *addr_len = sizeof(*sin);
}
if (isk->cmsg_flags)
ip_cmsg_recv(msg, skb);
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -692,9 +692,6 @@ static int raw_recvmsg(struct kiocb *ioc
if (flags & MSG_OOB)
goto out;
- if (addr_len)
- *addr_len = sizeof(*sin);
-
if (flags & MSG_ERRQUEUE) {
err = ip_recv_error(sk, msg, len);
goto out;
@@ -722,6 +719,7 @@ static int raw_recvmsg(struct kiocb *ioc
sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
sin->sin_port = 0;
memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
+ *addr_len = sizeof(*sin);
}
if (inet->cmsg_flags)
ip_cmsg_recv(msg, skb);
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1207,12 +1207,6 @@ int udp_recvmsg(struct kiocb *iocb, stru
int is_udplite = IS_UDPLITE(sk);
bool slow;
- /*
- * Check any passed addresses
- */
- if (addr_len)
- *addr_len = sizeof(*sin);
-
if (flags & MSG_ERRQUEUE)
return ip_recv_error(sk, msg, len);
@@ -1274,6 +1268,7 @@ try_again:
sin->sin_port = udp_hdr(skb)->source;
sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
+ *addr_len = sizeof(*sin);
}
if (inet->cmsg_flags)
ip_cmsg_recv(msg, skb);
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -459,9 +459,6 @@ static int rawv6_recvmsg(struct kiocb *i
if (flags & MSG_OOB)
return -EOPNOTSUPP;
- if (addr_len)
- *addr_len=sizeof(*sin6);
-
if (flags & MSG_ERRQUEUE)
return ipv6_recv_error(sk, msg, len);
@@ -500,6 +497,7 @@ static int rawv6_recvmsg(struct kiocb *i
sin6->sin6_flowinfo = 0;
sin6->sin6_scope_id = ipv6_iface_scope_id(&sin6->sin6_addr,
IP6CB(skb)->iif);
+ *addr_len = sizeof(*sin6);
}
sock_recv_ts_and_drops(msg, sk, skb);
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -373,9 +373,6 @@ int udpv6_recvmsg(struct kiocb *iocb, st
int is_udp4;
bool slow;
- if (addr_len)
- *addr_len = sizeof(struct sockaddr_in6);
-
if (flags & MSG_ERRQUEUE)
return ipv6_recv_error(sk, msg, len);
@@ -461,7 +458,7 @@ try_again:
ipv6_iface_scope_id(&sin6->sin6_addr,
IP6CB(skb)->iif);
}
-
+ *addr_len = sizeof(*sin6);
}
if (is_udp4) {
if (inet->cmsg_flags)
--- a/net/l2tp/l2tp_ip.c
+++ b/net/l2tp/l2tp_ip.c
@@ -518,9 +518,6 @@ static int l2tp_ip_recvmsg(struct kiocb
if (flags & MSG_OOB)
goto out;
- if (addr_len)
- *addr_len = sizeof(*sin);
-
skb = skb_recv_datagram(sk, flags, noblock, &err);
if (!skb)
goto out;
@@ -543,6 +540,7 @@ static int l2tp_ip_recvmsg(struct kiocb
sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
sin->sin_port = 0;
memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
+ *addr_len = sizeof(*sin);
}
if (inet->cmsg_flags)
ip_cmsg_recv(msg, skb);
--- a/net/phonet/datagram.c
+++ b/net/phonet/datagram.c
@@ -139,9 +139,6 @@ static int pn_recvmsg(struct kiocb *iocb
MSG_CMSG_COMPAT))
goto out_nofree;
- if (addr_len)
- *addr_len = sizeof(sa);
-
skb = skb_recv_datagram(sk, flags, noblock, &rval);
if (skb == NULL)
goto out_nofree;
@@ -162,8 +159,10 @@ static int pn_recvmsg(struct kiocb *iocb
rval = (flags & MSG_TRUNC) ? skb->len : copylen;
- if (msg->msg_name != NULL)
- memcpy(msg->msg_name, &sa, sizeof(struct sockaddr_pn));
+ if (msg->msg_name != NULL) {
+ memcpy(msg->msg_name, &sa, sizeof(sa));
+ *addr_len = sizeof(sa);
+ }
out:
skb_free_datagram(sk, skb);
--
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