This is a note to let you know that I've just added the patch titled
inet: prevent leakage of uninitialized memory to user in recv syscalls
to the 3.12-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
inet-prevent-leakage-of-uninitialized-memory-to-user-in-recv-syscalls.patch
and it can be found in the queue-3.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Thu Dec 5 16:16:39 PST 2013
From: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx>
Date: Mon, 18 Nov 2013 04:20:45 +0100
Subject: inet: prevent leakage of uninitialized memory to user in recv syscalls
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 | 19 +++++++------------
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, 17 insertions(+), 38 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
@@ -827,8 +827,6 @@ int ping_recvmsg(struct kiocb *iocb, str
{
struct inet_sock *isk = inet_sk(sk);
int family = sk->sk_family;
- struct sockaddr_in *sin;
- struct sockaddr_in6 *sin6;
struct sk_buff *skb;
int copied, err;
@@ -838,13 +836,6 @@ int ping_recvmsg(struct kiocb *iocb, str
if (flags & MSG_OOB)
goto out;
- if (addr_len) {
- if (family == AF_INET)
- *addr_len = sizeof(*sin);
- else if (family == AF_INET6 && addr_len)
- *addr_len = sizeof(*sin6);
- }
-
if (flags & MSG_ERRQUEUE) {
if (family == AF_INET) {
return ip_recv_error(sk, msg, len);
@@ -874,11 +865,13 @@ int ping_recvmsg(struct kiocb *iocb, str
/* Copy the address and add cmsg data. */
if (family == AF_INET) {
- sin = (struct sockaddr_in *) 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);
@@ -887,17 +880,19 @@ int ping_recvmsg(struct kiocb *iocb, str
} else if (family == AF_INET6) {
struct ipv6_pinfo *np = inet6_sk(sk);
struct ipv6hdr *ip6 = ipv6_hdr(skb);
- sin6 = (struct sockaddr_in6 *) msg->msg_name;
+ struct sockaddr_in6 *sin6 =
+ (struct sockaddr_in6 *)msg->msg_name;
+
sin6->sin6_family = AF_INET6;
sin6->sin6_port = 0;
sin6->sin6_addr = ip6->saddr;
-
sin6->sin6_flowinfo = 0;
if (np->sndflow)
sin6->sin6_flowinfo = ip6_flowinfo(ip6);
sin6->sin6_scope_id = ipv6_iface_scope_id(&sin6->sin6_addr,
IP6CB(skb)->iif);
+ *addr_len = sizeof(*sin6);
if (inet6_sk(sk)->rxopt.all)
pingv6_ops.ip6_datagram_recv_ctl(sk, msg, skb);
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -694,9 +694,6 @@ 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;
@@ -724,6 +721,7 @@ 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
@@ -1209,12 +1209,6 @@ 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);
@@ -1276,6 +1270,7 @@ 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
@@ -466,9 +466,6 @@ 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);
@@ -507,6 +504,7 @@ 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
@@ -374,9 +374,6 @@ 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);
@@ -462,7 +459,7 @@ 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);
Patches currently in stable-queue which might be from hannes@xxxxxxxxxxxxxxxxxxx are
queue-3.12/ipv6-fix-inet6_init-cleanup-order.patch
queue-3.12/ipv6-fix-headroom-calculation-in-udp6_ufo_fragment.patch
queue-3.12/ping-prevent-null-pointer-dereference-on-write-to-msg_name.patch
queue-3.12/inet-prevent-leakage-of-uninitialized-memory-to-user-in-recv-syscalls.patch
queue-3.12/net-rework-recvmsg-handler-msg_name-and-msg_namelen-logic.patch
queue-3.12/ipv6-fix-possible-seqlock-deadlock-in-ip6_finish_output2.patch
queue-3.12/net-add-bug_on-if-kernel-advertises-msg_namelen-sizeof-struct-sockaddr_storage.patch
queue-3.12/ipv6-use-rt6_get_dflt_router-to-get-default-router-in.patch
queue-3.12/random32-fix-off-by-one-in-seeding-requirement.patch
queue-3.12/inet-fix-possible-seqlock-deadlocks.patch
queue-3.12/inet-fix-addr_len-msg-msg_namelen-assignment-in-recv_error-and-rxpmtu-functions.patch
queue-3.12/ipv6-protect-for_each_sk_fl_rcu-in-mem_check-with.patch
queue-3.12/ipv6-fix-leaking-uninitialized-port-number-of-offender-sockaddr.patch
--
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