From patchwork Wed Dec 11 14:16:23 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Henriques X-Patchwork-Id: 300095 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 427AD2C00A4 for ; Thu, 12 Dec 2013 01:16:43 +1100 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1Vqkac-0004bK-Ao; Wed, 11 Dec 2013 14:16:38 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1VqkaR-0004Zc-MV for kernel-team@lists.ubuntu.com; Wed, 11 Dec 2013 14:16:27 +0000 Received: from bl15-242-146.dsl.telepac.pt ([188.80.242.146] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1VqkaR-0007g3-BM for kernel-team@lists.ubuntu.com; Wed, 11 Dec 2013 14:16:27 +0000 From: Luis Henriques To: kernel-team@lists.ubuntu.com Subject: [CVE-2013-6405][Lucid][PATCH 1/2] inet: prevent leakage of uninitialized memory to user in recv syscalls Date: Wed, 11 Dec 2013 14:16:23 +0000 Message-Id: <1386771384-781-2-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1386771384-781-1-git-send-email-luis.henriques@canonical.com> References: <1386771384-781-1-git-send-email-luis.henriques@canonical.com> X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com From: Hannes Frederic Sowa CVE-2013-6405 BugLink: http://bugs.launchpad.net/bugs/1256919 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 Suggested-by: Eric Dumazet Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller (back ported from commit bceaa90240b6019ed73b49965eac7d167610be69) [ luis: dropped changes to: - net/ieee802154/dgram.c - net/ipv4/ping.c - net/l2tp/l2tp_ip.c ] Signed-off-by: Luis Henriques --- net/ipv4/raw.c | 4 +--- net/ipv4/udp.c | 7 +------ net/ipv6/raw.c | 4 +--- net/ipv6/udp.c | 5 +---- net/phonet/datagram.c | 9 ++++----- 5 files changed, 8 insertions(+), 21 deletions(-) diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index 07ab583..c50344b 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -681,9 +681,6 @@ static int raw_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, 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; @@ -711,6 +708,7 @@ static int raw_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, 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); diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 1357cee..0683693 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -942,12 +942,6 @@ int udp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, int err; int is_udplite = IS_UDPLITE(sk); - /* - * Check any passed addresses - */ - if (addr_len) - *addr_len = sizeof(*sin); - if (flags & MSG_ERRQUEUE) return ip_recv_error(sk, msg, len); @@ -1002,6 +996,7 @@ 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); diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index 4f24570..df75f94 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -456,9 +456,6 @@ static int rawv6_recvmsg(struct kiocb *iocb, struct sock *sk, if (flags & MSG_OOB) return -EOPNOTSUPP; - if (addr_len) - *addr_len=sizeof(*sin6); - if (flags & MSG_ERRQUEUE) return ipv6_recv_error(sk, msg, len); @@ -495,6 +492,7 @@ static int rawv6_recvmsg(struct kiocb *iocb, struct sock *sk, sin6->sin6_scope_id = 0; if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) sin6->sin6_scope_id = IP6CB(skb)->iif; + *addr_len = sizeof(*sin6); } sock_recv_timestamp(msg, sk, skb); diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index e0059e8..7495894 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -200,9 +200,6 @@ int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk, int is_udplite = IS_UDPLITE(sk); int is_udp4; - if (addr_len) - *addr_len=sizeof(struct sockaddr_in6); - if (flags & MSG_ERRQUEUE) return ipv6_recv_error(sk, msg, len); @@ -273,7 +270,7 @@ try_again: if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) sin6->sin6_scope_id = IP6CB(skb)->iif; } - + *addr_len = sizeof(*sin6); } if (is_udp4) { if (inet->cmsg_flags) diff --git a/net/phonet/datagram.c b/net/phonet/datagram.c index ef5c75c..c88da73 100644 --- a/net/phonet/datagram.c +++ b/net/phonet/datagram.c @@ -122,9 +122,6 @@ static int pn_recvmsg(struct kiocb *iocb, struct sock *sk, if (flags & MSG_OOB) goto out_nofree; - if (addr_len) - *addr_len = sizeof(sa); - skb = skb_recv_datagram(sk, flags, noblock, &rval); if (skb == NULL) goto out_nofree; @@ -145,8 +142,10 @@ static int pn_recvmsg(struct kiocb *iocb, struct sock *sk, 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);