From 175fba16aa9ed2175367117b3e497295b1ae6fc6 Mon Sep 17 00:00:00 2001 From: Nelson Elhage Date: Wed, 3 Nov 2010 16:35:41 +0000 Subject: [PATCH] inet_diag: Make sure we actually run the same bytecode we audited, CVE-2010-3880 BugLink: http://bugs.launchpad.net/bugs/711865 CVE-2010-3880 We were using nlmsg_find_attr() to look up the bytecode by attribute when auditing, but then just using the first attribute when actually running bytecode. So, if we received a message with two attribute elements, where only the second had type INET_DIAG_REQ_BYTECODE, we would validate and run different bytecode strings. Fix this by consistently using nlmsg_find_attr everywhere. Signed-off-by: Nelson Elhage Signed-off-by: Thomas Graf Signed-off-by: David S. Miller (back ported from commit 22e76c849d505d87c5ecf3d3e6742a65f0ff4860) Acked-by: Stefan Bader Acked-by: Brad Figg Signed-off-by: Tim Gardner --- include/net/netlink.h | 2 +- net/ipv4/inet_diag.c | 27 ++++++++++++++++----------- 2 files changed, 17 insertions(+), 12 deletions(-) diff --git a/include/net/netlink.h b/include/net/netlink.h index a63b219..c344646 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -384,7 +384,7 @@ static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen, * * Returns the first attribute which matches the specified type. */ -static inline struct nlattr *nlmsg_find_attr(struct nlmsghdr *nlh, +static inline struct nlattr *nlmsg_find_attr(const struct nlmsghdr *nlh, int hdrlen, int attrtype) { return nla_find(nlmsg_attrdata(nlh, hdrlen), diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c index a706a47..6fe360f 100644 --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -489,9 +489,11 @@ static int inet_csk_diag_dump(struct sock *sk, { struct inet_diag_req *r = NLMSG_DATA(cb->nlh); - if (cb->nlh->nlmsg_len > 4 + NLMSG_SPACE(sizeof(*r))) { + if (nlmsg_attrlen(cb->nlh, sizeof(*r))) { struct inet_diag_entry entry; - struct rtattr *bc = (struct rtattr *)(r + 1); + const struct nlattr *bc = nlmsg_find_attr(cb->nlh, + sizeof(*r), + INET_DIAG_REQ_BYTECODE); struct inet_sock *inet = inet_sk(sk); entry.family = sk->sk_family; @@ -511,7 +513,7 @@ static int inet_csk_diag_dump(struct sock *sk, entry.dport = ntohs(inet->dport); entry.userlocks = sk->sk_userlocks; - if (!inet_diag_bc_run(RTA_DATA(bc), RTA_PAYLOAD(bc), &entry)) + if (!inet_diag_bc_run(nla_data(bc), nla_len(bc), &entry)) return 0; } @@ -526,9 +528,11 @@ static int inet_twsk_diag_dump(struct inet_timewait_sock *tw, { struct inet_diag_req *r = NLMSG_DATA(cb->nlh); - if (cb->nlh->nlmsg_len > 4 + NLMSG_SPACE(sizeof(*r))) { + if (nlmsg_attrlen(cb->nlh, sizeof(*r))) { struct inet_diag_entry entry; - struct rtattr *bc = (struct rtattr *)(r + 1); + const struct nlattr *bc = nlmsg_find_attr(cb->nlh, + sizeof(*r), + INET_DIAG_REQ_BYTECODE); entry.family = tw->tw_family; #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE) @@ -547,7 +551,7 @@ static int inet_twsk_diag_dump(struct inet_timewait_sock *tw, entry.dport = ntohs(tw->tw_dport); entry.userlocks = 0; - if (!inet_diag_bc_run(RTA_DATA(bc), RTA_PAYLOAD(bc), &entry)) + if (!inet_diag_bc_run(nla_data(bc), nla_len(bc), &entry)) return 0; } @@ -617,7 +621,7 @@ static int inet_diag_dump_reqs(struct sk_buff *skb, struct sock *sk, struct inet_diag_req *r = NLMSG_DATA(cb->nlh); struct inet_connection_sock *icsk = inet_csk(sk); struct listen_sock *lopt; - struct rtattr *bc = NULL; + const struct nlattr *bc = NULL; struct inet_sock *inet = inet_sk(sk); int j, s_j; int reqnum, s_reqnum; @@ -637,8 +641,9 @@ static int inet_diag_dump_reqs(struct sk_buff *skb, struct sock *sk, if (!lopt || !lopt->qlen) goto out; - if (cb->nlh->nlmsg_len > 4 + NLMSG_SPACE(sizeof(*r))) { - bc = (struct rtattr *)(r + 1); + if (nlmsg_attrlen(cb->nlh, sizeof(*r))) { + bc = nlmsg_find_attr(cb->nlh, sizeof(*r), + INET_DIAG_REQ_BYTECODE); entry.sport = inet->num; entry.userlocks = sk->sk_userlocks; } @@ -671,8 +676,8 @@ static int inet_diag_dump_reqs(struct sk_buff *skb, struct sock *sk, &ireq->rmt_addr; entry.dport = ntohs(ireq->rmt_port); - if (!inet_diag_bc_run(RTA_DATA(bc), - RTA_PAYLOAD(bc), &entry)) + if (!inet_diag_bc_run(nla_data(bc), + nla_len(bc), &entry)) continue; } -- 1.7.0.4