From d71b7896886345c53ef1d84bda2bc758554f5d61 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 3 Feb 2017 00:03:26 -0800 Subject: netlabel: out of bound access in cipso_v4_validate() syzkaller found another out of bound access in ip_options_compile(), or more exactly in cipso_v4_validate() Fixes: 20e2a8648596 ("cipso: handle CIPSO options correctly when NetLabel is disabled") Fixes: 446fda4f2682 ("[NetLabel]: CIPSOv4 engine") Signed-off-by: Eric Dumazet Reported-by: Dmitry Vyukov Cc: Paul Moore Acked-by: Paul Moore Signed-off-by: David S. Miller --- include/net/cipso_ipv4.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/net') diff --git a/include/net/cipso_ipv4.h b/include/net/cipso_ipv4.h index 3ebb168b9afc..a34b141f125f 100644 --- a/include/net/cipso_ipv4.h +++ b/include/net/cipso_ipv4.h @@ -309,6 +309,10 @@ static inline int cipso_v4_validate(const struct sk_buff *skb, } for (opt_iter = 6; opt_iter < opt_len;) { + if (opt_iter + 1 == opt_len) { + err_offset = opt_iter; + goto out; + } tag_len = opt[opt_iter + 1]; if ((tag_len == 0) || (tag_len > (opt_len - opt_iter))) { err_offset = opt_iter + 1; -- cgit v1.2.3 From 69629464e0b587f3711739b3aa2bcdaf2e075276 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sun, 5 Feb 2017 09:25:24 -0800 Subject: udp: properly cope with csum errors Dmitry reported that UDP sockets being destroyed would trigger the WARN_ON(atomic_read(&sk->sk_rmem_alloc)); in inet_sock_destruct() It turns out we do not properly destroy skb(s) that have wrong UDP checksum. Thanks again to syzkaller team. Fixes : 7c13f97ffde6 ("udp: do fwd memory scheduling on dequeue") Reported-by: Dmitry Vyukov Signed-off-by: Eric Dumazet Cc: Paolo Abeni Cc: Hannes Frederic Sowa Acked-by: Paolo Abeni Signed-off-by: David S. Miller --- include/net/sock.h | 4 +++- net/core/datagram.c | 8 ++++++-- net/ipv4/udp.c | 2 +- net/ipv6/udp.c | 2 +- 4 files changed, 11 insertions(+), 5 deletions(-) (limited to 'include/net') diff --git a/include/net/sock.h b/include/net/sock.h index f0e867f58722..c4f5e6fca17c 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -2006,7 +2006,9 @@ void sk_reset_timer(struct sock *sk, struct timer_list *timer, void sk_stop_timer(struct sock *sk, struct timer_list *timer); int __sk_queue_drop_skb(struct sock *sk, struct sk_buff *skb, - unsigned int flags); + unsigned int flags, + void (*destructor)(struct sock *sk, + struct sk_buff *skb)); int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); diff --git a/net/core/datagram.c b/net/core/datagram.c index 662bea587165..ea633342ab0d 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -332,7 +332,9 @@ void __skb_free_datagram_locked(struct sock *sk, struct sk_buff *skb, int len) EXPORT_SYMBOL(__skb_free_datagram_locked); int __sk_queue_drop_skb(struct sock *sk, struct sk_buff *skb, - unsigned int flags) + unsigned int flags, + void (*destructor)(struct sock *sk, + struct sk_buff *skb)) { int err = 0; @@ -342,6 +344,8 @@ int __sk_queue_drop_skb(struct sock *sk, struct sk_buff *skb, if (skb == skb_peek(&sk->sk_receive_queue)) { __skb_unlink(skb, &sk->sk_receive_queue); atomic_dec(&skb->users); + if (destructor) + destructor(sk, skb); err = 0; } spin_unlock_bh(&sk->sk_receive_queue.lock); @@ -375,7 +379,7 @@ EXPORT_SYMBOL(__sk_queue_drop_skb); int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int flags) { - int err = __sk_queue_drop_skb(sk, skb, flags); + int err = __sk_queue_drop_skb(sk, skb, flags, NULL); kfree_skb(skb); sk_mem_reclaim_partial(sk); diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 1307a7c2e544..8aab7d78d25b 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1501,7 +1501,7 @@ try_again: return err; csum_copy_err: - if (!__sk_queue_drop_skb(sk, skb, flags)) { + if (!__sk_queue_drop_skb(sk, skb, flags, udp_skb_destructor)) { UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite); UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite); } diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 4d5c4eee4b3f..8990856f5101 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -441,7 +441,7 @@ try_again: return err; csum_copy_err: - if (!__sk_queue_drop_skb(sk, skb, flags)) { + if (!__sk_queue_drop_skb(sk, skb, flags, udp_skb_destructor)) { if (is_udp4) { UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite); -- cgit v1.2.3 From 2bd137de531367fb573d90150d1872cb2a2095f7 Mon Sep 17 00:00:00 2001 From: David Ahern Date: Wed, 8 Feb 2017 09:29:00 -0800 Subject: lwtunnel: valid encap attr check should return 0 when lwtunnel is disabled An error was reported upgrading to 4.9.8: root@Typhoon:~# ip route add default table 210 nexthop dev eth0 via 10.68.64.1 weight 1 nexthop dev eth0 via 10.68.64.2 weight 1 RTNETLINK answers: Operation not supported The problem occurs when CONFIG_LWTUNNEL is not enabled and a multipath route is submitted. The point of lwtunnel_valid_encap_type_attr is catch modules that need to be loaded before any references are taken with rntl held. With CONFIG_LWTUNNEL disabled, there will be no modules to load so the lwtunnel_valid_encap_type_attr stub should just return 0. Fixes: 9ed59592e3e3 ("lwtunnel: fix autoload of lwt modules") Reported-by: pupilla@libero.it Signed-off-by: David Ahern Signed-off-by: David S. Miller --- include/net/lwtunnel.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'include/net') diff --git a/include/net/lwtunnel.h b/include/net/lwtunnel.h index 73dd87647460..0388b9c5f5e2 100644 --- a/include/net/lwtunnel.h +++ b/include/net/lwtunnel.h @@ -178,7 +178,10 @@ static inline int lwtunnel_valid_encap_type(u16 encap_type) } static inline int lwtunnel_valid_encap_type_attr(struct nlattr *attr, int len) { - return -EOPNOTSUPP; + /* return 0 since we are not walking attr looking for + * RTA_ENCAP_TYPE attribute on nexthops. + */ + return 0; } static inline int lwtunnel_build_state(struct net_device *dev, u16 encap_type, -- cgit v1.2.3