From 013e8167899d389075160412a8c0c5e0581e1f13 Mon Sep 17 00:00:00 2001 From: David Lebrun Date: Thu, 2 Feb 2017 11:29:38 +0100 Subject: ipv6: sr: remove cleanup flag and fix HMAC computation In the latest version of the IPv6 Segment Routing IETF draft [1] the cleanup flag is removed and the flags field length is shrunk from 16 bits to 8 bits. As a consequence, the input of the HMAC computation is modified in a non-backward compatible way by covering the whole octet of flags instead of only the cleanup bit. As such, if an implementation compatible with the latest draft computes the HMAC of an SRH who has other flags set to 1, then the HMAC result would differ from the current implementation. This patch carries those modifications to prevent conflict with other implementations of IPv6 SR. [1] https://tools.ietf.org/html/draft-ietf-6man-segment-routing-header-05 Signed-off-by: David Lebrun Signed-off-by: David S. Miller --- include/uapi/linux/seg6.h | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/uapi/linux/seg6.h b/include/uapi/linux/seg6.h index c396a8052f73..052799e4d751 100644 --- a/include/uapi/linux/seg6.h +++ b/include/uapi/linux/seg6.h @@ -23,14 +23,12 @@ struct ipv6_sr_hdr { __u8 type; __u8 segments_left; __u8 first_segment; - __u8 flag_1; - __u8 flag_2; - __u8 reserved; + __u8 flags; + __u16 reserved; struct in6_addr segments[0]; }; -#define SR6_FLAG1_CLEANUP (1 << 7) #define SR6_FLAG1_PROTECTED (1 << 6) #define SR6_FLAG1_OAM (1 << 5) #define SR6_FLAG1_ALERT (1 << 4) @@ -42,8 +40,7 @@ struct ipv6_sr_hdr { #define SR6_TLV_PADDING 4 #define SR6_TLV_HMAC 5 -#define sr_has_cleanup(srh) ((srh)->flag_1 & SR6_FLAG1_CLEANUP) -#define sr_has_hmac(srh) ((srh)->flag_1 & SR6_FLAG1_HMAC) +#define sr_has_hmac(srh) ((srh)->flags & SR6_FLAG1_HMAC) struct sr6_tlv { __u8 type; -- cgit v1.2.3 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 ++++ net/ipv4/cipso_ipv4.c | 4 ++++ 2 files changed, 8 insertions(+) (limited to 'include') 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; diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c index 72d6f056d863..ae206163c273 100644 --- a/net/ipv4/cipso_ipv4.c +++ b/net/ipv4/cipso_ipv4.c @@ -1587,6 +1587,10 @@ int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option) goto validate_return_locked; } + if (opt_iter + 1 == opt_len) { + err_offset = opt_iter; + goto validate_return_locked; + } tag_len = tag[1]; if (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') 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