From 4440a2ab3b9f40dddbe006331ef0659c76859296 Mon Sep 17 00:00:00 2001 From: Gao Feng Date: Tue, 13 Sep 2016 08:49:18 +0800 Subject: netfilter: synproxy: Check oom when adding synproxy and seqadj ct extensions When memory is exhausted, nfct_seqadj_ext_add may fail to add the synproxy and seqadj extensions. The function nf_ct_seqadj_init doesn't check if get valid seqadj pointer by the nfct_seqadj. Now drop the packet directly when fail to add seqadj extension to avoid dereference NULL pointer in nf_ct_seqadj_init from init_conntrack(). Signed-off-by: Gao Feng Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/nf_conntrack_synproxy.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'include') diff --git a/include/net/netfilter/nf_conntrack_synproxy.h b/include/net/netfilter/nf_conntrack_synproxy.h index 6793614e6502..e6937318546c 100644 --- a/include/net/netfilter/nf_conntrack_synproxy.h +++ b/include/net/netfilter/nf_conntrack_synproxy.h @@ -27,6 +27,20 @@ static inline struct nf_conn_synproxy *nfct_synproxy_ext_add(struct nf_conn *ct) #endif } +static inline bool nf_ct_add_synproxy(struct nf_conn *ct, + const struct nf_conn *tmpl) +{ + if (tmpl && nfct_synproxy(tmpl)) { + if (!nfct_seqadj_ext_add(ct)) + return false; + + if (!nfct_synproxy_ext_add(ct)) + return false; + } + + return true; +} + struct synproxy_stats { unsigned int syn_received; unsigned int cookie_invalid; -- cgit v1.2.3 From 20c64d5cd5a2bdcdc8982a06cb05e5e1bd851a3d Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 15 Sep 2016 08:48:46 -0700 Subject: net: avoid sk_forward_alloc overflows A malicious TCP receiver, sending SACK, can force the sender to split skbs in write queue and increase its memory usage. Then, when socket is closed and its write queue purged, we might overflow sk_forward_alloc (It becomes negative) sk_mem_reclaim() does nothing in this case, and more than 2GB are leaked from TCP perspective (tcp_memory_allocated is not changed) Then warnings trigger from inet_sock_destruct() and sk_stream_kill_queues() seeing a not zero sk_forward_alloc All TCP stack can be stuck because TCP is under memory pressure. A simple fix is to preemptively reclaim from sk_mem_uncharge(). This makes sure a socket wont have more than 2 MB forward allocated, after burst and idle period. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/sock.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'include') diff --git a/include/net/sock.h b/include/net/sock.h index ff5be7e8ddea..8741988e6880 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1332,6 +1332,16 @@ static inline void sk_mem_uncharge(struct sock *sk, int size) if (!sk_has_account(sk)) return; sk->sk_forward_alloc += size; + + /* Avoid a possible overflow. + * TCP send queues can make this happen, if sk_mem_reclaim() + * is not called and more than 2 GBytes are released at once. + * + * If we reach 2 MBytes, reclaim 1 MBytes right now, there is + * no need to hold that much forward allocation anyway. + */ + if (unlikely(sk->sk_forward_alloc >= 1 << 21)) + __sk_mem_reclaim(sk, 1 << 20); } static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb) -- cgit v1.2.3 From 4496195ddd75c4ad57b783739414e69b7d79843e Mon Sep 17 00:00:00 2001 From: Marcelo Ricardo Leitner Date: Thu, 15 Sep 2016 15:02:38 -0300 Subject: sctp: fix SSN comparision This function actually operates on u32 yet its paramteres were declared as u16, causing integer truncation upon calling. Note in patch context that ADDIP_SERIAL_SIGN_BIT is already 32 bits. Signed-off-by: Marcelo Ricardo Leitner Acked-by: Neil Horman Signed-off-by: David S. Miller --- include/net/sctp/sm.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/net/sctp/sm.h b/include/net/sctp/sm.h index efc01743b9d6..bafe2a0ab908 100644 --- a/include/net/sctp/sm.h +++ b/include/net/sctp/sm.h @@ -382,7 +382,7 @@ enum { ADDIP_SERIAL_SIGN_BIT = (1<<31) }; -static inline int ADDIP_SERIAL_gte(__u16 s, __u16 t) +static inline int ADDIP_SERIAL_gte(__u32 s, __u32 t) { return ((s) == (t)) || (((t) - (s)) & ADDIP_SERIAL_SIGN_BIT); } -- cgit v1.2.3 From 63c43787d35e45562a6b5927e2edc8f4783d95b8 Mon Sep 17 00:00:00 2001 From: Nicolas Dichtel Date: Mon, 19 Sep 2016 16:17:57 +0200 Subject: vti6: fix input path Since commit 1625f4529957, vti6 is broken, all input packets are dropped (LINUX_MIB_XFRMINNOSTATES is incremented). XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 is set by vti6_rcv() before calling xfrm6_rcv()/xfrm6_rcv_spi(), thus we cannot set to NULL that value in xfrm6_rcv_spi(). A new function xfrm6_rcv_tnl() that enables to pass a value to xfrm6_rcv_spi() is added, so that xfrm6_rcv() is not touched (this function is used in several handlers). CC: Alexey Kodanev Fixes: 1625f4529957 ("net/xfrm_input: fix possible NULL deref of tunnel.ip6->parms.i_key") Signed-off-by: Nicolas Dichtel Signed-off-by: Steffen Klassert --- include/net/xfrm.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/net/xfrm.h b/include/net/xfrm.h index adfebd6f243c..17934312eecb 100644 --- a/include/net/xfrm.h +++ b/include/net/xfrm.h @@ -1540,8 +1540,10 @@ int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler, unsigned short family); void xfrm4_local_error(struct sk_buff *skb, u32 mtu); int xfrm6_extract_header(struct sk_buff *skb); int xfrm6_extract_input(struct xfrm_state *x, struct sk_buff *skb); -int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi); +int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi, + struct ip6_tnl *t); int xfrm6_transport_finish(struct sk_buff *skb, int async); +int xfrm6_rcv_tnl(struct sk_buff *skb, struct ip6_tnl *t); int xfrm6_rcv(struct sk_buff *skb); int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr, xfrm_address_t *saddr, u8 proto); -- cgit v1.2.3