From bfc0698bebcb16d19ecfc89574ad4d696955e5d3 Mon Sep 17 00:00:00 2001 From: Sowmini Varadhan Date: Mon, 3 Sep 2018 04:36:52 -0700 Subject: xfrm: reset transport header back to network header after all input transforms ahave been applied A policy may have been set up with multiple transforms (e.g., ESP and ipcomp). In this situation, the ingress IPsec processing iterates in xfrm_input() and applies each transform in turn, processing the nexthdr to find any additional xfrm that may apply. This patch resets the transport header back to network header only after the last transformation so that subsequent xfrms can find the correct transport header. Fixes: 7785bba299a8 ("esp: Add a software GRO codepath") Suggested-by: Steffen Klassert Signed-off-by: Sowmini Varadhan Signed-off-by: Steffen Klassert --- net/ipv4/xfrm4_input.c | 1 + net/ipv4/xfrm4_mode_transport.c | 4 +--- 2 files changed, 2 insertions(+), 3 deletions(-) (limited to 'net/ipv4') diff --git a/net/ipv4/xfrm4_input.c b/net/ipv4/xfrm4_input.c index bcfc00e88756..f8de2482a529 100644 --- a/net/ipv4/xfrm4_input.c +++ b/net/ipv4/xfrm4_input.c @@ -67,6 +67,7 @@ int xfrm4_transport_finish(struct sk_buff *skb, int async) if (xo && (xo->flags & XFRM_GRO)) { skb_mac_header_rebuild(skb); + skb_reset_transport_header(skb); return 0; } diff --git a/net/ipv4/xfrm4_mode_transport.c b/net/ipv4/xfrm4_mode_transport.c index 3d36644890bb..1ad2c2c4e250 100644 --- a/net/ipv4/xfrm4_mode_transport.c +++ b/net/ipv4/xfrm4_mode_transport.c @@ -46,7 +46,6 @@ static int xfrm4_transport_output(struct xfrm_state *x, struct sk_buff *skb) static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb) { int ihl = skb->data - skb_transport_header(skb); - struct xfrm_offload *xo = xfrm_offload(skb); if (skb->transport_header != skb->network_header) { memmove(skb_transport_header(skb), @@ -54,8 +53,7 @@ static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb) skb->network_header = skb->transport_header; } ip_hdr(skb)->tot_len = htons(skb->len + ihl); - if (!xo || !(xo->flags & XFRM_GRO)) - skb_reset_transport_header(skb); + skb_reset_transport_header(skb); return 0; } -- cgit v1.2.3 From d4ce58082f206bf6e7d697380c7bc5480a8b0264 Mon Sep 17 00:00:00 2001 From: Maciej Żenczykowski Date: Tue, 25 Sep 2018 21:59:28 -0700 Subject: net-tcp: /proc/sys/net/ipv4/tcp_probe_interval is a u32 not int MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit (fix documentation and sysctl access to treat it as such) Tested: # zcat /proc/config.gz | egrep ^CONFIG_HZ CONFIG_HZ_1000=y CONFIG_HZ=1000 # echo $[(1<<32)/1000 + 1] | tee /proc/sys/net/ipv4/tcp_probe_interval 4294968 tee: /proc/sys/net/ipv4/tcp_probe_interval: Invalid argument # echo $[(1<<32)/1000] | tee /proc/sys/net/ipv4/tcp_probe_interval 4294967 # echo 0 | tee /proc/sys/net/ipv4/tcp_probe_interval # echo -1 | tee /proc/sys/net/ipv4/tcp_probe_interval -1 tee: /proc/sys/net/ipv4/tcp_probe_interval: Invalid argument Signed-off-by: Maciej Żenczykowski Signed-off-by: David S. Miller --- Documentation/networking/ip-sysctl.txt | 2 +- net/ipv4/sysctl_net_ipv4.c | 6 ++++-- 2 files changed, 5 insertions(+), 3 deletions(-) (limited to 'net/ipv4') diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 8313a636dd53..960de8fe3f40 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -425,7 +425,7 @@ tcp_mtu_probing - INTEGER 1 - Disabled by default, enabled when an ICMP black hole detected 2 - Always enabled, use initial MSS of tcp_base_mss. -tcp_probe_interval - INTEGER +tcp_probe_interval - UNSIGNED INTEGER Controls how often to start TCP Packetization-Layer Path MTU Discovery reprobe. The default is reprobing every 10 minutes as per RFC4821. diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c index b92f422f2fa8..891ed2f91467 100644 --- a/net/ipv4/sysctl_net_ipv4.c +++ b/net/ipv4/sysctl_net_ipv4.c @@ -48,6 +48,7 @@ static int tcp_syn_retries_max = MAX_TCP_SYNCNT; static int ip_ping_group_range_min[] = { 0, 0 }; static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX }; static int comp_sack_nr_max = 255; +static u32 u32_max_div_HZ = UINT_MAX / HZ; /* obsolete */ static int sysctl_tcp_low_latency __read_mostly; @@ -745,9 +746,10 @@ static struct ctl_table ipv4_net_table[] = { { .procname = "tcp_probe_interval", .data = &init_net.ipv4.sysctl_tcp_probe_interval, - .maxlen = sizeof(int), + .maxlen = sizeof(u32), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_douintvec_minmax, + .extra2 = &u32_max_div_HZ, }, { .procname = "igmp_link_local_mcast_reports", -- cgit v1.2.3 From 1ad98e9d1bdf4724c0a8532fabd84bf3c457c2bc Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 1 Oct 2018 15:02:26 -0700 Subject: tcp/dccp: fix lockdep issue when SYN is backlogged In normal SYN processing, packets are handled without listener lock and in RCU protected ingress path. But syzkaller is known to be able to trick us and SYN packets might be processed in process context, after being queued into socket backlog. In commit 06f877d613be ("tcp/dccp: fix other lockdep splats accessing ireq_opt") I made a very stupid fix, that happened to work mostly because of the regular path being RCU protected. Really the thing protecting ireq->ireq_opt is RCU read lock, and the pseudo request refcnt is not relevant. This patch extends what I did in commit 449809a66c1d ("tcp/dccp: block BH for SYN processing") by adding an extra rcu_read_{lock|unlock} pair in the paths that might be taken when processing SYN from socket backlog (thus possibly in process context) Fixes: 06f877d613be ("tcp/dccp: fix other lockdep splats accessing ireq_opt") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller --- include/net/inet_sock.h | 3 +-- net/dccp/input.c | 4 +++- net/ipv4/tcp_input.c | 4 +++- 3 files changed, 7 insertions(+), 4 deletions(-) (limited to 'net/ipv4') diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h index e03b93360f33..a8cd5cf9ff5b 100644 --- a/include/net/inet_sock.h +++ b/include/net/inet_sock.h @@ -132,8 +132,7 @@ static inline int inet_request_bound_dev_if(const struct sock *sk, static inline struct ip_options_rcu *ireq_opt_deref(const struct inet_request_sock *ireq) { - return rcu_dereference_check(ireq->ireq_opt, - refcount_read(&ireq->req.rsk_refcnt) > 0); + return rcu_dereference(ireq->ireq_opt); } struct inet_cork { diff --git a/net/dccp/input.c b/net/dccp/input.c index d28d46bff6ab..85d6c879383d 100644 --- a/net/dccp/input.c +++ b/net/dccp/input.c @@ -606,11 +606,13 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, if (sk->sk_state == DCCP_LISTEN) { if (dh->dccph_type == DCCP_PKT_REQUEST) { /* It is possible that we process SYN packets from backlog, - * so we need to make sure to disable BH right there. + * so we need to make sure to disable BH and RCU right there. */ + rcu_read_lock(); local_bh_disable(); acceptable = inet_csk(sk)->icsk_af_ops->conn_request(sk, skb) >= 0; local_bh_enable(); + rcu_read_unlock(); if (!acceptable) return 1; consume_skb(skb); diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 4cf2f7bb2802..47e08c1b5bc3 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -6009,11 +6009,13 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb) if (th->fin) goto discard; /* It is possible that we process SYN packets from backlog, - * so we need to make sure to disable BH right there. + * so we need to make sure to disable BH and RCU right there. */ + rcu_read_lock(); local_bh_disable(); acceptable = icsk->icsk_af_ops->conn_request(sk, skb) >= 0; local_bh_enable(); + rcu_read_unlock(); if (!acceptable) return 1; -- cgit v1.2.3 From 2ab2ddd301a22ca3c5f0b743593e4ad2953dfa53 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 2 Oct 2018 12:35:05 -0700 Subject: inet: make sure to grab rcu_read_lock before using ireq->ireq_opt Timer handlers do not imply rcu_read_lock(), so my recent fix triggered a LOCKDEP warning when SYNACK is retransmit. Lets add rcu_read_lock()/rcu_read_unlock() pairs around ireq->ireq_opt usages instead of guessing what is done by callers, since it is not worth the pain. Get rid of ireq_opt_deref() helper since it hides the logic without real benefit, since it is now a standard rcu_dereference(). Fixes: 1ad98e9d1bdf ("tcp/dccp: fix lockdep issue when SYN is backlogged") Signed-off-by: Eric Dumazet Reported-by: Willem de Bruijn Signed-off-by: David S. Miller --- include/net/inet_sock.h | 5 ----- net/dccp/ipv4.c | 4 +++- net/ipv4/inet_connection_sock.c | 5 ++++- net/ipv4/tcp_ipv4.c | 4 +++- 4 files changed, 10 insertions(+), 8 deletions(-) (limited to 'net/ipv4') diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h index a8cd5cf9ff5b..a80fd0ac4563 100644 --- a/include/net/inet_sock.h +++ b/include/net/inet_sock.h @@ -130,11 +130,6 @@ static inline int inet_request_bound_dev_if(const struct sock *sk, return sk->sk_bound_dev_if; } -static inline struct ip_options_rcu *ireq_opt_deref(const struct inet_request_sock *ireq) -{ - return rcu_dereference(ireq->ireq_opt); -} - struct inet_cork { unsigned int flags; __be32 addr; diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c index b08feb219b44..8e08cea6f178 100644 --- a/net/dccp/ipv4.c +++ b/net/dccp/ipv4.c @@ -493,9 +493,11 @@ static int dccp_v4_send_response(const struct sock *sk, struct request_sock *req dh->dccph_checksum = dccp_v4_csum_finish(skb, ireq->ir_loc_addr, ireq->ir_rmt_addr); + rcu_read_lock(); err = ip_build_and_send_pkt(skb, sk, ireq->ir_loc_addr, ireq->ir_rmt_addr, - ireq_opt_deref(ireq)); + rcu_dereference(ireq->ireq_opt)); + rcu_read_unlock(); err = net_xmit_eval(err); } diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c index dfd5009f96ef..15e7f7915a21 100644 --- a/net/ipv4/inet_connection_sock.c +++ b/net/ipv4/inet_connection_sock.c @@ -544,7 +544,8 @@ struct dst_entry *inet_csk_route_req(const struct sock *sk, struct ip_options_rcu *opt; struct rtable *rt; - opt = ireq_opt_deref(ireq); + rcu_read_lock(); + opt = rcu_dereference(ireq->ireq_opt); flowi4_init_output(fl4, ireq->ir_iif, ireq->ir_mark, RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE, @@ -558,11 +559,13 @@ struct dst_entry *inet_csk_route_req(const struct sock *sk, goto no_route; if (opt && opt->opt.is_strictroute && rt->rt_uses_gateway) goto route_err; + rcu_read_unlock(); return &rt->dst; route_err: ip_rt_put(rt); no_route: + rcu_read_unlock(); __IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES); return NULL; } diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 44c09eddbb78..cd426313a298 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -943,9 +943,11 @@ static int tcp_v4_send_synack(const struct sock *sk, struct dst_entry *dst, if (skb) { __tcp_v4_send_check(skb, ireq->ir_loc_addr, ireq->ir_rmt_addr); + rcu_read_lock(); err = ip_build_and_send_pkt(skb, sk, ireq->ir_loc_addr, ireq->ir_rmt_addr, - ireq_opt_deref(ireq)); + rcu_dereference(ireq->ireq_opt)); + rcu_read_unlock(); err = net_xmit_eval(err); } -- cgit v1.2.3 From 64199fc0a46ba211362472f7f942f900af9492fd Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sun, 30 Sep 2018 11:33:39 -0700 Subject: ipv4: fix use-after-free in ip_cmsg_recv_dstaddr() Caching ip_hdr(skb) before a call to pskb_may_pull() is buggy, do not do it. Fixes: 2efd4fca703a ("ip: in cmsg IP(V6)_ORIGDSTADDR call pskb_may_pull") Signed-off-by: Eric Dumazet Cc: Willem de Bruijn Reported-by: syzbot Acked-by: Willem de Bruijn Signed-off-by: David S. Miller --- net/ipv4/ip_sockglue.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'net/ipv4') diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index c0fe5ad996f2..26c36cccabdc 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -149,7 +149,6 @@ static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb) static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb) { struct sockaddr_in sin; - const struct iphdr *iph = ip_hdr(skb); __be16 *ports; int end; @@ -164,7 +163,7 @@ static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb) ports = (__be16 *)skb_transport_header(skb); sin.sin_family = AF_INET; - sin.sin_addr.s_addr = iph->daddr; + sin.sin_addr.s_addr = ip_hdr(skb)->daddr; sin.sin_port = ports[1]; memset(sin.sin_zero, 0, sizeof(sin.sin_zero)); -- cgit v1.2.3