From 61ee4137b5744d9c555cd4674aae353a45f9cd2e Mon Sep 17 00:00:00 2001 From: YueHaibing Date: Fri, 31 Jul 2020 14:49:52 +0800 Subject: ip_vti: Fix unused variable warning If CONFIG_INET_XFRM_TUNNEL is set but CONFIG_IPV6 is n, net/ipv4/ip_vti.c:493:27: warning: 'vti_ipip6_handler' defined but not used [-Wunused-variable] Signed-off-by: YueHaibing Signed-off-by: Steffen Klassert --- net/ipv4/ip_vti.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'net/ipv4') diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c index 49daaed89764..f687abb069fa 100644 --- a/net/ipv4/ip_vti.c +++ b/net/ipv4/ip_vti.c @@ -490,6 +490,7 @@ static struct xfrm_tunnel vti_ipip_handler __read_mostly = { .priority = 0, }; +#if IS_ENABLED(CONFIG_IPV6) static struct xfrm_tunnel vti_ipip6_handler __read_mostly = { .handler = vti_rcv_tunnel, .cb_handler = vti_rcv_cb, @@ -497,6 +498,7 @@ static struct xfrm_tunnel vti_ipip6_handler __read_mostly = { .priority = 0, }; #endif +#endif static int __net_init vti_init_net(struct net *net) { -- cgit v1.2.3 From ad2b9b0f8d0107602bdc1f3b1ab90719842ace11 Mon Sep 17 00:00:00 2001 From: Priyaranjan Jha Date: Thu, 24 Sep 2020 15:23:14 -0700 Subject: tcp: skip DSACKs with dubious sequence ranges Currently, we use length of DSACKed range to compute number of delivered packets. And if sequence range in DSACK is corrupted, we can get bogus dsacked/acked count, and bogus cwnd. This patch put bounds on DSACKed range to skip update of data delivery and spurious retransmission information, if the DSACK is unlikely caused by sender's action: - DSACKed range shouldn't be greater than maximum advertised rwnd. - Total no. of DSACKed segments shouldn't be greater than total no. of retransmitted segs. Unlike spurious retransmits, network duplicates or corrupted DSACKs shouldn't be counted as delivery. Signed-off-by: Priyaranjan Jha Signed-off-by: Neal Cardwell Signed-off-by: Yuchung Cheng Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/uapi/linux/snmp.h | 1 + net/ipv4/proc.c | 1 + net/ipv4/tcp_input.c | 32 +++++++++++++++++++++++++------- 3 files changed, 27 insertions(+), 7 deletions(-) (limited to 'net/ipv4') diff --git a/include/uapi/linux/snmp.h b/include/uapi/linux/snmp.h index cee9f8e6fce3..f84e7bcad6de 100644 --- a/include/uapi/linux/snmp.h +++ b/include/uapi/linux/snmp.h @@ -288,6 +288,7 @@ enum LINUX_MIB_TCPTIMEOUTREHASH, /* TCPTimeoutRehash */ LINUX_MIB_TCPDUPLICATEDATAREHASH, /* TCPDuplicateDataRehash */ LINUX_MIB_TCPDSACKRECVSEGS, /* TCPDSACKRecvSegs */ + LINUX_MIB_TCPDSACKIGNOREDDUBIOUS, /* TCPDSACKIgnoredDubious */ __LINUX_MIB_MAX }; diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c index 1074df726ec0..8d5e1695b9aa 100644 --- a/net/ipv4/proc.c +++ b/net/ipv4/proc.c @@ -293,6 +293,7 @@ static const struct snmp_mib snmp4_net_list[] = { SNMP_MIB_ITEM("TcpTimeoutRehash", LINUX_MIB_TCPTIMEOUTREHASH), SNMP_MIB_ITEM("TcpDuplicateDataRehash", LINUX_MIB_TCPDUPLICATEDATAREHASH), SNMP_MIB_ITEM("TCPDSACKRecvSegs", LINUX_MIB_TCPDSACKRECVSEGS), + SNMP_MIB_ITEM("TCPDSACKIgnoredDubious", LINUX_MIB_TCPDSACKIGNOREDDUBIOUS), SNMP_MIB_SENTINEL }; diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 184ea556f50e..b1ce2054291d 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -885,21 +885,34 @@ struct tcp_sacktag_state { struct rate_sample *rate; }; -/* Take a notice that peer is sending D-SACKs */ +/* Take a notice that peer is sending D-SACKs. Skip update of data delivery + * and spurious retransmission information if this DSACK is unlikely caused by + * sender's action: + * - DSACKed sequence range is larger than maximum receiver's window. + * - Total no. of DSACKed segments exceed the total no. of retransmitted segs. + */ static u32 tcp_dsack_seen(struct tcp_sock *tp, u32 start_seq, u32 end_seq, struct tcp_sacktag_state *state) { u32 seq_len, dup_segs = 1; - if (before(start_seq, end_seq)) { - seq_len = end_seq - start_seq; - if (seq_len > tp->mss_cache) - dup_segs = DIV_ROUND_UP(seq_len, tp->mss_cache); - } + if (!before(start_seq, end_seq)) + return 0; + + seq_len = end_seq - start_seq; + /* Dubious DSACK: DSACKed range greater than maximum advertised rwnd */ + if (seq_len > tp->max_window) + return 0; + if (seq_len > tp->mss_cache) + dup_segs = DIV_ROUND_UP(seq_len, tp->mss_cache); + + tp->dsack_dups += dup_segs; + /* Skip the DSACK if dup segs weren't retransmitted by sender */ + if (tp->dsack_dups > tp->total_retrans) + return 0; tp->rx_opt.sack_ok |= TCP_DSACK_SEEN; tp->rack.dsack_seen = 1; - tp->dsack_dups += dup_segs; state->flag |= FLAG_DSACKING_ACK; /* A spurious retransmission is delivered */ @@ -1153,6 +1166,11 @@ static bool tcp_check_dsack(struct sock *sk, const struct sk_buff *ack_skb, } dup_segs = tcp_dsack_seen(tp, start_seq_0, end_seq_0, state); + if (!dup_segs) { /* Skip dubious DSACK */ + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPDSACKIGNOREDDUBIOUS); + return false; + } + NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPDSACKRECVSEGS, dup_segs); /* D-SACK for already forgotten data... Do dumb counting. */ -- cgit v1.2.3 From cf83a17edeeb36195596d2dae060a7c381db35f1 Mon Sep 17 00:00:00 2001 From: Coly Li Date: Fri, 2 Oct 2020 16:27:31 +0800 Subject: tcp: use sendpage_ok() to detect misused .sendpage commit a10674bf2406 ("tcp: detecting the misuse of .sendpage for Slab objects") adds the checks for Slab pages, but the pages don't have page_count are still missing from the check. Network layer's sendpage method is not designed to send page_count 0 pages neither, therefore both PageSlab() and page_count() should be both checked for the sending page. This is exactly what sendpage_ok() does. This patch uses sendpage_ok() in do_tcp_sendpages() to detect misused .sendpage, to make the code more robust. Fixes: a10674bf2406 ("tcp: detecting the misuse of .sendpage for Slab objects") Suggested-by: Eric Dumazet Signed-off-by: Coly Li Cc: Vasily Averin Cc: David S. Miller Cc: stable@vger.kernel.org Signed-off-by: David S. Miller --- net/ipv4/tcp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/ipv4') diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 31f3b858db81..2135ee7c806d 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -970,7 +970,8 @@ ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset, long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); if (IS_ENABLED(CONFIG_DEBUG_VM) && - WARN_ONCE(PageSlab(page), "page must not be a Slab one")) + WARN_ONCE(!sendpage_ok(page), + "page must not be a Slab one and have page_count > 0")) return -EINVAL; /* Wait for a connection to finish. One exception is TCP Fast Open -- cgit v1.2.3 From 9d8c05ad5627b3a650087c14c67dd1d22a6368ab Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Fri, 2 Oct 2020 12:39:44 +0200 Subject: tcp: fix syn cookied MPTCP request socket leak If a syn-cookies request socket don't pass MPTCP-level validation done in syn_recv_sock(), we need to release it immediately, or it will be leaked. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/89 Fixes: 9466a1ccebbe ("mptcp: enable JOIN requests even if cookies are in use") Reported-and-tested-by: Geliang Tang Reviewed-by: Matthieu Baerts Signed-off-by: Paolo Abeni Signed-off-by: David S. Miller --- net/ipv4/syncookies.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/ipv4') diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c index f0794f0232ba..e03756631541 100644 --- a/net/ipv4/syncookies.c +++ b/net/ipv4/syncookies.c @@ -214,7 +214,7 @@ struct sock *tcp_get_cookie_sock(struct sock *sk, struct sk_buff *skb, sock_rps_save_rxhash(child, skb); if (rsk_drop_req(req)) { - refcount_set(&req->rsk_refcnt, 2); + reqsk_put(req); return child; } -- cgit v1.2.3