From a399a8053164ec8bcb06fed52be9941a26ecde11 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 8 Aug 2012 21:13:53 +0000 Subject: time: jiffies_delta_to_clock_t() helper to the rescue MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Various /proc/net files sometimes report crazy timer values, expressed in clock_t units. This happens when an expired timer delta (expires - jiffies) is passed to jiffies_to_clock_t(). This function has an overflow in : return div_u64((u64)x * TICK_NSEC, NSEC_PER_SEC / USER_HZ); commit cbbc719fccdb8cb (time: Change jiffies_to_clock_t() argument type to unsigned long) only got around the problem. As we cant output negative values in /proc/net/tcp without breaking various tools, I suggest adding a jiffies_delta_to_clock_t() wrapper that caps the negative delta to a 0 value. Signed-off-by: Eric Dumazet Reported-by: Maciej Żenczykowski Cc: Thomas Gleixner Cc: Paul Gortmaker Cc: Andrew Morton Cc: hank Signed-off-by: David S. Miller --- net/ipv4/tcp_ipv4.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) (limited to 'net/ipv4/tcp_ipv4.c') diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 42b2a6a7309..c660d2c19a2 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2385,7 +2385,7 @@ static void get_openreq4(const struct sock *sk, const struct request_sock *req, struct seq_file *f, int i, int uid, int *len) { const struct inet_request_sock *ireq = inet_rsk(req); - int ttd = req->expires - jiffies; + long delta = req->expires - jiffies; seq_printf(f, "%4d: %08X:%04X %08X:%04X" " %02X %08X:%08X %02X:%08lX %08X %5d %8d %u %d %pK%n", @@ -2397,7 +2397,7 @@ static void get_openreq4(const struct sock *sk, const struct request_sock *req, TCP_SYN_RECV, 0, 0, /* could print option size, but that is af dependent. */ 1, /* timers active (only the expire timer) */ - jiffies_to_clock_t(ttd), + jiffies_delta_to_clock_t(delta), req->retrans, uid, 0, /* non standard timer */ @@ -2448,7 +2448,7 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i, int *len) tp->write_seq - tp->snd_una, rx_queue, timer_active, - jiffies_to_clock_t(timer_expires - jiffies), + jiffies_delta_to_clock_t(timer_expires - jiffies), icsk->icsk_retransmits, sock_i_uid(sk), icsk->icsk_probes_out, @@ -2467,10 +2467,7 @@ static void get_timewait4_sock(const struct inet_timewait_sock *tw, { __be32 dest, src; __u16 destp, srcp; - int ttd = tw->tw_ttd - jiffies; - - if (ttd < 0) - ttd = 0; + long delta = tw->tw_ttd - jiffies; dest = tw->tw_daddr; src = tw->tw_rcv_saddr; @@ -2480,7 +2477,7 @@ static void get_timewait4_sock(const struct inet_timewait_sock *tw, seq_printf(f, "%4d: %08X:%04X %08X:%04X" " %02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK%n", i, src, srcp, dest, destp, tw->tw_substate, 0, 0, - 3, jiffies_to_clock_t(ttd), 0, 0, 0, 0, + 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, atomic_read(&tw->tw_refcnt), tw, len); } -- cgit v1.2.3-70-g09d2 From a7cb5a49bf64ba64864ae16a6be028f8b0d3cc06 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Thu, 24 May 2012 01:10:10 -0600 Subject: userns: Print out socket uids in a user namespace aware fashion. Cc: Alexey Kuznetsov Cc: James Morris Cc: Hideaki YOSHIFUJI Cc: Patrick McHardy Cc: Arnaldo Carvalho de Melo Cc: Sridhar Samudrala Acked-by: Vlad Yasevich Acked-by: David S. Miller Acked-by: Serge Hallyn Signed-off-by: Eric W. Biederman --- include/net/tcp.h | 3 ++- init/Kconfig | 6 ------ net/appletalk/atalk_proc.c | 3 ++- net/ipv4/ping.c | 4 +++- net/ipv4/raw.c | 4 +++- net/ipv4/tcp_ipv4.c | 6 +++--- net/ipv4/udp.c | 4 +++- net/ipv6/raw.c | 3 ++- net/ipv6/tcp_ipv6.c | 6 +++--- net/ipv6/udp.c | 3 ++- net/ipx/ipx_proc.c | 3 ++- net/key/af_key.c | 2 +- net/llc/llc_proc.c | 2 +- net/packet/af_packet.c | 2 +- net/phonet/socket.c | 6 ++++-- net/sctp/proc.c | 6 ++++-- 16 files changed, 36 insertions(+), 27 deletions(-) (limited to 'net/ipv4/tcp_ipv4.c') diff --git a/include/net/tcp.h b/include/net/tcp.h index e19124b84cd..91e746736a8 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1509,7 +1509,8 @@ struct tcp_iter_state { sa_family_t family; enum tcp_seq_states state; struct sock *syn_wait_sk; - int bucket, offset, sbucket, num, uid; + int bucket, offset, sbucket, num; + kuid_t uid; loff_t last_pos; }; diff --git a/init/Kconfig b/init/Kconfig index 80fae193e3a..25a6ebb50c6 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -942,10 +942,7 @@ config UIDGID_CONVERTED depends on PROC_EVENTS = n # Networking - depends on PACKET = n depends on NET_9P = n - depends on IPX = n - depends on PHONET = n depends on NET_CLS_FLOW = n depends on NETFILTER_XT_MATCH_OWNER = n depends on NETFILTER_XT_MATCH_RECENT = n @@ -953,14 +950,11 @@ config UIDGID_CONVERTED depends on NETFILTER_NETLINK_LOG = n depends on INET = n depends on IPV6 = n - depends on IP_SCTP = n depends on AF_RXRPC = n - depends on LLC2 = n depends on NET_KEY = n depends on INET_DIAG = n depends on DNS_RESOLVER = n depends on AX25 = n - depends on ATALK = n # Filesystems depends on USB_GADGETFS = n diff --git a/net/appletalk/atalk_proc.c b/net/appletalk/atalk_proc.c index b5b1a221c24..c30f3a0717f 100644 --- a/net/appletalk/atalk_proc.c +++ b/net/appletalk/atalk_proc.c @@ -183,7 +183,8 @@ static int atalk_seq_socket_show(struct seq_file *seq, void *v) ntohs(at->dest_net), at->dest_node, at->dest_port, sk_wmem_alloc_get(s), sk_rmem_alloc_get(s), - s->sk_state, SOCK_INODE(s->sk_socket)->i_uid); + s->sk_state, + from_kuid_munged(seq_user_ns(seq), sock_i_uid(s))); out: return 0; } diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c index 6232d476f37..bee5eeb676f 100644 --- a/net/ipv4/ping.c +++ b/net/ipv4/ping.c @@ -845,7 +845,9 @@ static void ping_format_sock(struct sock *sp, struct seq_file *f, bucket, src, srcp, dest, destp, sp->sk_state, sk_wmem_alloc_get(sp), sk_rmem_alloc_get(sp), - 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp), + 0, 0L, 0, + from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)), + 0, sock_i_ino(sp), atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops), len); } diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index ff0f071969e..f2425785d40 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -992,7 +992,9 @@ static void raw_sock_seq_show(struct seq_file *seq, struct sock *sp, int i) i, src, srcp, dest, destp, sp->sk_state, sk_wmem_alloc_get(sp), sk_rmem_alloc_get(sp), - 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp), + 0, 0L, 0, + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), + 0, sock_i_ino(sp), atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops)); } diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 42b2a6a7309..642be8a4c6a 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2382,7 +2382,7 @@ void tcp_proc_unregister(struct net *net, struct tcp_seq_afinfo *afinfo) EXPORT_SYMBOL(tcp_proc_unregister); static void get_openreq4(const struct sock *sk, const struct request_sock *req, - struct seq_file *f, int i, int uid, int *len) + struct seq_file *f, int i, kuid_t uid, int *len) { const struct inet_request_sock *ireq = inet_rsk(req); int ttd = req->expires - jiffies; @@ -2399,7 +2399,7 @@ static void get_openreq4(const struct sock *sk, const struct request_sock *req, 1, /* timers active (only the expire timer) */ jiffies_to_clock_t(ttd), req->retrans, - uid, + from_kuid_munged(seq_user_ns(f), uid), 0, /* non standard timer */ 0, /* open_requests have no inode */ atomic_read(&sk->sk_refcnt), @@ -2450,7 +2450,7 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i, int *len) timer_active, jiffies_to_clock_t(timer_expires - jiffies), icsk->icsk_retransmits, - sock_i_uid(sk), + from_kuid_munged(seq_user_ns(f), sock_i_uid(sk)), icsk->icsk_probes_out, sock_i_ino(sk), atomic_read(&sk->sk_refcnt), sk, diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index b4c3582a991..53b89817c00 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -2110,7 +2110,9 @@ static void udp4_format_sock(struct sock *sp, struct seq_file *f, bucket, src, srcp, dest, destp, sp->sk_state, sk_wmem_alloc_get(sp), sk_rmem_alloc_get(sp), - 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp), + 0, 0L, 0, + from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)), + 0, sock_i_ino(sp), atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops), len); } diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index ef0579d5bca..7af88ef0165 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -1251,7 +1251,8 @@ static void raw6_sock_seq_show(struct seq_file *seq, struct sock *sp, int i) sk_wmem_alloc_get(sp), sk_rmem_alloc_get(sp), 0, 0L, 0, - sock_i_uid(sp), 0, + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), + 0, sock_i_ino(sp), atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops)); } diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index c66b90f71c9..4b5b335ebde 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1803,7 +1803,7 @@ static void tcp_v6_destroy_sock(struct sock *sk) #ifdef CONFIG_PROC_FS /* Proc filesystem TCPv6 sock list dumping. */ static void get_openreq6(struct seq_file *seq, - const struct sock *sk, struct request_sock *req, int i, int uid) + const struct sock *sk, struct request_sock *req, int i, kuid_t uid) { int ttd = req->expires - jiffies; const struct in6_addr *src = &inet6_rsk(req)->loc_addr; @@ -1827,7 +1827,7 @@ static void get_openreq6(struct seq_file *seq, 1, /* timers active (only the expire timer) */ jiffies_to_clock_t(ttd), req->retrans, - uid, + from_kuid_munged(seq_user_ns(seq), uid), 0, /* non standard timer */ 0, /* open_requests have no inode */ 0, req); @@ -1877,7 +1877,7 @@ static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) timer_active, jiffies_to_clock_t(timer_expires - jiffies), icsk->icsk_retransmits, - sock_i_uid(sp), + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), icsk->icsk_probes_out, sock_i_ino(sp), atomic_read(&sp->sk_refcnt), sp, diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 99d0077b56b..bbdff07eebe 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -1458,7 +1458,8 @@ static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket sk_wmem_alloc_get(sp), sk_rmem_alloc_get(sp), 0, 0L, 0, - sock_i_uid(sp), 0, + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), + 0, sock_i_ino(sp), atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops)); diff --git a/net/ipx/ipx_proc.c b/net/ipx/ipx_proc.c index f8ba30dfeca..02ff7f2f60d 100644 --- a/net/ipx/ipx_proc.c +++ b/net/ipx/ipx_proc.c @@ -217,7 +217,8 @@ static int ipx_seq_socket_show(struct seq_file *seq, void *v) seq_printf(seq, "%08X %08X %02X %03d\n", sk_wmem_alloc_get(s), sk_rmem_alloc_get(s), - s->sk_state, SOCK_INODE(s->sk_socket)->i_uid); + s->sk_state, + from_kuid_munged(seq_user_ns(seq), sock_i_uid(s))); out: return 0; } diff --git a/net/key/af_key.c b/net/key/af_key.c index 34e418508a6..0481d4b5147 100644 --- a/net/key/af_key.c +++ b/net/key/af_key.c @@ -3661,7 +3661,7 @@ static int pfkey_seq_show(struct seq_file *f, void *v) atomic_read(&s->sk_refcnt), sk_rmem_alloc_get(s), sk_wmem_alloc_get(s), - sock_i_uid(s), + from_kuid_munged(seq_user_ns(f), sock_i_uid(s)), sock_i_ino(s) ); return 0; diff --git a/net/llc/llc_proc.c b/net/llc/llc_proc.c index a1839c00435..7b4799cfbf8 100644 --- a/net/llc/llc_proc.c +++ b/net/llc/llc_proc.c @@ -151,7 +151,7 @@ static int llc_seq_socket_show(struct seq_file *seq, void *v) sk_wmem_alloc_get(sk), sk_rmem_alloc_get(sk) - llc->copied_seq, sk->sk_state, - sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : -1, + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), llc->link); out: return 0; diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index ceaca7c134a..d147317ce9e 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -3846,7 +3846,7 @@ static int packet_seq_show(struct seq_file *seq, void *v) po->ifindex, po->running, atomic_read(&s->sk_rmem_alloc), - sock_i_uid(s), + from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)), sock_i_ino(s)); } diff --git a/net/phonet/socket.c b/net/phonet/socket.c index 0acc943f713..b7e98278225 100644 --- a/net/phonet/socket.c +++ b/net/phonet/socket.c @@ -612,7 +612,8 @@ static int pn_sock_seq_show(struct seq_file *seq, void *v) sk->sk_protocol, pn->sobject, pn->dobject, pn->resource, sk->sk_state, sk_wmem_alloc_get(sk), sk_rmem_alloc_get(sk), - sock_i_uid(sk), sock_i_ino(sk), + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), + sock_i_ino(sk), atomic_read(&sk->sk_refcnt), sk, atomic_read(&sk->sk_drops), &len); } @@ -796,7 +797,8 @@ static int pn_res_seq_show(struct seq_file *seq, void *v) struct sock *sk = *psk; seq_printf(seq, "%02X %5d %lu%n", - (int) (psk - pnres.sk), sock_i_uid(sk), + (int) (psk - pnres.sk), + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), sock_i_ino(sk), &len); } seq_printf(seq, "%*s\n", 63 - len, ""); diff --git a/net/sctp/proc.c b/net/sctp/proc.c index 1e2eee88c3e..dc12febc977 100644 --- a/net/sctp/proc.c +++ b/net/sctp/proc.c @@ -216,7 +216,8 @@ static int sctp_eps_seq_show(struct seq_file *seq, void *v) seq_printf(seq, "%8pK %8pK %-3d %-3d %-4d %-5d %5d %5lu ", ep, sk, sctp_sk(sk)->type, sk->sk_state, hash, epb->bind_addr.port, - sock_i_uid(sk), sock_i_ino(sk)); + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), + sock_i_ino(sk)); sctp_seq_dump_local_addrs(seq, epb); seq_printf(seq, "\n"); @@ -324,7 +325,8 @@ static int sctp_assocs_seq_show(struct seq_file *seq, void *v) assoc->assoc_id, assoc->sndbuf_used, atomic_read(&assoc->rmem_alloc), - sock_i_uid(sk), sock_i_ino(sk), + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), + sock_i_ino(sk), epb->bind_addr.port, assoc->peer.port); seq_printf(seq, " "); -- cgit v1.2.3-70-g09d2 From 8336886f786fdacbc19b719c1f7ea91eb70706d4 Mon Sep 17 00:00:00 2001 From: Jerry Chu Date: Fri, 31 Aug 2012 12:29:12 +0000 Subject: tcp: TCP Fast Open Server - support TFO listeners This patch builds on top of the previous patch to add the support for TFO listeners. This includes - 1. allocating, properly initializing, and managing the per listener fastopen_queue structure when TFO is enabled 2. changes to the inet_csk_accept code to support TFO. E.g., the request_sock can no longer be freed upon accept(), not until 3WHS finishes 3. allowing a TCP_SYN_RECV socket to properly poll() and sendmsg() if it's a TFO socket 4. properly closing a TFO listener, and a TFO socket before 3WHS finishes 5. supporting TCP_FASTOPEN socket option 6. modifying tcp_check_req() to use to check a TFO socket as well as request_sock 7. supporting TCP's TFO cookie option 8. adding a new SYN-ACK retransmit handler to use the timer directly off the TFO socket rather than the listener socket. Note that TFO server side will not retransmit anything other than SYN-ACK until the 3WHS is completed. The patch also contains an important function "reqsk_fastopen_remove()" to manage the somewhat complex relation between a listener, its request_sock, and the corresponding child socket. See the comment above the function for the detail. Signed-off-by: H.K. Jerry Chu Cc: Yuchung Cheng Cc: Neal Cardwell Cc: Eric Dumazet Cc: Tom Herbert Signed-off-by: David S. Miller --- include/net/request_sock.h | 13 ------ include/net/tcp.h | 6 ++- net/core/request_sock.c | 95 +++++++++++++++++++++++++++++++++++++++++ net/ipv4/af_inet.c | 28 +++++++++++- net/ipv4/inet_connection_sock.c | 57 ++++++++++++++++++++++--- net/ipv4/syncookies.c | 1 + net/ipv4/tcp.c | 49 ++++++++++++++++++--- net/ipv4/tcp_ipv4.c | 4 +- net/ipv4/tcp_minisocks.c | 61 +++++++++++++++++++++----- net/ipv4/tcp_output.c | 21 ++++++--- net/ipv4/tcp_timer.c | 39 ++++++++++++++++- net/ipv6/syncookies.c | 1 + net/ipv6/tcp_ipv6.c | 5 ++- 13 files changed, 330 insertions(+), 50 deletions(-) (limited to 'net/ipv4/tcp_ipv4.c') diff --git a/include/net/request_sock.h b/include/net/request_sock.h index c3cdd6c9f44..b01d8dd9ee7 100644 --- a/include/net/request_sock.h +++ b/include/net/request_sock.h @@ -226,19 +226,6 @@ static inline struct request_sock *reqsk_queue_remove(struct request_sock_queue return req; } -static inline struct sock *reqsk_queue_get_child(struct request_sock_queue *queue, - struct sock *parent) -{ - struct request_sock *req = reqsk_queue_remove(queue); - struct sock *child = req->sk; - - WARN_ON(child == NULL); - - sk_acceptq_removed(parent); - __reqsk_free(req); - return child; -} - static inline int reqsk_queue_removed(struct request_sock_queue *queue, struct request_sock *req) { diff --git a/include/net/tcp.h b/include/net/tcp.h index 9f8821e3293..1421b02a790 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -424,7 +424,8 @@ extern enum tcp_tw_status tcp_timewait_state_process(struct inet_timewait_sock * const struct tcphdr *th); extern struct sock * tcp_check_req(struct sock *sk,struct sk_buff *skb, struct request_sock *req, - struct request_sock **prev); + struct request_sock **prev, + bool fastopen); extern int tcp_child_process(struct sock *parent, struct sock *child, struct sk_buff *skb); extern bool tcp_use_frto(struct sock *sk); @@ -478,7 +479,8 @@ extern int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, extern int tcp_connect(struct sock *sk); extern struct sk_buff * tcp_make_synack(struct sock *sk, struct dst_entry *dst, struct request_sock *req, - struct request_values *rvp); + struct request_values *rvp, + struct tcp_fastopen_cookie *foc); extern int tcp_disconnect(struct sock *sk, int flags); void tcp_connect_init(struct sock *sk); diff --git a/net/core/request_sock.c b/net/core/request_sock.c index 9b570a6a33c..c31d9e8668c 100644 --- a/net/core/request_sock.c +++ b/net/core/request_sock.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include @@ -130,3 +131,97 @@ void reqsk_queue_destroy(struct request_sock_queue *queue) kfree(lopt); } +/* + * This function is called to set a Fast Open socket's "fastopen_rsk" field + * to NULL when a TFO socket no longer needs to access the request_sock. + * This happens only after 3WHS has been either completed or aborted (e.g., + * RST is received). + * + * Before TFO, a child socket is created only after 3WHS is completed, + * hence it never needs to access the request_sock. things get a lot more + * complex with TFO. A child socket, accepted or not, has to access its + * request_sock for 3WHS processing, e.g., to retransmit SYN-ACK pkts, + * until 3WHS is either completed or aborted. Afterwards the req will stay + * until either the child socket is accepted, or in the rare case when the + * listener is closed before the child is accepted. + * + * In short, a request socket is only freed after BOTH 3WHS has completed + * (or aborted) and the child socket has been accepted (or listener closed). + * When a child socket is accepted, its corresponding req->sk is set to + * NULL since it's no longer needed. More importantly, "req->sk == NULL" + * will be used by the code below to determine if a child socket has been + * accepted or not, and the check is protected by the fastopenq->lock + * described below. + * + * Note that fastopen_rsk is only accessed from the child socket's context + * with its socket lock held. But a request_sock (req) can be accessed by + * both its child socket through fastopen_rsk, and a listener socket through + * icsk_accept_queue.rskq_accept_head. To protect the access a simple spin + * lock per listener "icsk->icsk_accept_queue.fastopenq->lock" is created. + * only in the rare case when both the listener and the child locks are held, + * e.g., in inet_csk_listen_stop() do we not need to acquire the lock. + * The lock also protects other fields such as fastopenq->qlen, which is + * decremented by this function when fastopen_rsk is no longer needed. + * + * Note that another solution was to simply use the existing socket lock + * from the listener. But first socket lock is difficult to use. It is not + * a simple spin lock - one must consider sock_owned_by_user() and arrange + * to use sk_add_backlog() stuff. But what really makes it infeasible is the + * locking hierarchy violation. E.g., inet_csk_listen_stop() may try to + * acquire a child's lock while holding listener's socket lock. A corner + * case might also exist in tcp_v4_hnd_req() that will trigger this locking + * order. + * + * When a TFO req is created, it needs to sock_hold its listener to prevent + * the latter data structure from going away. + * + * This function also sets "treq->listener" to NULL and unreference listener + * socket. treq->listener is used by the listener so it is protected by the + * fastopenq->lock in this function. + */ +void reqsk_fastopen_remove(struct sock *sk, struct request_sock *req, + bool reset) +{ + struct sock *lsk = tcp_rsk(req)->listener; + struct fastopen_queue *fastopenq = + inet_csk(lsk)->icsk_accept_queue.fastopenq; + + BUG_ON(!spin_is_locked(&sk->sk_lock.slock) && !sock_owned_by_user(sk)); + + tcp_sk(sk)->fastopen_rsk = NULL; + spin_lock_bh(&fastopenq->lock); + fastopenq->qlen--; + tcp_rsk(req)->listener = NULL; + if (req->sk) /* the child socket hasn't been accepted yet */ + goto out; + + if (!reset || lsk->sk_state != TCP_LISTEN) { + /* If the listener has been closed don't bother with the + * special RST handling below. + */ + spin_unlock_bh(&fastopenq->lock); + sock_put(lsk); + reqsk_free(req); + return; + } + /* Wait for 60secs before removing a req that has triggered RST. + * This is a simple defense against TFO spoofing attack - by + * counting the req against fastopen.max_qlen, and disabling + * TFO when the qlen exceeds max_qlen. + * + * For more details see CoNext'11 "TCP Fast Open" paper. + */ + req->expires = jiffies + 60*HZ; + if (fastopenq->rskq_rst_head == NULL) + fastopenq->rskq_rst_head = req; + else + fastopenq->rskq_rst_tail->dl_next = req; + + req->dl_next = NULL; + fastopenq->rskq_rst_tail = req; + fastopenq->qlen++; +out: + spin_unlock_bh(&fastopenq->lock); + sock_put(lsk); + return; +} diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 6681ccf5c3e..4f70ef0b946 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -149,6 +149,11 @@ void inet_sock_destruct(struct sock *sk) pr_err("Attempt to release alive inet socket %p\n", sk); return; } + if (sk->sk_type == SOCK_STREAM) { + struct fastopen_queue *fastopenq = + inet_csk(sk)->icsk_accept_queue.fastopenq; + kfree(fastopenq); + } WARN_ON(atomic_read(&sk->sk_rmem_alloc)); WARN_ON(atomic_read(&sk->sk_wmem_alloc)); @@ -212,6 +217,26 @@ int inet_listen(struct socket *sock, int backlog) * we can only allow the backlog to be adjusted. */ if (old_state != TCP_LISTEN) { + /* Check special setups for testing purpose to enable TFO w/o + * requiring TCP_FASTOPEN sockopt. + * Note that only TCP sockets (SOCK_STREAM) will reach here. + * Also fastopenq may already been allocated because this + * socket was in TCP_LISTEN state previously but was + * shutdown() (rather than close()). + */ + if ((sysctl_tcp_fastopen & TFO_SERVER_ENABLE) != 0 && + inet_csk(sk)->icsk_accept_queue.fastopenq == NULL) { + if ((sysctl_tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) != 0) + err = fastopen_init_queue(sk, backlog); + else if ((sysctl_tcp_fastopen & + TFO_SERVER_WO_SOCKOPT2) != 0) + err = fastopen_init_queue(sk, + ((uint)sysctl_tcp_fastopen) >> 16); + else + err = 0; + if (err) + goto out; + } err = inet_csk_listen_start(sk, backlog); if (err) goto out; @@ -701,7 +726,8 @@ int inet_accept(struct socket *sock, struct socket *newsock, int flags) sock_rps_record_flow(sk2); WARN_ON(!((1 << sk2->sk_state) & - (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE))); + (TCPF_ESTABLISHED | TCPF_SYN_RECV | + TCPF_CLOSE_WAIT | TCPF_CLOSE))); sock_graft(sk2, newsock); diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c index 7f75f21d7b8..8464b79c493 100644 --- a/net/ipv4/inet_connection_sock.c +++ b/net/ipv4/inet_connection_sock.c @@ -283,7 +283,9 @@ static int inet_csk_wait_for_connect(struct sock *sk, long timeo) struct sock *inet_csk_accept(struct sock *sk, int flags, int *err) { struct inet_connection_sock *icsk = inet_csk(sk); + struct request_sock_queue *queue = &icsk->icsk_accept_queue; struct sock *newsk; + struct request_sock *req; int error; lock_sock(sk); @@ -296,7 +298,7 @@ struct sock *inet_csk_accept(struct sock *sk, int flags, int *err) goto out_err; /* Find already established connection */ - if (reqsk_queue_empty(&icsk->icsk_accept_queue)) { + if (reqsk_queue_empty(queue)) { long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK); /* If this is a non blocking socket don't sleep */ @@ -308,14 +310,32 @@ struct sock *inet_csk_accept(struct sock *sk, int flags, int *err) if (error) goto out_err; } - - newsk = reqsk_queue_get_child(&icsk->icsk_accept_queue, sk); - WARN_ON(newsk->sk_state == TCP_SYN_RECV); + req = reqsk_queue_remove(queue); + newsk = req->sk; + + sk_acceptq_removed(sk); + if (sk->sk_type == SOCK_STREAM && queue->fastopenq != NULL) { + spin_lock_bh(&queue->fastopenq->lock); + if (tcp_rsk(req)->listener) { + /* We are still waiting for the final ACK from 3WHS + * so can't free req now. Instead, we set req->sk to + * NULL to signify that the child socket is taken + * so reqsk_fastopen_remove() will free the req + * when 3WHS finishes (or is aborted). + */ + req->sk = NULL; + req = NULL; + } + spin_unlock_bh(&queue->fastopenq->lock); + } out: release_sock(sk); + if (req) + __reqsk_free(req); return newsk; out_err: newsk = NULL; + req = NULL; *err = error; goto out; } @@ -720,13 +740,14 @@ EXPORT_SYMBOL_GPL(inet_csk_listen_start); void inet_csk_listen_stop(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); + struct request_sock_queue *queue = &icsk->icsk_accept_queue; struct request_sock *acc_req; struct request_sock *req; inet_csk_delete_keepalive_timer(sk); /* make all the listen_opt local to us */ - acc_req = reqsk_queue_yank_acceptq(&icsk->icsk_accept_queue); + acc_req = reqsk_queue_yank_acceptq(queue); /* Following specs, it would be better either to send FIN * (and enter FIN-WAIT-1, it is normal close) @@ -736,7 +757,7 @@ void inet_csk_listen_stop(struct sock *sk) * To be honest, we are not able to make either * of the variants now. --ANK */ - reqsk_queue_destroy(&icsk->icsk_accept_queue); + reqsk_queue_destroy(queue); while ((req = acc_req) != NULL) { struct sock *child = req->sk; @@ -754,6 +775,19 @@ void inet_csk_listen_stop(struct sock *sk) percpu_counter_inc(sk->sk_prot->orphan_count); + if (sk->sk_type == SOCK_STREAM && tcp_rsk(req)->listener) { + BUG_ON(tcp_sk(child)->fastopen_rsk != req); + BUG_ON(sk != tcp_rsk(req)->listener); + + /* Paranoid, to prevent race condition if + * an inbound pkt destined for child is + * blocked by sock lock in tcp_v4_rcv(). + * Also to satisfy an assertion in + * tcp_v4_destroy_sock(). + */ + tcp_sk(child)->fastopen_rsk = NULL; + sock_put(sk); + } inet_csk_destroy_sock(child); bh_unlock_sock(child); @@ -763,6 +797,17 @@ void inet_csk_listen_stop(struct sock *sk) sk_acceptq_removed(sk); __reqsk_free(req); } + if (queue->fastopenq != NULL) { + /* Free all the reqs queued in rskq_rst_head. */ + spin_lock_bh(&queue->fastopenq->lock); + acc_req = queue->fastopenq->rskq_rst_head; + queue->fastopenq->rskq_rst_head = NULL; + spin_unlock_bh(&queue->fastopenq->lock); + while ((req = acc_req) != NULL) { + acc_req = req->dl_next; + __reqsk_free(req); + } + } WARN_ON(sk->sk_ack_backlog); } EXPORT_SYMBOL_GPL(inet_csk_listen_stop); diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c index 650e1528e1e..ba48e799b03 100644 --- a/net/ipv4/syncookies.c +++ b/net/ipv4/syncookies.c @@ -319,6 +319,7 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb, ireq->tstamp_ok = tcp_opt.saw_tstamp; req->ts_recent = tcp_opt.saw_tstamp ? tcp_opt.rcv_tsval : 0; treq->snt_synack = tcp_opt.saw_tstamp ? tcp_opt.rcv_tsecr : 0; + treq->listener = NULL; /* We throwed the options of the initial SYN away, so we hope * the ACK carries the same options again (see RFC1122 4.2.3.8) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 2109ff4a1da..df83d744e38 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -486,8 +486,9 @@ unsigned int tcp_poll(struct file *file, struct socket *sock, poll_table *wait) if (sk->sk_shutdown & RCV_SHUTDOWN) mask |= POLLIN | POLLRDNORM | POLLRDHUP; - /* Connected? */ - if ((1 << sk->sk_state) & ~(TCPF_SYN_SENT | TCPF_SYN_RECV)) { + /* Connected or passive Fast Open socket? */ + if (sk->sk_state != TCP_SYN_SENT && + (sk->sk_state != TCP_SYN_RECV || tp->fastopen_rsk != NULL)) { int target = sock_rcvlowat(sk, 0, INT_MAX); if (tp->urg_seq == tp->copied_seq && @@ -840,10 +841,15 @@ static ssize_t do_tcp_sendpages(struct sock *sk, struct page **pages, int poffse ssize_t copied; long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); - /* Wait for a connection to finish. */ - if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) + /* Wait for a connection to finish. One exception is TCP Fast Open + * (passive side) where data is allowed to be sent before a connection + * is fully established. + */ + if (((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) && + !tcp_passive_fastopen(sk)) { if ((err = sk_stream_wait_connect(sk, &timeo)) != 0) goto out_err; + } clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); @@ -1042,10 +1048,15 @@ int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); - /* Wait for a connection to finish. */ - if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) + /* Wait for a connection to finish. One exception is TCP Fast Open + * (passive side) where data is allowed to be sent before a connection + * is fully established. + */ + if (((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) && + !tcp_passive_fastopen(sk)) { if ((err = sk_stream_wait_connect(sk, &timeo)) != 0) goto do_error; + } if (unlikely(tp->repair)) { if (tp->repair_queue == TCP_RECV_QUEUE) { @@ -2144,6 +2155,10 @@ void tcp_close(struct sock *sk, long timeout) * they look as CLOSING or LAST_ACK for Linux) * Probably, I missed some more holelets. * --ANK + * XXX (TFO) - To start off we don't support SYN+ACK+FIN + * in a single packet! (May consider it later but will + * probably need API support or TCP_CORK SYN-ACK until + * data is written and socket is closed.) */ tcp_send_fin(sk); } @@ -2215,8 +2230,16 @@ adjudge_to_death: } } - if (sk->sk_state == TCP_CLOSE) + if (sk->sk_state == TCP_CLOSE) { + struct request_sock *req = tcp_sk(sk)->fastopen_rsk; + /* We could get here with a non-NULL req if the socket is + * aborted (e.g., closed with unread data) before 3WHS + * finishes. + */ + if (req != NULL) + reqsk_fastopen_remove(sk, req, false); inet_csk_destroy_sock(sk); + } /* Otherwise, socket is reprieved until protocol close. */ out: @@ -2688,6 +2711,14 @@ static int do_tcp_setsockopt(struct sock *sk, int level, else icsk->icsk_user_timeout = msecs_to_jiffies(val); break; + + case TCP_FASTOPEN: + if (val >= 0 && ((1 << sk->sk_state) & (TCPF_CLOSE | + TCPF_LISTEN))) + err = fastopen_init_queue(sk, val); + else + err = -EINVAL; + break; default: err = -ENOPROTOOPT; break; @@ -3501,11 +3532,15 @@ EXPORT_SYMBOL(tcp_cookie_generator); void tcp_done(struct sock *sk) { + struct request_sock *req = tcp_sk(sk)->fastopen_rsk; + if (sk->sk_state == TCP_SYN_SENT || sk->sk_state == TCP_SYN_RECV) TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_ATTEMPTFAILS); tcp_set_state(sk, TCP_CLOSE); tcp_clear_xmit_timers(sk); + if (req != NULL) + reqsk_fastopen_remove(sk, req, false); sk->sk_shutdown = SHUTDOWN_MASK; diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 36f02f954ac..bb148dee1ed 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -839,7 +839,7 @@ static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst, if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL) return -1; - skb = tcp_make_synack(sk, dst, req, rvp); + skb = tcp_make_synack(sk, dst, req, rvp, NULL); if (skb) { __tcp_v4_send_check(skb, ireq->loc_addr, ireq->rmt_addr); @@ -1554,7 +1554,7 @@ static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) struct request_sock *req = inet_csk_search_req(sk, &prev, th->source, iph->saddr, iph->daddr); if (req) - return tcp_check_req(sk, skb, req, prev); + return tcp_check_req(sk, skb, req, prev, false); nsk = inet_lookup_established(sock_net(sk), &tcp_hashinfo, iph->saddr, th->source, iph->daddr, th->dest, inet_iif(skb)); diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index 6ff7f10dce9..e965319d610 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -507,6 +507,7 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req, newicsk->icsk_ack.last_seg_size = skb->len - newtp->tcp_header_len; newtp->rx_opt.mss_clamp = req->mss; TCP_ECN_openreq_child(newtp, req); + newtp->fastopen_rsk = NULL; TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_PASSIVEOPENS); } @@ -515,13 +516,18 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req, EXPORT_SYMBOL(tcp_create_openreq_child); /* - * Process an incoming packet for SYN_RECV sockets represented - * as a request_sock. + * Process an incoming packet for SYN_RECV sockets represented as a + * request_sock. Normally sk is the listener socket but for TFO it + * points to the child socket. + * + * XXX (TFO) - The current impl contains a special check for ack + * validation and inside tcp_v4_reqsk_send_ack(). Can we do better? */ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, struct request_sock *req, - struct request_sock **prev) + struct request_sock **prev, + bool fastopen) { struct tcp_options_received tmp_opt; const u8 *hash_location; @@ -530,6 +536,8 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, __be32 flg = tcp_flag_word(th) & (TCP_FLAG_RST|TCP_FLAG_SYN|TCP_FLAG_ACK); bool paws_reject = false; + BUG_ON(fastopen == (sk->sk_state == TCP_LISTEN)); + tmp_opt.saw_tstamp = 0; if (th->doff > (sizeof(struct tcphdr)>>2)) { tcp_parse_options(skb, &tmp_opt, &hash_location, 0, NULL); @@ -565,6 +573,9 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, * * Enforce "SYN-ACK" according to figure 8, figure 6 * of RFC793, fixed by RFC1122. + * + * Note that even if there is new data in the SYN packet + * they will be thrown away too. */ req->rsk_ops->rtx_syn_ack(sk, req, NULL); return NULL; @@ -622,9 +633,12 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, * sent (the segment carries an unacceptable ACK) ... * a reset is sent." * - * Invalid ACK: reset will be sent by listening socket + * Invalid ACK: reset will be sent by listening socket. + * Note that the ACK validity check for a Fast Open socket is done + * elsewhere and is checked directly against the child socket rather + * than req because user data may have been sent out. */ - if ((flg & TCP_FLAG_ACK) && + if ((flg & TCP_FLAG_ACK) && !fastopen && (TCP_SKB_CB(skb)->ack_seq != tcp_rsk(req)->snt_isn + 1 + tcp_s_data_size(tcp_sk(sk)))) return sk; @@ -637,7 +651,7 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, /* RFC793: "first check sequence number". */ if (paws_reject || !tcp_in_window(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq, - tcp_rsk(req)->rcv_isn + 1, tcp_rsk(req)->rcv_isn + 1 + req->rcv_wnd)) { + tcp_rsk(req)->rcv_nxt, tcp_rsk(req)->rcv_nxt + req->rcv_wnd)) { /* Out of window: send ACK and drop. */ if (!(flg & TCP_FLAG_RST)) req->rsk_ops->send_ack(sk, skb, req); @@ -648,7 +662,7 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, /* In sequence, PAWS is OK. */ - if (tmp_opt.saw_tstamp && !after(TCP_SKB_CB(skb)->seq, tcp_rsk(req)->rcv_isn + 1)) + if (tmp_opt.saw_tstamp && !after(TCP_SKB_CB(skb)->seq, tcp_rsk(req)->rcv_nxt)) req->ts_recent = tmp_opt.rcv_tsval; if (TCP_SKB_CB(skb)->seq == tcp_rsk(req)->rcv_isn) { @@ -667,10 +681,19 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, /* ACK sequence verified above, just make sure ACK is * set. If ACK not set, just silently drop the packet. + * + * XXX (TFO) - if we ever allow "data after SYN", the + * following check needs to be removed. */ if (!(flg & TCP_FLAG_ACK)) return NULL; + /* For Fast Open no more processing is needed (sk is the + * child socket). + */ + if (fastopen) + return sk; + /* While TCP_DEFER_ACCEPT is active, drop bare ACK. */ if (req->retrans < inet_csk(sk)->icsk_accept_queue.rskq_defer_accept && TCP_SKB_CB(skb)->end_seq == tcp_rsk(req)->rcv_isn + 1) { @@ -706,11 +729,21 @@ listen_overflow: } embryonic_reset: - NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_EMBRYONICRSTS); - if (!(flg & TCP_FLAG_RST)) + if (!(flg & TCP_FLAG_RST)) { + /* Received a bad SYN pkt - for TFO We try not to reset + * the local connection unless it's really necessary to + * avoid becoming vulnerable to outside attack aiming at + * resetting legit local connections. + */ req->rsk_ops->send_reset(sk, skb); - - inet_csk_reqsk_queue_drop(sk, req, prev); + } else if (fastopen) { /* received a valid RST pkt */ + reqsk_fastopen_remove(sk, req, true); + tcp_reset(sk); + } + if (!fastopen) { + inet_csk_reqsk_queue_drop(sk, req, prev); + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_EMBRYONICRSTS); + } return NULL; } EXPORT_SYMBOL(tcp_check_req); @@ -719,6 +752,12 @@ EXPORT_SYMBOL(tcp_check_req); * Queue segment on the new socket if the new socket is active, * otherwise we just shortcircuit this and continue with * the new socket. + * + * For the vast majority of cases child->sk_state will be TCP_SYN_RECV + * when entering. But other states are possible due to a race condition + * where after __inet_lookup_established() fails but before the listener + * locked is obtained, other packets cause the same connection to + * be created. */ int tcp_child_process(struct sock *parent, struct sock *child, diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index d04632673a9..9383b51f3ef 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -702,7 +702,8 @@ static unsigned int tcp_synack_options(struct sock *sk, unsigned int mss, struct sk_buff *skb, struct tcp_out_options *opts, struct tcp_md5sig_key **md5, - struct tcp_extend_values *xvp) + struct tcp_extend_values *xvp, + struct tcp_fastopen_cookie *foc) { struct inet_request_sock *ireq = inet_rsk(req); unsigned int remaining = MAX_TCP_OPTION_SPACE; @@ -747,7 +748,15 @@ static unsigned int tcp_synack_options(struct sock *sk, if (unlikely(!ireq->tstamp_ok)) remaining -= TCPOLEN_SACKPERM_ALIGNED; } - + if (foc != NULL) { + u32 need = TCPOLEN_EXP_FASTOPEN_BASE + foc->len; + need = (need + 3) & ~3U; /* Align to 32 bits */ + if (remaining >= need) { + opts->options |= OPTION_FAST_OPEN_COOKIE; + opts->fastopen_cookie = foc; + remaining -= need; + } + } /* Similar rationale to tcp_syn_options() applies here, too. * If the options fit, the same options should fit now! */ @@ -2658,7 +2667,8 @@ int tcp_send_synack(struct sock *sk) */ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst, struct request_sock *req, - struct request_values *rvp) + struct request_values *rvp, + struct tcp_fastopen_cookie *foc) { struct tcp_out_options opts; struct tcp_extend_values *xvp = tcp_xv(rvp); @@ -2718,7 +2728,7 @@ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst, #endif TCP_SKB_CB(skb)->when = tcp_time_stamp; tcp_header_size = tcp_synack_options(sk, req, mss, - skb, &opts, &md5, xvp) + skb, &opts, &md5, xvp, foc) + sizeof(*th); skb_push(skb, tcp_header_size); @@ -2772,7 +2782,8 @@ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst, } th->seq = htonl(TCP_SKB_CB(skb)->seq); - th->ack_seq = htonl(tcp_rsk(req)->rcv_isn + 1); + /* XXX data is queued and acked as is. No buffer/window check */ + th->ack_seq = htonl(tcp_rsk(req)->rcv_nxt); /* RFC1323: The window in SYN & SYN/ACK segments is never scaled. */ th->window = htons(min(req->rcv_wnd, 65535U)); diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c index b774a03bd1d..fc04711e80c 100644 --- a/net/ipv4/tcp_timer.c +++ b/net/ipv4/tcp_timer.c @@ -304,6 +304,35 @@ static void tcp_probe_timer(struct sock *sk) } } +/* + * Timer for Fast Open socket to retransmit SYNACK. Note that the + * sk here is the child socket, not the parent (listener) socket. + */ +static void tcp_fastopen_synack_timer(struct sock *sk) +{ + struct inet_connection_sock *icsk = inet_csk(sk); + int max_retries = icsk->icsk_syn_retries ? : + sysctl_tcp_synack_retries + 1; /* add one more retry for fastopen */ + struct request_sock *req; + + req = tcp_sk(sk)->fastopen_rsk; + req->rsk_ops->syn_ack_timeout(sk, req); + + if (req->retrans >= max_retries) { + tcp_write_err(sk); + return; + } + /* XXX (TFO) - Unlike regular SYN-ACK retransmit, we ignore error + * returned from rtx_syn_ack() to make it more persistent like + * regular retransmit because if the child socket has been accepted + * it's not good to give up too easily. + */ + req->rsk_ops->rtx_syn_ack(sk, req, NULL); + req->retrans++; + inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, + TCP_TIMEOUT_INIT << req->retrans, TCP_RTO_MAX); +} + /* * The TCP retransmit timer. */ @@ -317,7 +346,15 @@ void tcp_retransmit_timer(struct sock *sk) tcp_resume_early_retransmit(sk); return; } - + if (tp->fastopen_rsk) { + BUG_ON(sk->sk_state != TCP_SYN_RECV && + sk->sk_state != TCP_FIN_WAIT1); + tcp_fastopen_synack_timer(sk); + /* Before we receive ACK to our SYN-ACK don't retransmit + * anything else (e.g., data or FIN segments). + */ + return; + } if (!tp->packets_out) goto out; diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c index bb46061c813..182ab9a85d6 100644 --- a/net/ipv6/syncookies.c +++ b/net/ipv6/syncookies.c @@ -190,6 +190,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb) ireq = inet_rsk(req); ireq6 = inet6_rsk(req); treq = tcp_rsk(req); + treq->listener = NULL; if (security_inet_conn_request(sk, skb, req)) goto out_free; diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index f99b81d53cc..09078b9bc6f 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -475,7 +475,7 @@ static int tcp_v6_send_synack(struct sock *sk, struct dst_entry *dst, if (!dst && (dst = inet6_csk_route_req(sk, fl6, req)) == NULL) goto done; - skb = tcp_make_synack(sk, dst, req, rvp); + skb = tcp_make_synack(sk, dst, req, rvp, NULL); if (skb) { __tcp_v6_send_check(skb, &treq->loc_addr, &treq->rmt_addr); @@ -987,7 +987,7 @@ static struct sock *tcp_v6_hnd_req(struct sock *sk,struct sk_buff *skb) &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr, inet6_iif(skb)); if (req) - return tcp_check_req(sk, skb, req, prev); + return tcp_check_req(sk, skb, req, prev, false); nsk = __inet6_lookup_established(sock_net(sk), &tcp_hashinfo, &ipv6_hdr(skb)->saddr, th->source, @@ -1179,6 +1179,7 @@ have_isn: want_cookie) goto drop_and_free; + tcp_rsk(req)->listener = NULL; inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); return 0; -- cgit v1.2.3-70-g09d2 From 168a8f58059a22feb9e9a2dcc1b8053dbbbc12ef Mon Sep 17 00:00:00 2001 From: Jerry Chu Date: Fri, 31 Aug 2012 12:29:13 +0000 Subject: tcp: TCP Fast Open Server - main code path This patch adds the main processing path to complete the TFO server patches. A TFO request (i.e., SYN+data packet with a TFO cookie option) first gets processed in tcp_v4_conn_request(). If it passes the various TFO checks by tcp_fastopen_check(), a child socket will be created right away to be accepted by applications, rather than waiting for the 3WHS to finish. In additon to the use of TFO cookie, a simple max_qlen based scheme is put in place to fend off spoofed TFO attack. When a valid ACK comes back to tcp_rcv_state_process(), it will cause the state of the child socket to switch from either TCP_SYN_RECV to TCP_ESTABLISHED, or TCP_FIN_WAIT1 to TCP_FIN_WAIT2. At this time retransmission will resume for any unack'ed (data, FIN,...) segments. Signed-off-by: H.K. Jerry Chu Cc: Yuchung Cheng Cc: Neal Cardwell Cc: Eric Dumazet Cc: Tom Herbert Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 71 +++++++++++--- net/ipv4/tcp_ipv4.c | 265 ++++++++++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 309 insertions(+), 27 deletions(-) (limited to 'net/ipv4/tcp_ipv4.c') diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index d47d5fe8f3f..8c304a40079 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3127,6 +3127,12 @@ void tcp_rearm_rto(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); + /* If the retrans timer is currently being used by Fast Open + * for SYN-ACK retrans purpose, stay put. + */ + if (tp->fastopen_rsk) + return; + if (!tp->packets_out) { inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS); } else { @@ -5895,7 +5901,9 @@ discard: tcp_send_synack(sk); #if 0 /* Note, we could accept data and URG from this segment. - * There are no obstacles to make this. + * There are no obstacles to make this (except that we must + * either change tcp_recvmsg() to prevent it from returning data + * before 3WHS completes per RFC793, or employ TCP Fast Open). * * However, if we ignore data in ACKless segments sometimes, * we have no reasons to accept it sometimes. @@ -5935,6 +5943,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb, { struct tcp_sock *tp = tcp_sk(sk); struct inet_connection_sock *icsk = inet_csk(sk); + struct request_sock *req; int queued = 0; tp->rx_opt.saw_tstamp = 0; @@ -5990,7 +5999,14 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb, return 0; } - if (!tcp_validate_incoming(sk, skb, th, 0)) + req = tp->fastopen_rsk; + if (req != NULL) { + BUG_ON(sk->sk_state != TCP_SYN_RECV && + sk->sk_state != TCP_FIN_WAIT1); + + if (tcp_check_req(sk, skb, req, NULL, true) == NULL) + goto discard; + } else if (!tcp_validate_incoming(sk, skb, th, 0)) return 0; /* step 5: check the ACK field */ @@ -6000,7 +6016,22 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb, switch (sk->sk_state) { case TCP_SYN_RECV: if (acceptable) { - tp->copied_seq = tp->rcv_nxt; + /* Once we leave TCP_SYN_RECV, we no longer + * need req so release it. + */ + if (req) { + reqsk_fastopen_remove(sk, req, false); + } else { + /* Make sure socket is routed, for + * correct metrics. + */ + icsk->icsk_af_ops->rebuild_header(sk); + tcp_init_congestion_control(sk); + + tcp_mtup_init(sk); + tcp_init_buffer_space(sk); + tp->copied_seq = tp->rcv_nxt; + } smp_mb(); tcp_set_state(sk, TCP_ESTABLISHED); sk->sk_state_change(sk); @@ -6022,23 +6053,27 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb, if (tp->rx_opt.tstamp_ok) tp->advmss -= TCPOLEN_TSTAMP_ALIGNED; - /* Make sure socket is routed, for - * correct metrics. - */ - icsk->icsk_af_ops->rebuild_header(sk); - - tcp_init_metrics(sk); - - tcp_init_congestion_control(sk); + if (req) { + /* Re-arm the timer because data may + * have been sent out. This is similar + * to the regular data transmission case + * when new data has just been ack'ed. + * + * (TFO) - we could try to be more + * aggressive and retranmitting any data + * sooner based on when they were sent + * out. + */ + tcp_rearm_rto(sk); + } else + tcp_init_metrics(sk); /* Prevent spurious tcp_cwnd_restart() on * first data packet. */ tp->lsndtime = tcp_time_stamp; - tcp_mtup_init(sk); tcp_initialize_rcv_mss(sk); - tcp_init_buffer_space(sk); tcp_fast_path_on(tp); } else { return 1; @@ -6046,6 +6081,16 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb, break; case TCP_FIN_WAIT1: + /* If we enter the TCP_FIN_WAIT1 state and we are a + * Fast Open socket and this is the first acceptable + * ACK we have received, this would have acknowledged + * our SYNACK so stop the SYNACK timer. + */ + if (acceptable && req != NULL) { + /* We no longer need the request sock. */ + reqsk_fastopen_remove(sk, req, false); + tcp_rearm_rto(sk); + } if (tp->snd_una == tp->write_seq) { struct dst_entry *dst; diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index bb148dee1ed..e64abed249c 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -352,6 +352,7 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) const int code = icmp_hdr(icmp_skb)->code; struct sock *sk; struct sk_buff *skb; + struct request_sock *req; __u32 seq; __u32 remaining; int err; @@ -394,9 +395,12 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) icsk = inet_csk(sk); tp = tcp_sk(sk); + req = tp->fastopen_rsk; seq = ntohl(th->seq); if (sk->sk_state != TCP_LISTEN && - !between(seq, tp->snd_una, tp->snd_nxt)) { + !between(seq, tp->snd_una, tp->snd_nxt) && + (req == NULL || seq != tcp_rsk(req)->snt_isn)) { + /* For a Fast Open socket, allow seq to be snt_isn. */ NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); goto out; } @@ -435,6 +439,8 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) !icsk->icsk_backoff) break; + /* XXX (TFO) - revisit the following logic for TFO */ + if (sock_owned_by_user(sk)) break; @@ -466,6 +472,14 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) goto out; } + /* XXX (TFO) - if it's a TFO socket and has been accepted, rather + * than following the TCP_SYN_RECV case and closing the socket, + * we ignore the ICMP error and keep trying like a fully established + * socket. Is this the right thing to do? + */ + if (req && req->sk == NULL) + goto out; + switch (sk->sk_state) { struct request_sock *req, **prev; case TCP_LISTEN: @@ -498,7 +512,8 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) case TCP_SYN_SENT: case TCP_SYN_RECV: /* Cannot happen. - It can f.e. if SYNs crossed. + It can f.e. if SYNs crossed, + or Fast Open. */ if (!sock_owned_by_user(sk)) { sk->sk_err = err; @@ -809,8 +824,12 @@ static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb) static void tcp_v4_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, struct request_sock *req) { - tcp_v4_send_ack(skb, tcp_rsk(req)->snt_isn + 1, - tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, + /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV + * sk->sk_state == TCP_SYN_RECV -> for Fast Open. + */ + tcp_v4_send_ack(skb, (sk->sk_state == TCP_LISTEN) ? + tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt, + tcp_rsk(req)->rcv_nxt, req->rcv_wnd, req->ts_recent, 0, tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&ip_hdr(skb)->daddr, @@ -1272,6 +1291,178 @@ static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { }; #endif +static bool tcp_fastopen_check(struct sock *sk, struct sk_buff *skb, + struct request_sock *req, + struct tcp_fastopen_cookie *foc, + struct tcp_fastopen_cookie *valid_foc) +{ + bool skip_cookie = false; + struct fastopen_queue *fastopenq; + + if (likely(!fastopen_cookie_present(foc))) { + /* See include/net/tcp.h for the meaning of these knobs */ + if ((sysctl_tcp_fastopen & TFO_SERVER_ALWAYS) || + ((sysctl_tcp_fastopen & TFO_SERVER_COOKIE_NOT_REQD) && + (TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq + 1))) + skip_cookie = true; /* no cookie to validate */ + else + return false; + } + fastopenq = inet_csk(sk)->icsk_accept_queue.fastopenq; + /* A FO option is present; bump the counter. */ + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPFASTOPENPASSIVE); + + /* Make sure the listener has enabled fastopen, and we don't + * exceed the max # of pending TFO requests allowed before trying + * to validating the cookie in order to avoid burning CPU cycles + * unnecessarily. + * + * XXX (TFO) - The implication of checking the max_qlen before + * processing a cookie request is that clients can't differentiate + * between qlen overflow causing Fast Open to be disabled + * temporarily vs a server not supporting Fast Open at all. + */ + if ((sysctl_tcp_fastopen & TFO_SERVER_ENABLE) == 0 || + fastopenq == NULL || fastopenq->max_qlen == 0) + return false; + + if (fastopenq->qlen >= fastopenq->max_qlen) { + struct request_sock *req1; + spin_lock(&fastopenq->lock); + req1 = fastopenq->rskq_rst_head; + if ((req1 == NULL) || time_after(req1->expires, jiffies)) { + spin_unlock(&fastopenq->lock); + NET_INC_STATS_BH(sock_net(sk), + LINUX_MIB_TCPFASTOPENLISTENOVERFLOW); + /* Avoid bumping LINUX_MIB_TCPFASTOPENPASSIVEFAIL*/ + foc->len = -1; + return false; + } + fastopenq->rskq_rst_head = req1->dl_next; + fastopenq->qlen--; + spin_unlock(&fastopenq->lock); + reqsk_free(req1); + } + if (skip_cookie) { + tcp_rsk(req)->rcv_nxt = TCP_SKB_CB(skb)->end_seq; + return true; + } + if (foc->len == TCP_FASTOPEN_COOKIE_SIZE) { + if ((sysctl_tcp_fastopen & TFO_SERVER_COOKIE_NOT_CHKED) == 0) { + tcp_fastopen_cookie_gen(ip_hdr(skb)->saddr, valid_foc); + if ((valid_foc->len != TCP_FASTOPEN_COOKIE_SIZE) || + memcmp(&foc->val[0], &valid_foc->val[0], + TCP_FASTOPEN_COOKIE_SIZE) != 0) + return false; + valid_foc->len = -1; + } + /* Acknowledge the data received from the peer. */ + tcp_rsk(req)->rcv_nxt = TCP_SKB_CB(skb)->end_seq; + return true; + } else if (foc->len == 0) { /* Client requesting a cookie */ + tcp_fastopen_cookie_gen(ip_hdr(skb)->saddr, valid_foc); + NET_INC_STATS_BH(sock_net(sk), + LINUX_MIB_TCPFASTOPENCOOKIEREQD); + } else { + /* Client sent a cookie with wrong size. Treat it + * the same as invalid and return a valid one. + */ + tcp_fastopen_cookie_gen(ip_hdr(skb)->saddr, valid_foc); + } + return false; +} + +static int tcp_v4_conn_req_fastopen(struct sock *sk, + struct sk_buff *skb, + struct sk_buff *skb_synack, + struct request_sock *req, + struct request_values *rvp) +{ + struct tcp_sock *tp = tcp_sk(sk); + struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue; + const struct inet_request_sock *ireq = inet_rsk(req); + struct sock *child; + + req->retrans = 0; + req->sk = NULL; + + child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL); + if (child == NULL) { + NET_INC_STATS_BH(sock_net(sk), + LINUX_MIB_TCPFASTOPENPASSIVEFAIL); + kfree_skb(skb_synack); + return -1; + } + ip_build_and_send_pkt(skb_synack, sk, ireq->loc_addr, + ireq->rmt_addr, ireq->opt); + /* XXX (TFO) - is it ok to ignore error and continue? */ + + spin_lock(&queue->fastopenq->lock); + queue->fastopenq->qlen++; + spin_unlock(&queue->fastopenq->lock); + + /* Initialize the child socket. Have to fix some values to take + * into account the child is a Fast Open socket and is created + * only out of the bits carried in the SYN packet. + */ + tp = tcp_sk(child); + + tp->fastopen_rsk = req; + /* Do a hold on the listner sk so that if the listener is being + * closed, the child that has been accepted can live on and still + * access listen_lock. + */ + sock_hold(sk); + tcp_rsk(req)->listener = sk; + + /* RFC1323: The window in SYN & SYN/ACK segments is never + * scaled. So correct it appropriately. + */ + tp->snd_wnd = ntohs(tcp_hdr(skb)->window); + + /* Activate the retrans timer so that SYNACK can be retransmitted. + * The request socket is not added to the SYN table of the parent + * because it's been added to the accept queue directly. + */ + inet_csk_reset_xmit_timer(child, ICSK_TIME_RETRANS, + TCP_TIMEOUT_INIT, TCP_RTO_MAX); + + /* Add the child socket directly into the accept queue */ + inet_csk_reqsk_queue_add(sk, req, child); + + /* Now finish processing the fastopen child socket. */ + inet_csk(child)->icsk_af_ops->rebuild_header(child); + tcp_init_congestion_control(child); + tcp_mtup_init(child); + tcp_init_buffer_space(child); + tcp_init_metrics(child); + + /* Queue the data carried in the SYN packet. We need to first + * bump skb's refcnt because the caller will attempt to free it. + * + * XXX (TFO) - we honor a zero-payload TFO request for now. + * (Any reason not to?) + */ + if (TCP_SKB_CB(skb)->end_seq == TCP_SKB_CB(skb)->seq + 1) { + /* Don't queue the skb if there is no payload in SYN. + * XXX (TFO) - How about SYN+FIN? + */ + tp->rcv_nxt = TCP_SKB_CB(skb)->end_seq; + } else { + skb = skb_get(skb); + skb_dst_drop(skb); + __skb_pull(skb, tcp_hdr(skb)->doff * 4); + skb_set_owner_r(skb, child); + __skb_queue_tail(&child->sk_receive_queue, skb); + tp->rcv_nxt = TCP_SKB_CB(skb)->end_seq; + } + sk->sk_data_ready(sk, 0); + bh_unlock_sock(child); + sock_put(child); + WARN_ON(req->sk == NULL); + return 0; +} + int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) { struct tcp_extend_values tmp_ext; @@ -1285,6 +1476,11 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) __be32 daddr = ip_hdr(skb)->daddr; __u32 isn = TCP_SKB_CB(skb)->when; bool want_cookie = false; + struct flowi4 fl4; + struct tcp_fastopen_cookie foc = { .len = -1 }; + struct tcp_fastopen_cookie valid_foc = { .len = -1 }; + struct sk_buff *skb_synack; + int do_fastopen; /* Never answer to SYNs send to broadcast or multicast */ if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) @@ -1319,7 +1515,8 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) tcp_clear_options(&tmp_opt); tmp_opt.mss_clamp = TCP_MSS_DEFAULT; tmp_opt.user_mss = tp->rx_opt.user_mss; - tcp_parse_options(skb, &tmp_opt, &hash_location, 0, NULL); + tcp_parse_options(skb, &tmp_opt, &hash_location, 0, + want_cookie ? NULL : &foc); if (tmp_opt.cookie_plus > 0 && tmp_opt.saw_tstamp && @@ -1377,8 +1574,6 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) isn = cookie_v4_init_sequence(sk, skb, &req->mss); req->cookie_ts = tmp_opt.tstamp_ok; } else if (!isn) { - struct flowi4 fl4; - /* VJ's idea. We save last timestamp seen * from the destination in peer table, when entering * state TIME-WAIT, and check against it before @@ -1419,14 +1614,52 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) tcp_rsk(req)->snt_isn = isn; tcp_rsk(req)->snt_synack = tcp_time_stamp; - if (tcp_v4_send_synack(sk, dst, req, - (struct request_values *)&tmp_ext, - skb_get_queue_mapping(skb), - want_cookie) || - want_cookie) + if (dst == NULL) { + dst = inet_csk_route_req(sk, &fl4, req); + if (dst == NULL) + goto drop_and_free; + } + do_fastopen = tcp_fastopen_check(sk, skb, req, &foc, &valid_foc); + + /* We don't call tcp_v4_send_synack() directly because we need + * to make sure a child socket can be created successfully before + * sending back synack! + * + * XXX (TFO) - Ideally one would simply call tcp_v4_send_synack() + * (or better yet, call tcp_send_synack() in the child context + * directly, but will have to fix bunch of other code first) + * after syn_recv_sock() except one will need to first fix the + * latter to remove its dependency on the current implementation + * of tcp_v4_send_synack()->tcp_select_initial_window(). + */ + skb_synack = tcp_make_synack(sk, dst, req, + (struct request_values *)&tmp_ext, + fastopen_cookie_present(&valid_foc) ? &valid_foc : NULL); + + if (skb_synack) { + __tcp_v4_send_check(skb_synack, ireq->loc_addr, ireq->rmt_addr); + skb_set_queue_mapping(skb_synack, skb_get_queue_mapping(skb)); + } else + goto drop_and_free; + + if (likely(!do_fastopen)) { + int err; + err = ip_build_and_send_pkt(skb_synack, sk, ireq->loc_addr, + ireq->rmt_addr, ireq->opt); + err = net_xmit_eval(err); + if (err || want_cookie) + goto drop_and_free; + + tcp_rsk(req)->listener = NULL; + /* Add the request_sock to the SYN table */ + inet_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); + if (fastopen_cookie_present(&foc) && foc.len != 0) + NET_INC_STATS_BH(sock_net(sk), + LINUX_MIB_TCPFASTOPENPASSIVEFAIL); + } else if (tcp_v4_conn_req_fastopen(sk, skb, skb_synack, req, + (struct request_values *)&tmp_ext)) goto drop_and_free; - inet_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); return 0; drop_and_release: @@ -1977,6 +2210,7 @@ void tcp_v4_destroy_sock(struct sock *sk) tcp_cookie_values_release); tp->cookie_values = NULL; } + BUG_ON(tp->fastopen_rsk != NULL); /* If socket is aborted during connect operation */ tcp_free_fastopen_req(tp); @@ -2425,6 +2659,7 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i, int *len) const struct tcp_sock *tp = tcp_sk(sk); const struct inet_connection_sock *icsk = inet_csk(sk); const struct inet_sock *inet = inet_sk(sk); + struct fastopen_queue *fastopenq = icsk->icsk_accept_queue.fastopenq; __be32 dest = inet->inet_daddr; __be32 src = inet->inet_rcv_saddr; __u16 destp = ntohs(inet->inet_dport); @@ -2469,7 +2704,9 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i, int *len) jiffies_to_clock_t(icsk->icsk_ack.ato), (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, tp->snd_cwnd, - tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh, + sk->sk_state == TCP_LISTEN ? + (fastopenq ? fastopenq->max_qlen : 0) : + (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh), len); } -- cgit v1.2.3-70-g09d2 From 623df484a777f3c00c1ea3d6a7565b8d8ac688a1 Mon Sep 17 00:00:00 2001 From: Neal Cardwell Date: Sat, 22 Sep 2012 04:18:54 +0000 Subject: tcp: extract code to compute SYNACK RTT In preparation for adding another spot where we compute the SYNACK RTT, extract this code so that it can be shared. Signed-off-by: Neal Cardwell Signed-off-by: David S. Miller --- include/net/tcp.h | 9 +++++++++ net/ipv4/tcp_ipv4.c | 4 +--- net/ipv6/tcp_ipv6.c | 4 +--- 3 files changed, 11 insertions(+), 6 deletions(-) (limited to 'net/ipv4/tcp_ipv4.c') diff --git a/include/net/tcp.h b/include/net/tcp.h index a8cb00c0c6d..a718d0e3d8e 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1137,6 +1137,15 @@ static inline void tcp_openreq_init(struct request_sock *req, ireq->loc_port = tcp_hdr(skb)->dest; } +/* Compute time elapsed between SYNACK and the ACK completing 3WHS */ +static inline void tcp_synack_rtt_meas(struct sock *sk, + struct request_sock *req) +{ + if (tcp_rsk(req)->snt_synack) + tcp_valid_rtt_meas(sk, + tcp_time_stamp - tcp_rsk(req)->snt_synack); +} + extern void tcp_enter_memory_pressure(struct sock *sk); static inline int keepalive_intvl_when(const struct tcp_sock *tp) diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index e64abed249c..1e66f7fb4fe 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1733,9 +1733,7 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb, newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; tcp_initialize_rcv_mss(newsk); - if (tcp_rsk(req)->snt_synack) - tcp_valid_rtt_meas(newsk, - tcp_time_stamp - tcp_rsk(req)->snt_synack); + tcp_synack_rtt_meas(newsk, req); newtp->total_retrans = req->retrans; #ifdef CONFIG_TCP_MD5SIG diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index f3bfb8bbfde..cfeeeb7fcf5 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1348,9 +1348,7 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb, newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; tcp_initialize_rcv_mss(newsk); - if (tcp_rsk(req)->snt_synack) - tcp_valid_rtt_meas(newsk, - tcp_time_stamp - tcp_rsk(req)->snt_synack); + tcp_synack_rtt_meas(newsk, req); newtp->total_retrans = req->retrans; newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6; -- cgit v1.2.3-70-g09d2 From 016818d076871c4ee34db1e8d74dc17ac1de626a Mon Sep 17 00:00:00 2001 From: Neal Cardwell Date: Sat, 22 Sep 2012 04:18:55 +0000 Subject: tcp: TCP Fast Open Server - take SYNACK RTT after completing 3WHS When taking SYNACK RTT samples for servers using TCP Fast Open, fix the code to ensure that we only call tcp_valid_rtt_meas() after we receive the ACK that completes the 3-way handshake. Previously we were always taking an RTT sample in tcp_v4_syn_recv_sock(). However, for TCP Fast Open connections tcp_v4_conn_req_fastopen() calls tcp_v4_syn_recv_sock() at the time we receive the SYN. So for TFO we must wait until tcp_rcv_state_process() to take the RTT sample. To fix this, we wait until after TFO calls tcp_v4_syn_recv_sock() before we set the snt_synack timestamp, since tcp_synack_rtt_meas() already ensures that we only take a SYNACK RTT sample if snt_synack is non-zero. To be careful, we only take a snt_synack timestamp when a SYNACK transmit or retransmit succeeds. Signed-off-by: Neal Cardwell Signed-off-by: David S. Miller --- include/net/tcp.h | 1 + net/ipv4/tcp_input.c | 1 + net/ipv4/tcp_ipv4.c | 12 +++++++++--- net/ipv6/tcp_ipv6.c | 2 +- 4 files changed, 12 insertions(+), 4 deletions(-) (limited to 'net/ipv4/tcp_ipv4.c') diff --git a/include/net/tcp.h b/include/net/tcp.h index a718d0e3d8e..6feeccd83dd 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1125,6 +1125,7 @@ static inline void tcp_openreq_init(struct request_sock *req, req->cookie_ts = 0; tcp_rsk(req)->rcv_isn = TCP_SKB_CB(skb)->seq; tcp_rsk(req)->rcv_nxt = TCP_SKB_CB(skb)->seq + 1; + tcp_rsk(req)->snt_synack = 0; req->mss = rx_opt->mss_clamp; req->ts_recent = rx_opt->saw_tstamp ? rx_opt->rcv_tsval : 0; ireq->tstamp_ok = rx_opt->tstamp_ok; diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index e2bec815ff2..bb326684495 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5983,6 +5983,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb, * need req so release it. */ if (req) { + tcp_synack_rtt_meas(sk, req); reqsk_fastopen_remove(sk, req, false); } else { /* Make sure socket is routed, for diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 1e66f7fb4fe..0a7e020f16b 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -868,6 +868,8 @@ static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst, ireq->rmt_addr, ireq->opt); err = net_xmit_eval(err); + if (!tcp_rsk(req)->snt_synack && !err) + tcp_rsk(req)->snt_synack = tcp_time_stamp; } return err; @@ -1382,6 +1384,7 @@ static int tcp_v4_conn_req_fastopen(struct sock *sk, struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue; const struct inet_request_sock *ireq = inet_rsk(req); struct sock *child; + int err; req->retrans = 0; req->sk = NULL; @@ -1393,8 +1396,11 @@ static int tcp_v4_conn_req_fastopen(struct sock *sk, kfree_skb(skb_synack); return -1; } - ip_build_and_send_pkt(skb_synack, sk, ireq->loc_addr, - ireq->rmt_addr, ireq->opt); + err = ip_build_and_send_pkt(skb_synack, sk, ireq->loc_addr, + ireq->rmt_addr, ireq->opt); + err = net_xmit_eval(err); + if (!err) + tcp_rsk(req)->snt_synack = tcp_time_stamp; /* XXX (TFO) - is it ok to ignore error and continue? */ spin_lock(&queue->fastopenq->lock); @@ -1612,7 +1618,6 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) isn = tcp_v4_init_sequence(skb); } tcp_rsk(req)->snt_isn = isn; - tcp_rsk(req)->snt_synack = tcp_time_stamp; if (dst == NULL) { dst = inet_csk_route_req(sk, &fl4, req); @@ -1650,6 +1655,7 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) if (err || want_cookie) goto drop_and_free; + tcp_rsk(req)->snt_synack = tcp_time_stamp; tcp_rsk(req)->listener = NULL; /* Add the request_sock to the SYN table */ inet_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index cfeeeb7fcf5..d6212d6bc8d 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1169,7 +1169,6 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) } have_isn: tcp_rsk(req)->snt_isn = isn; - tcp_rsk(req)->snt_synack = tcp_time_stamp; if (security_inet_conn_request(sk, skb, req)) goto drop_and_release; @@ -1180,6 +1179,7 @@ have_isn: want_cookie) goto drop_and_free; + tcp_rsk(req)->snt_synack = tcp_time_stamp; tcp_rsk(req)->listener = NULL; inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); return 0; -- cgit v1.2.3-70-g09d2 From 5640f7685831e088fe6c2e1f863a6805962f8e81 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sun, 23 Sep 2012 23:04:42 +0000 Subject: net: use a per task frag allocator We currently use a per socket order-0 page cache for tcp_sendmsg() operations. This page is used to build fragments for skbs. Its done to increase probability of coalescing small write() into single segments in skbs still in write queue (not yet sent) But it wastes a lot of memory for applications handling many mostly idle sockets, since each socket holds one page in sk->sk_sndmsg_page Its also quite inefficient to build TSO 64KB packets, because we need about 16 pages per skb on arches where PAGE_SIZE = 4096, so we hit page allocator more than wanted. This patch adds a per task frag allocator and uses bigger pages, if available. An automatic fallback is done in case of memory pressure. (up to 32768 bytes per frag, thats order-3 pages on x86) This increases TCP stream performance by 20% on loopback device, but also benefits on other network devices, since 8x less frags are mapped on transmit and unmapped on tx completion. Alexander Duyck mentioned a probable performance win on systems with IOMMU enabled. Its possible some SG enabled hardware cant cope with bigger fragments, but their ndo_start_xmit() should already handle this, splitting a fragment in sub fragments, since some arches have PAGE_SIZE=65536 Successfully tested on various ethernet devices. (ixgbe, igb, bnx2x, tg3, mellanox mlx4) Signed-off-by: Eric Dumazet Cc: Ben Hutchings Cc: Vijay Subramanian Cc: Alexander Duyck Tested-by: Vijay Subramanian Signed-off-by: David S. Miller --- include/linux/sched.h | 3 ++ include/net/inet_sock.h | 4 +-- include/net/sock.h | 27 +++++++++-------- kernel/exit.c | 3 ++ kernel/fork.c | 1 + net/core/skbuff.c | 37 ++++++----------------- net/core/sock.c | 49 ++++++++++++++++++++++++++++-- net/ipv4/ip_output.c | 70 ++++++++++++++++++------------------------- net/ipv4/raw.c | 19 +++++++----- net/ipv4/tcp.c | 79 ++++++++++++++----------------------------------- net/ipv4/tcp_ipv4.c | 8 ----- net/ipv6/ip6_output.c | 65 ++++++++++++++++------------------------ net/sched/em_meta.c | 2 +- 13 files changed, 167 insertions(+), 200 deletions(-) (limited to 'net/ipv4/tcp_ipv4.c') diff --git a/include/linux/sched.h b/include/linux/sched.h index b8c86648a2f..a8e2413f6bc 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1530,6 +1530,9 @@ struct task_struct { * cache last used pipe for splice */ struct pipe_inode_info *splice_pipe; + + struct page_frag task_frag; + #ifdef CONFIG_TASK_DELAY_ACCT struct task_delay_info *delays; #endif diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h index 613cfa40167..256c1ed2d69 100644 --- a/include/net/inet_sock.h +++ b/include/net/inet_sock.h @@ -101,10 +101,8 @@ struct inet_cork { __be32 addr; struct ip_options *opt; unsigned int fragsize; - struct dst_entry *dst; int length; /* Total length of all frames */ - struct page *page; - u32 off; + struct dst_entry *dst; u8 tx_flags; }; diff --git a/include/net/sock.h b/include/net/sock.h index 84bdaeca131..f036493b9a6 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -247,8 +247,7 @@ struct cg_proto; * @sk_stamp: time stamp of last packet received * @sk_socket: Identd and reporting IO signals * @sk_user_data: RPC layer private data - * @sk_sndmsg_page: cached page for sendmsg - * @sk_sndmsg_off: cached offset for sendmsg + * @sk_frag: cached page frag * @sk_peek_off: current peek_offset value * @sk_send_head: front of stuff to transmit * @sk_security: used by security modules @@ -362,9 +361,8 @@ struct sock { ktime_t sk_stamp; struct socket *sk_socket; void *sk_user_data; - struct page *sk_sndmsg_page; + struct page_frag sk_frag; struct sk_buff *sk_send_head; - __u32 sk_sndmsg_off; __s32 sk_peek_off; int sk_write_pending; #ifdef CONFIG_SECURITY @@ -2034,18 +2032,23 @@ static inline void sk_stream_moderate_sndbuf(struct sock *sk) struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp); -static inline struct page *sk_stream_alloc_page(struct sock *sk) +/** + * sk_page_frag - return an appropriate page_frag + * @sk: socket + * + * If socket allocation mode allows current thread to sleep, it means its + * safe to use the per task page_frag instead of the per socket one. + */ +static inline struct page_frag *sk_page_frag(struct sock *sk) { - struct page *page = NULL; + if (sk->sk_allocation & __GFP_WAIT) + return ¤t->task_frag; - page = alloc_pages(sk->sk_allocation, 0); - if (!page) { - sk_enter_memory_pressure(sk); - sk_stream_moderate_sndbuf(sk); - } - return page; + return &sk->sk_frag; } +extern bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); + /* * Default write policy as shown to user space via poll/select/SIGIO */ diff --git a/kernel/exit.c b/kernel/exit.c index f65345f9e5b..42f25952edd 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -1046,6 +1046,9 @@ void do_exit(long code) if (tsk->splice_pipe) __free_pipe_info(tsk->splice_pipe); + if (tsk->task_frag.page) + put_page(tsk->task_frag.page); + validate_creds_for_do_exit(tsk); preempt_disable(); diff --git a/kernel/fork.c b/kernel/fork.c index 2c8857e1285..01565b9ce0f 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -330,6 +330,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig) tsk->btrace_seq = 0; #endif tsk->splice_pipe = NULL; + tsk->task_frag.page = NULL; account_kernel_stack(ti, 1); diff --git a/net/core/skbuff.c b/net/core/skbuff.c index fe00d120816..2ede3cfa8ff 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1655,38 +1655,19 @@ static struct page *linear_to_page(struct page *page, unsigned int *len, unsigned int *offset, struct sk_buff *skb, struct sock *sk) { - struct page *p = sk->sk_sndmsg_page; - unsigned int off; + struct page_frag *pfrag = sk_page_frag(sk); - if (!p) { -new_page: - p = sk->sk_sndmsg_page = alloc_pages(sk->sk_allocation, 0); - if (!p) - return NULL; - - off = sk->sk_sndmsg_off = 0; - /* hold one ref to this page until it's full */ - } else { - unsigned int mlen; - - /* If we are the only user of the page, we can reset offset */ - if (page_count(p) == 1) - sk->sk_sndmsg_off = 0; - off = sk->sk_sndmsg_off; - mlen = PAGE_SIZE - off; - if (mlen < 64 && mlen < *len) { - put_page(p); - goto new_page; - } + if (!sk_page_frag_refill(sk, pfrag)) + return NULL; - *len = min_t(unsigned int, *len, mlen); - } + *len = min_t(unsigned int, *len, pfrag->size - pfrag->offset); - memcpy(page_address(p) + off, page_address(page) + *offset, *len); - sk->sk_sndmsg_off += *len; - *offset = off; + memcpy(page_address(pfrag->page) + pfrag->offset, + page_address(page) + *offset, *len); + *offset = pfrag->offset; + pfrag->offset += *len; - return p; + return pfrag->page; } static bool spd_can_coalesce(const struct splice_pipe_desc *spd, diff --git a/net/core/sock.c b/net/core/sock.c index 2693f764922..727114cd6f7 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1744,6 +1744,45 @@ struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, } EXPORT_SYMBOL(sock_alloc_send_skb); +/* On 32bit arches, an skb frag is limited to 2^15 */ +#define SKB_FRAG_PAGE_ORDER get_order(32768) + +bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) +{ + int order; + + if (pfrag->page) { + if (atomic_read(&pfrag->page->_count) == 1) { + pfrag->offset = 0; + return true; + } + if (pfrag->offset < pfrag->size) + return true; + put_page(pfrag->page); + } + + /* We restrict high order allocations to users that can afford to wait */ + order = (sk->sk_allocation & __GFP_WAIT) ? SKB_FRAG_PAGE_ORDER : 0; + + do { + gfp_t gfp = sk->sk_allocation; + + if (order) + gfp |= __GFP_COMP | __GFP_NOWARN; + pfrag->page = alloc_pages(gfp, order); + if (likely(pfrag->page)) { + pfrag->offset = 0; + pfrag->size = PAGE_SIZE << order; + return true; + } + } while (--order >= 0); + + sk_enter_memory_pressure(sk); + sk_stream_moderate_sndbuf(sk); + return false; +} +EXPORT_SYMBOL(sk_page_frag_refill); + static void __lock_sock(struct sock *sk) __releases(&sk->sk_lock.slock) __acquires(&sk->sk_lock.slock) @@ -2173,8 +2212,8 @@ void sock_init_data(struct socket *sock, struct sock *sk) sk->sk_error_report = sock_def_error_report; sk->sk_destruct = sock_def_destruct; - sk->sk_sndmsg_page = NULL; - sk->sk_sndmsg_off = 0; + sk->sk_frag.page = NULL; + sk->sk_frag.offset = 0; sk->sk_peek_off = -1; sk->sk_peer_pid = NULL; @@ -2417,6 +2456,12 @@ void sk_common_release(struct sock *sk) xfrm_sk_free_policy(sk); sk_refcnt_debug_release(sk); + + if (sk->sk_frag.page) { + put_page(sk->sk_frag.page); + sk->sk_frag.page = NULL; + } + sock_put(sk); } EXPORT_SYMBOL(sk_common_release); diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index a5beab1dc95..24a29a39e9a 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -793,6 +793,7 @@ static int __ip_append_data(struct sock *sk, struct flowi4 *fl4, struct sk_buff_head *queue, struct inet_cork *cork, + struct page_frag *pfrag, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int transhdrlen, @@ -987,47 +988,30 @@ alloc_new_skb: } } else { int i = skb_shinfo(skb)->nr_frags; - skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1]; - struct page *page = cork->page; - int off = cork->off; - unsigned int left; - - if (page && (left = PAGE_SIZE - off) > 0) { - if (copy >= left) - copy = left; - if (page != skb_frag_page(frag)) { - if (i == MAX_SKB_FRAGS) { - err = -EMSGSIZE; - goto error; - } - skb_fill_page_desc(skb, i, page, off, 0); - skb_frag_ref(skb, i); - frag = &skb_shinfo(skb)->frags[i]; - } - } else if (i < MAX_SKB_FRAGS) { - if (copy > PAGE_SIZE) - copy = PAGE_SIZE; - page = alloc_pages(sk->sk_allocation, 0); - if (page == NULL) { - err = -ENOMEM; - goto error; - } - cork->page = page; - cork->off = 0; - skb_fill_page_desc(skb, i, page, 0, 0); - frag = &skb_shinfo(skb)->frags[i]; - } else { - err = -EMSGSIZE; - goto error; - } - if (getfrag(from, skb_frag_address(frag)+skb_frag_size(frag), - offset, copy, skb->len, skb) < 0) { - err = -EFAULT; + err = -ENOMEM; + if (!sk_page_frag_refill(sk, pfrag)) goto error; + + if (!skb_can_coalesce(skb, i, pfrag->page, + pfrag->offset)) { + err = -EMSGSIZE; + if (i == MAX_SKB_FRAGS) + goto error; + + __skb_fill_page_desc(skb, i, pfrag->page, + pfrag->offset, 0); + skb_shinfo(skb)->nr_frags = ++i; + get_page(pfrag->page); } - cork->off += copy; - skb_frag_size_add(frag, copy); + copy = min_t(int, copy, pfrag->size - pfrag->offset); + if (getfrag(from, + page_address(pfrag->page) + pfrag->offset, + offset, copy, skb->len, skb) < 0) + goto error_efault; + + pfrag->offset += copy; + skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy); skb->len += copy; skb->data_len += copy; skb->truesize += copy; @@ -1039,6 +1023,8 @@ alloc_new_skb: return 0; +error_efault: + err = -EFAULT; error: cork->length -= length; IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTDISCARDS); @@ -1079,8 +1065,6 @@ static int ip_setup_cork(struct sock *sk, struct inet_cork *cork, cork->dst = &rt->dst; cork->length = 0; cork->tx_flags = ipc->tx_flags; - cork->page = NULL; - cork->off = 0; return 0; } @@ -1117,7 +1101,8 @@ int ip_append_data(struct sock *sk, struct flowi4 *fl4, transhdrlen = 0; } - return __ip_append_data(sk, fl4, &sk->sk_write_queue, &inet->cork.base, getfrag, + return __ip_append_data(sk, fl4, &sk->sk_write_queue, &inet->cork.base, + sk_page_frag(sk), getfrag, from, length, transhdrlen, flags); } @@ -1439,7 +1424,8 @@ struct sk_buff *ip_make_skb(struct sock *sk, if (err) return ERR_PTR(err); - err = __ip_append_data(sk, fl4, &queue, &cork, getfrag, + err = __ip_append_data(sk, fl4, &queue, &cork, + ¤t->task_frag, getfrag, from, length, transhdrlen, flags); if (err) { __ip_flush_pending_frames(sk, &queue, &cork); diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index f2425785d40..a80740ba424 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -131,18 +131,23 @@ found: * 0 - deliver * 1 - block */ -static __inline__ int icmp_filter(struct sock *sk, struct sk_buff *skb) +static int icmp_filter(const struct sock *sk, const struct sk_buff *skb) { - int type; - - if (!pskb_may_pull(skb, sizeof(struct icmphdr))) + struct icmphdr _hdr; + const struct icmphdr *hdr; + + pr_err("icmp_filter skb_transport_offset %d data-head %ld len %d/%d\n", + skb_transport_offset(skb), skb->data - skb->head, skb->len, skb->data_len); + hdr = skb_header_pointer(skb, skb_transport_offset(skb), + sizeof(_hdr), &_hdr); + pr_err("head %p data %p hdr %p type %d\n", skb->head, skb->data, hdr, hdr ? hdr->type : -1); + if (!hdr) return 1; - type = icmp_hdr(skb)->type; - if (type < 32) { + if (hdr->type < 32) { __u32 data = raw_sk(sk)->filter.data; - return ((1 << type) & data) != 0; + return ((1U << hdr->type) & data) != 0; } /* Do not block unknown ICMP types */ diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 7b1e940393c..72ea4752f21 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1150,78 +1150,43 @@ new_segment: if (err) goto do_fault; } else { - bool merge = false; + bool merge = true; int i = skb_shinfo(skb)->nr_frags; - struct page *page = sk->sk_sndmsg_page; - int off; - - if (page && page_count(page) == 1) - sk->sk_sndmsg_off = 0; - - off = sk->sk_sndmsg_off; - - if (skb_can_coalesce(skb, i, page, off) && - off != PAGE_SIZE) { - /* We can extend the last page - * fragment. */ - merge = true; - } else if (i == MAX_SKB_FRAGS || !sg) { - /* Need to add new fragment and cannot - * do this because interface is non-SG, - * or because all the page slots are - * busy. */ - tcp_mark_push(tp, skb); - goto new_segment; - } else if (page) { - if (off == PAGE_SIZE) { - put_page(page); - sk->sk_sndmsg_page = page = NULL; - off = 0; + struct page_frag *pfrag = sk_page_frag(sk); + + if (!sk_page_frag_refill(sk, pfrag)) + goto wait_for_memory; + + if (!skb_can_coalesce(skb, i, pfrag->page, + pfrag->offset)) { + if (i == MAX_SKB_FRAGS || !sg) { + tcp_mark_push(tp, skb); + goto new_segment; } - } else - off = 0; + merge = false; + } - if (copy > PAGE_SIZE - off) - copy = PAGE_SIZE - off; + copy = min_t(int, copy, pfrag->size - pfrag->offset); if (!sk_wmem_schedule(sk, copy)) goto wait_for_memory; - if (!page) { - /* Allocate new cache page. */ - if (!(page = sk_stream_alloc_page(sk))) - goto wait_for_memory; - } - - /* Time to copy data. We are close to - * the end! */ err = skb_copy_to_page_nocache(sk, from, skb, - page, off, copy); - if (err) { - /* If this page was new, give it to the - * socket so it does not get leaked. - */ - if (!sk->sk_sndmsg_page) { - sk->sk_sndmsg_page = page; - sk->sk_sndmsg_off = 0; - } + pfrag->page, + pfrag->offset, + copy); + if (err) goto do_error; - } /* Update the skb. */ if (merge) { skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy); } else { - skb_fill_page_desc(skb, i, page, off, copy); - if (sk->sk_sndmsg_page) { - get_page(page); - } else if (off + copy < PAGE_SIZE) { - get_page(page); - sk->sk_sndmsg_page = page; - } + skb_fill_page_desc(skb, i, pfrag->page, + pfrag->offset, copy); + get_page(pfrag->page); } - - sk->sk_sndmsg_off = off + copy; + pfrag->offset += copy; } if (!copied) diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 0a7e020f16b..93406c583f4 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2200,14 +2200,6 @@ void tcp_v4_destroy_sock(struct sock *sk) if (inet_csk(sk)->icsk_bind_hash) inet_put_port(sk); - /* - * If sendmsg cached page exists, toss it. - */ - if (sk->sk_sndmsg_page) { - __free_page(sk->sk_sndmsg_page); - sk->sk_sndmsg_page = NULL; - } - /* TCP Cookie Transactions */ if (tp->cookie_values != NULL) { kref_put(&tp->cookie_values->kref, diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 3dd4a37488d..aece3e792f8 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1279,8 +1279,6 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to, if (dst_allfrag(rt->dst.path)) cork->flags |= IPCORK_ALLFRAG; cork->length = 0; - sk->sk_sndmsg_page = NULL; - sk->sk_sndmsg_off = 0; exthdrlen = (opt ? opt->opt_flen : 0) - rt->rt6i_nfheader_len; length += exthdrlen; transhdrlen += exthdrlen; @@ -1504,48 +1502,31 @@ alloc_new_skb: } } else { int i = skb_shinfo(skb)->nr_frags; - skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1]; - struct page *page = sk->sk_sndmsg_page; - int off = sk->sk_sndmsg_off; - unsigned int left; - - if (page && (left = PAGE_SIZE - off) > 0) { - if (copy >= left) - copy = left; - if (page != skb_frag_page(frag)) { - if (i == MAX_SKB_FRAGS) { - err = -EMSGSIZE; - goto error; - } - skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0); - skb_frag_ref(skb, i); - frag = &skb_shinfo(skb)->frags[i]; - } - } else if(i < MAX_SKB_FRAGS) { - if (copy > PAGE_SIZE) - copy = PAGE_SIZE; - page = alloc_pages(sk->sk_allocation, 0); - if (page == NULL) { - err = -ENOMEM; - goto error; - } - sk->sk_sndmsg_page = page; - sk->sk_sndmsg_off = 0; + struct page_frag *pfrag = sk_page_frag(sk); - skb_fill_page_desc(skb, i, page, 0, 0); - frag = &skb_shinfo(skb)->frags[i]; - } else { - err = -EMSGSIZE; + err = -ENOMEM; + if (!sk_page_frag_refill(sk, pfrag)) goto error; + + if (!skb_can_coalesce(skb, i, pfrag->page, + pfrag->offset)) { + err = -EMSGSIZE; + if (i == MAX_SKB_FRAGS) + goto error; + + __skb_fill_page_desc(skb, i, pfrag->page, + pfrag->offset, 0); + skb_shinfo(skb)->nr_frags = ++i; + get_page(pfrag->page); } + copy = min_t(int, copy, pfrag->size - pfrag->offset); if (getfrag(from, - skb_frag_address(frag) + skb_frag_size(frag), - offset, copy, skb->len, skb) < 0) { - err = -EFAULT; - goto error; - } - sk->sk_sndmsg_off += copy; - skb_frag_size_add(frag, copy); + page_address(pfrag->page) + pfrag->offset, + offset, copy, skb->len, skb) < 0) + goto error_efault; + + pfrag->offset += copy; + skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy); skb->len += copy; skb->data_len += copy; skb->truesize += copy; @@ -1554,7 +1535,11 @@ alloc_new_skb: offset += copy; length -= copy; } + return 0; + +error_efault: + err = -EFAULT; error: cork->length -= length; IP6_INC_STATS(sock_net(sk), rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS); diff --git a/net/sched/em_meta.c b/net/sched/em_meta.c index 4ab6e332557..7c3de6ffa51 100644 --- a/net/sched/em_meta.c +++ b/net/sched/em_meta.c @@ -461,7 +461,7 @@ META_COLLECTOR(int_sk_sndtimeo) META_COLLECTOR(int_sk_sendmsg_off) { SKIP_NONLOCAL(skb); - dst->value = skb->sk->sk_sndmsg_off; + dst->value = skb->sk->sk_frag.offset; } META_COLLECTOR(int_sk_write_pend) -- cgit v1.2.3-70-g09d2 From 5dff747b7038d10f9c174a1245263fd1c36a644d Mon Sep 17 00:00:00 2001 From: Christoph Paasch Date: Wed, 26 Sep 2012 11:59:09 +0000 Subject: tcp: Remove unused parameter from tcp_v4_save_options struct sock *sk is not used inside tcp_v4_save_options. Thus it can be removed. Signed-off-by: Christoph Paasch Signed-off-by: David S. Miller --- net/ipv4/tcp_ipv4.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'net/ipv4/tcp_ipv4.c') diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 93406c583f4..385eb79cf6a 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -925,8 +925,7 @@ EXPORT_SYMBOL(tcp_syn_flood_action); /* * Save and compile IPv4 options into the request_sock if needed. */ -static struct ip_options_rcu *tcp_v4_save_options(struct sock *sk, - struct sk_buff *skb) +static struct ip_options_rcu *tcp_v4_save_options(struct sk_buff *skb) { const struct ip_options *opt = &(IPCB(skb)->opt); struct ip_options_rcu *dopt = NULL; @@ -1568,7 +1567,7 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) ireq->loc_addr = daddr; ireq->rmt_addr = saddr; ireq->no_srccheck = inet_sk(sk)->transparent; - ireq->opt = tcp_v4_save_options(sk, skb); + ireq->opt = tcp_v4_save_options(skb); if (security_inet_conn_request(sk, skb, req)) goto drop_and_free; -- cgit v1.2.3-70-g09d2 From 861b650101eb0c627d171eb18de81dddb93d395e Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 27 Sep 2012 02:14:53 +0000 Subject: tcp: gro: add checksuming helpers skb with CHECKSUM_NONE cant currently be handled by GRO, and we notice this deep in GRO stack in tcp[46]_gro_receive() But there are cases where GRO can be a benefit, even with a lack of checksums. This preliminary work is needed to add GRO support to tunnels. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/tcp_ipv4.c | 19 ++++++++++++++++--- net/ipv6/tcp_ipv6.c | 20 +++++++++++++++++--- 2 files changed, 33 insertions(+), 6 deletions(-) (limited to 'net/ipv4/tcp_ipv4.c') diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 385eb79cf6a..75735c9a6a9 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2803,6 +2803,8 @@ void tcp4_proc_exit(void) struct sk_buff **tcp4_gro_receive(struct sk_buff **head, struct sk_buff *skb) { const struct iphdr *iph = skb_gro_network_header(skb); + __wsum wsum; + __sum16 sum; switch (skb->ip_summed) { case CHECKSUM_COMPLETE: @@ -2811,11 +2813,22 @@ struct sk_buff **tcp4_gro_receive(struct sk_buff **head, struct sk_buff *skb) skb->ip_summed = CHECKSUM_UNNECESSARY; break; } - - /* fall through */ - case CHECKSUM_NONE: +flush: NAPI_GRO_CB(skb)->flush = 1; return NULL; + + case CHECKSUM_NONE: + wsum = csum_tcpudp_nofold(iph->saddr, iph->daddr, + skb_gro_len(skb), IPPROTO_TCP, 0); + sum = csum_fold(skb_checksum(skb, + skb_gro_offset(skb), + skb_gro_len(skb), + wsum)); + if (sum) + goto flush; + + skb->ip_summed = CHECKSUM_UNNECESSARY; + break; } return tcp_gro_receive(head, skb); diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index d6212d6bc8d..49c890386ce 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -763,6 +763,8 @@ static struct sk_buff **tcp6_gro_receive(struct sk_buff **head, struct sk_buff *skb) { const struct ipv6hdr *iph = skb_gro_network_header(skb); + __wsum wsum; + __sum16 sum; switch (skb->ip_summed) { case CHECKSUM_COMPLETE: @@ -771,11 +773,23 @@ static struct sk_buff **tcp6_gro_receive(struct sk_buff **head, skb->ip_summed = CHECKSUM_UNNECESSARY; break; } - - /* fall through */ - case CHECKSUM_NONE: +flush: NAPI_GRO_CB(skb)->flush = 1; return NULL; + + case CHECKSUM_NONE: + wsum = ~csum_unfold(csum_ipv6_magic(&iph->saddr, &iph->daddr, + skb_gro_len(skb), + IPPROTO_TCP, 0)); + sum = csum_fold(skb_checksum(skb, + skb_gro_offset(skb), + skb_gro_len(skb), + wsum)); + if (sum) + goto flush; + + skb->ip_summed = CHECKSUM_UNNECESSARY; + break; } return tcp_gro_receive(head, skb); -- cgit v1.2.3-70-g09d2