rds: tcp: misc bug fixes
Subsystems (3)
cover rds: tcp: misc bug fixes
This series contains 2 bug fixes (patch2, patch3) and one bit of code cleanup (patch1) identified during database testing
Sowmini Varadhan (3):
rds: tcp: remove cp_outgoing
rds: tcp: various endian-ness fixes
rds: tcp: Set linger when rejecting an incoming conn in
rds_tcp_accept_one
net/rds/connection.c | 5 ----- net/rds/rds.h | 4 ++-- net/rds/recv.c | 12 +++++++----- net/rds/send.c | 11 +++++++---- net/rds/tcp_connect.c | 3 +-- net/rds/tcp_listen.c | 40 +++++++++++++++++++++++----------------- net/rds/threads.c | 5 +++-- 7 files changed, 43 insertions(+), 37 deletions(-)
PATCH 1/3 rds: tcp: remove cp_outgoing
After commit 1a0e100fb2c9 ("RDS: TCP: Force every connection to be initiated by numerically smaller IP address") we no longer need the logic associated with cp_outgoing, so clean up usage of this field.
Signed-off-by Sowmini Varadhan <[email protected]>
Tested-by Imanti Mendez <[email protected]>
--- net/rds/connection.c | 5 ----- net/rds/rds.h | 2 -- net/rds/tcp_connect.c | 1 - net/rds/tcp_listen.c | 19 ++++--------------- 4 files changed, 4 insertions(+), 23 deletions(-)
net/rds/connection.c +0 -5
@@ -124,11 +124,6 @@ static void __rds_conn_path_init(struct rds_connection *conn, cp->cp_conn = conn;atomic_set (&cp->cp_state,RDS_CONN_DOWN ); cp->cp_send_gen =0 ; -/* cp_outgoing is per-path. So we can only set it here -* for the single-path transports. -*/ -if (!conn->c_trans->t_mp_capable) - cp->cp_outgoing = (is_outgoing ?1 :0 ); cp->cp_reconnect_jiffies =0 ;INIT_DELAYED_WORK (&cp->cp_send_w, rds_send_worker);INIT_DELAYED_WORK (&cp->cp_recv_w, rds_recv_worker);
net/rds/rds.h +0 -2
@@ -125,8 +125,6 @@ struct rds_conn_path {unsigned int cp_unacked_packets;unsigned int cp_unacked_bytes; - unsigned int cp_outgoing:1, - cp_pad_to_32:31;unsigned int cp_index; };
net/rds/tcp_connect.c +0 -1
@@ -135,7 +135,6 @@ int rds_tcp_conn_path_connect(struct rds_conn_path *cp) ret = sock->ops->connect (sock, (struct sockaddr *)&dest,sizeof (dest),O_NONBLOCK ); - cp->cp_outgoing =1 ;rdsdebug ("connect to address %pI4 returned %d\n" , &conn->c_faddr, ret);if (ret == -EINPROGRESS ) ret =0 ;
net/rds/tcp_listen.c +4 -15
@@ -171,21 +171,10 @@ int rds_tcp_accept_one(struct socket *sock)if (conn_state !=RDS_CONN_CONNECTING && conn_state !=RDS_CONN_ERROR ) goto rst_nsk;if (rs_tcp->t_sock) { -/* Need to resolve a duelling SYN between peers. -* We have an outstanding SYN to this peer, which may -* potentially have transitioned to the RDS_CONN_UP state, -* so we must quiesce any send threads before resetting -* c_transport_data. -*/ -if (ntohl (inet->inet_saddr) <ntohl (inet->inet_daddr) || - !cp->cp_outgoing) { - goto rst_nsk; - }else { -rds_tcp_reset_callbacks (new_sock, cp); - cp->cp_outgoing =0 ; -/* rds_connect_path_complete() marks RDS_CONN_UP */ -rds_connect_path_complete (cp,RDS_CONN_RESETTING ); - } +/* Duelling SYN has been handled in rds_tcp_accept_one() */ +rds_tcp_reset_callbacks (new_sock, cp); +/* rds_connect_path_complete() marks RDS_CONN_UP */ +rds_connect_path_complete (cp,RDS_CONN_RESETTING ); }else {rds_tcp_set_callbacks (new_sock, cp);rds_connect_path_complete (cp,RDS_CONN_CONNECTING );
Signature · 1 line
1.7.1
PATCH 2/3 rds: tcp: various endian-ness fixes
In reply to Sowmini VaradhanFound when testing between sparc and x86 machines on different subnets, so the address comparison patterns hit the corner cases and brought out some bugs fixed by this patch.
Signed-off-by Sowmini Varadhan <[email protected]>
Tested-by Imanti Mendez <[email protected]>
--- net/rds/rds.h | 2 ++ net/rds/recv.c | 12 +++++++----- net/rds/send.c | 11 +++++++---- net/rds/tcp_connect.c | 2 +- net/rds/tcp_listen.c | 2 +- net/rds/threads.c | 5 +++-- 6 files changed, 21 insertions(+), 13 deletions(-)
net/rds/rds.h +2 -0
@@ -92,6 +92,8 @@ enum {#define RDS_MPATH_HASH (rs, n) (jhash_1word((rs)->rs_bound_port, \ (rs)->rs_hash_initval) & ((n) - 1)) +#define IS_CANONICAL (laddr, faddr) (htonl(laddr) < htonl(faddr)) +/* Per mpath connection state */ struct rds_conn_path {struct rds_connection *cp_conn;
net/rds/recv.c +7 -5
@@ -215,10 +215,10 @@ static void rds_recv_hs_exthdrs(struct rds_header *hdr,switch (type) {case RDS_EXTHDR_NPATHS : conn->c_npaths =min_t (int,RDS_MPATH_WORKERS , - buffer.rds_npaths); +be16_to_cpu (buffer.rds_npaths));break ;case RDS_EXTHDR_GEN_NUM : - new_peer_gen_num = buffer.rds_gen_num; + new_peer_gen_num =be32_to_cpu (buffer.rds_gen_num);break ;default : pr_warn_ratelimited("ignoring unknown exthdr type "
@@ -254,7 +254,8 @@ static void rds_start_mprds(struct rds_connection *conn)int i;struct rds_conn_path *cp; -if (conn->c_npaths >1 && conn->c_laddr < conn->c_faddr) { +if (conn->c_npaths >1 && +IS_CANONICAL (conn->c_laddr, conn->c_faddr)) {for (i =1 ; i < conn->c_npaths; i++) { cp = &conn->c_path[i];rds_conn_path_connect_if_down (cp);
@@ -339,14 +340,15 @@ void rds_recv_incoming(struct rds_connection *conn, __be32 saddr, __be32 daddr,rds_stats_inc (s_recv_ping);rds_send_pong (cp, inc->i_hdr.h_sport);/* if this is a handshake ping, start multipath if necessary */ -if (RDS_HS_PROBE (inc->i_hdr.h_sport, inc->i_hdr.h_dport)) { +if (RDS_HS_PROBE (be16_to_cpu (inc->i_hdr.h_sport), +be16_to_cpu (inc->i_hdr.h_dport))) {rds_recv_hs_exthdrs (&inc->i_hdr, cp->cp_conn);rds_start_mprds (cp->cp_conn); } goto out; } -if (inc->i_hdr.h_dport ==RDS_FLAG_PROBE_PORT && +if (be16_to_cpu (inc->i_hdr.h_dport) ==RDS_FLAG_PROBE_PORT && inc->i_hdr.h_sport ==0 ) {rds_recv_hs_exthdrs (&inc->i_hdr, cp->cp_conn);/* if this is a handshake pong, start multipath if necessary */
net/rds/send.c +7 -4
@@ -1246,15 +1246,17 @@ int rds_sendmsg(struct socket *sock, struct msghdr *msg, size_t payload_len) rm->m_inc.i_hdr.h_flags |= h_flags; cp->cp_next_tx_seq++; -if (RDS_HS_PROBE (sport, dport) && cp->cp_conn->c_trans->t_mp_capable) { -u16 npaths =RDS_MPATH_WORKERS ; +if (RDS_HS_PROBE (be16_to_cpu (sport),be16_to_cpu (dport)) && + cp->cp_conn->c_trans->t_mp_capable) { +u16 npaths =cpu_to_be16 (RDS_MPATH_WORKERS ); +u32 my_gen_num =cpu_to_be32 (cp->cp_conn->c_my_gen_num);rds_message_add_extension (&rm->m_inc.i_hdr,RDS_EXTHDR_NPATHS , &npaths,sizeof (npaths));rds_message_add_extension (&rm->m_inc.i_hdr,RDS_EXTHDR_GEN_NUM , - &cp->cp_conn->c_my_gen_num, + &my_gen_num,sizeof (u32)); }spin_unlock_irqrestore (&cp->cp_lock, flags);
@@ -1293,5 +1295,6 @@ int rds_sendmsg(struct socket *sock, struct msghdr *msg, size_t payload_len) } conn->c_ping_triggered =1 ;spin_unlock_irqrestore (&cp->cp_lock, flags); -rds_send_probe (&conn->c_path[0 ],RDS_FLAG_PROBE_PORT ,0 ,0 ); +rds_send_probe (&conn->c_path[0 ],cpu_to_be16 (RDS_FLAG_PROBE_PORT ), +0 ,0 ); }
net/rds/tcp_connect.c +1 -1
@@ -66,7 +66,7 @@ void rds_tcp_state_change(struct sock *sk)* RDS connection as RDS_CONN_UP until the reconnect, * to avoid RDS datagram loss. */ -if (cp->cp_conn->c_laddr > cp->cp_conn->c_faddr && +if (!IS_CANONICAL (cp->cp_conn->c_laddr, cp->cp_conn->c_faddr) &&rds_conn_path_transition (cp,RDS_CONN_CONNECTING ,RDS_CONN_ERROR )) {rds_conn_path_drop (cp);
net/rds/tcp_listen.c +1 -1
@@ -83,7 +83,7 @@ int rds_tcp_keepalive(struct socket *sock)struct rds_tcp_connection *rds_tcp_accept_one_path (struct rds_connection *conn) {int i; -bool peer_is_smaller = (conn->c_faddr < conn->c_laddr); +bool peer_is_smaller =IS_CANONICAL (conn->c_faddr, conn->c_laddr);int npaths =max_t (int,1 , conn->c_npaths);/* for mprds, all paths MUST be initiated by the peer
net/rds/threads.c +3 -2
@@ -127,7 +127,7 @@ void rds_queue_reconnect(struct rds_conn_path *cp)/* let peer with smaller addr initiate reconnect, to avoid duels */ if (conn->c_trans->t_type ==RDS_TRANS_TCP && - conn->c_laddr > conn->c_faddr) + !IS_CANONICAL (conn->c_laddr, conn->c_faddr))return ;set_bit (RDS_RECONNECT_PENDING , &cp->cp_flags);
@@ -156,7 +156,8 @@ void rds_connect_worker(struct work_struct *work)struct rds_connection *conn = cp->cp_conn;int ret; -if (cp->cp_index >0 && cp->cp_conn->c_laddr > cp->cp_conn->c_faddr) +if (cp->cp_index >0 && + !IS_CANONICAL (cp->cp_conn->c_laddr, cp->cp_conn->c_faddr))return ;clear_bit (RDS_RECONNECT_PENDING , &cp->cp_flags); ret =rds_conn_path_transition (cp,RDS_CONN_DOWN ,RDS_CONN_CONNECTING );
Signature · 1 line
1.7.1
PATCH 3/3 rds: tcp: Set linger when rejecting an incoming conn in rds_tcp_accept_one
In reply to Sowmini VaradhanEach time we get an incoming SYN to the RDS_TCP_PORT, the TCP layer accepts the connection and then the rds_tcp_accept_one() callback is invoked to process the incoming connection.
rds_tcp_accept_one() may reject the incoming syn for a number of reasons, e.g., commit 1a0e100fb2c9 ("RDS: TCP: Force every connection to be initiated by numerically smaller IP address"), or because we are getting spammed by a malicious node that is triggering a flood of connection attempts to RDS_TCP_PORT. If the incoming syn is rejected, no data would have been sent on the TCP socket, and we do not need to be in TIME_WAIT state, so we set linger on the TCP socket before closing, thereby closing the socket efficiently with a RST.
Signed-off-by Sowmini Varadhan <[email protected]>
Tested-by Imanti Mendez <[email protected]>
--- net/rds/tcp_listen.c | 19 ++++++++++++++++++- 1 files changed, 18 insertions(+), 1 deletions(-)
net/rds/tcp_listen.c +18 -1
@@ -112,6 +112,17 @@ struct rds_tcp_connection *rds_tcp_accept_one_path(struct rds_connection *conn)return NULL ; } +static void rds_tcp_set_linger (struct socket *sock) +{ +struct linger no_linger = { + .l_onoff =1 , + .l_linger =0 , + }; + +kernel_setsockopt (sock,SOL_SOCKET ,SO_LINGER , + (char *)&no_linger,sizeof (no_linger)); +} +int rds_tcp_accept_one (struct socket *sock) {struct socket *new_sock =NULL ;
@@ -183,7 +194,13 @@ int rds_tcp_accept_one(struct socket *sock) ret =0 ; goto out; rst_nsk: -/* reset the newly returned accept sock and bail */ +/* reset the newly returned accept sock and bail. +* It is safe to set linger on new_sock because the RDS connection +* has not been brought up on new_sock, so no RDS-level data could +* be pending on it. By setting linger, we achieve the side-effect +* of avoiding TIME_WAIT state on new_sock. +*/ +rds_tcp_set_linger (new_sock);kernel_sock_shutdown (new_sock,SHUT_RDWR ); ret =0 ; out:
Signature · 1 line
1.7.1
David Miller
maintainerFrom: Sowmini Varadhan <[email protected]>
Date: Thu, 15 Jun 2017 11:28:52 -0700
Quoted 2 lines
This series contains 2 bug fixes (patch2, patch3) and one bit of code cleanup (patch1) identified during database testing
Series applied, thank you.