From: Ursula Braun <ubraun@linux.ibm.com> mainline inclusion from mainline-v5.1-rc6 commit 07603b230895a74ebb1e2a1231ac45c29c2a8cd3 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IC4DSN Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- fcntl(fd, F_SETOWN, getpid()) selects the recipient of SIGURG signals that are delivered when out-of-band data arrives on socket fd. If an SMC socket program makes use of such an fcntl() call, it fails in case of fallback to TCP-mode. In case of fallback the traffic is processed with the internal TCP socket. Propagating field "file" from the SMC socket to the internal TCP socket fixes the issue. Reviewed-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: Ursula Braun <ubraun@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Wang Liang <wangliang74@huawei.com> --- include/net/sock.h | 6 ------ net/smc/af_smc.c | 38 ++++++++++++++++++++++++++++---------- 2 files changed, 28 insertions(+), 16 deletions(-) diff --git a/include/net/sock.h b/include/net/sock.h index cdb991e633cf..1840303a5539 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -2172,12 +2172,6 @@ static inline bool skwq_has_sleeper(struct socket_wq *wq) * @p: poll_table * * See the comments in the wq_has_sleeper function. - * - * Do not derive sock from filp->private_data here. An SMC socket establishes - * an internal TCP socket that is used in the fallback case. All socket - * operations on the SMC socket are then forwarded to the TCP socket. In case of - * poll, the filp->private_data pointer references the SMC socket because the - * TCP socket has no file assigned. */ static inline void sock_poll_wait(struct file *filp, struct socket *sock, poll_table *p) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 26dcd02b2d0c..13b9f4cfb45a 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -432,10 +432,19 @@ static void smc_link_save_peer_info(struct smc_link *link, link->peer_mtu = clc->qp_mtu; } +static void smc_switch_to_fallback(struct smc_sock *smc) +{ + smc->use_fallback = true; + if (smc->sk.sk_socket && smc->sk.sk_socket->file) { + smc->clcsock->file = smc->sk.sk_socket->file; + smc->clcsock->file->private_data = smc->clcsock; + } +} + /* fall back during connect */ static int smc_connect_fallback(struct smc_sock *smc, int reason_code) { - smc->use_fallback = true; + smc_switch_to_fallback(smc); smc->fallback_rsn = reason_code; smc_copy_sock_settings_to_clc(smc); if (smc->sk.sk_state == SMC_INIT) @@ -751,10 +760,14 @@ static void smc_connect_work(struct work_struct *work) smc->sk.sk_err = -rc; out: - if (smc->sk.sk_err) - smc->sk.sk_state_change(&smc->sk); - else - smc->sk.sk_write_space(&smc->sk); + if (!sock_flag(&smc->sk, SOCK_DEAD)) { + if (smc->sk.sk_err) { + smc->sk.sk_state_change(&smc->sk); + } else { /* allow polling before and after fallback decision */ + smc->clcsock->sk->sk_write_space(smc->clcsock->sk); + smc->sk.sk_write_space(&smc->sk); + } + } kfree(smc->connect_info); smc->connect_info = NULL; release_sock(&smc->sk); @@ -911,8 +924,13 @@ struct sock *smc_accept_dequeue(struct sock *parent, sock_put(new_sk); /* final */ continue; } - if (new_sock) + if (new_sock) { sock_graft(new_sk, new_sock); + if (isk->use_fallback) { + smc_sk(new_sk)->clcsock->file = new_sock->file; + isk->clcsock->file->private_data = isk->clcsock; + } + } return new_sk; } return NULL; @@ -1063,7 +1081,7 @@ static void smc_listen_decline(struct smc_sock *new_smc, int reason_code, return; } smc_conn_free(&new_smc->conn); - new_smc->use_fallback = true; + smc_switch_to_fallback(new_smc); new_smc->fallback_rsn = reason_code; if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) { if (smc_clc_send_decline(new_smc, reason_code) < 0) { @@ -1223,7 +1241,7 @@ static void smc_listen_work(struct work_struct *work) /* check if peer is smc capable */ if (!tcp_sk(newclcsock->sk)->syn_smc) { - new_smc->use_fallback = true; + smc_switch_to_fallback(new_smc); new_smc->fallback_rsn = SMC_CLC_DECL_PEERNOSMC; smc_listen_out_connected(new_smc); return; @@ -1475,7 +1493,7 @@ static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) if (msg->msg_flags & MSG_FASTOPEN) { if (sk->sk_state == SMC_INIT) { - smc->use_fallback = true; + smc_switch_to_fallback(smc); smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP; } else { rc = -EINVAL; @@ -1672,7 +1690,7 @@ static int smc_setsockopt(struct socket *sock, int level, int optname, case TCP_FASTOPEN_NO_COOKIE: /* option not supported by SMC */ if (sk->sk_state == SMC_INIT) { - smc->use_fallback = true; + smc_switch_to_fallback(smc); smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP; } else { if (!smc->use_fallback) -- 2.34.1