From e1bbdd57047454dad068dc36612dd60a57f4c58f Mon Sep 17 00:00:00 2001 From: Ursula Braun Date: Thu, 5 Jul 2018 16:15:30 +0200 Subject: net/smc: reduce sock_put() for fallback sockets smc_release() calls a sock_put() for smc fallback sockets to cover the passive closing sock_hold() in __smc_connect() and smc_tcp_listen_work(). This does not make sense for sockets in state SMC_LISTEN and SMC_INIT. An SMC socket stays in state SMC_INIT if connect fails. The sock_put in smc_connect_abort() does not cover all failures. Move it into smc_connect_decline_fallback(). Fixes: ee9dfbef02d18 ("net/smc: handle sockopts forcing fallback") Reported-by: syzbot+3a0748c8f2f210c0ef9b@syzkaller.appspotmail.com Reported-by: syzbot+9e60d2428a42049a592a@syzkaller.appspotmail.com Signed-off-by: Ursula Braun Signed-off-by: David S. Miller --- net/smc/af_smc.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) (limited to 'net/smc/af_smc.c') diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index e017b6a4452b..5334157f5065 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -147,7 +147,8 @@ static int smc_release(struct socket *sock) smc->clcsock = NULL; } if (smc->use_fallback) { - sock_put(sk); /* passive closing */ + if (sk->sk_state != SMC_LISTEN && sk->sk_state != SMC_INIT) + sock_put(sk); /* passive closing */ sk->sk_state = SMC_CLOSED; sk->sk_state_change(sk); } @@ -417,12 +418,18 @@ static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code) { int rc; - if (reason_code < 0) /* error, fallback is not possible */ + if (reason_code < 0) { /* error, fallback is not possible */ + if (smc->sk.sk_state == SMC_INIT) + sock_put(&smc->sk); /* passive closing */ return reason_code; + } if (reason_code != SMC_CLC_DECL_REPLY) { rc = smc_clc_send_decline(smc, reason_code); - if (rc < 0) + if (rc < 0) { + if (smc->sk.sk_state == SMC_INIT) + sock_put(&smc->sk); /* passive closing */ return rc; + } } return smc_connect_fallback(smc); } @@ -435,8 +442,6 @@ static int smc_connect_abort(struct smc_sock *smc, int reason_code, smc_lgr_forget(smc->conn.lgr); mutex_unlock(&smc_create_lgr_pending); smc_conn_free(&smc->conn); - if (reason_code < 0 && smc->sk.sk_state == SMC_INIT) - sock_put(&smc->sk); /* passive closing */ return reason_code; } -- cgit v1.2.3 From 1992d99882afda6dc17f9d49c06150856a91282f Mon Sep 17 00:00:00 2001 From: Ursula Braun Date: Mon, 16 Jul 2018 13:56:52 +0200 Subject: net/smc: take sock lock in smc_ioctl() SMC ioctl processing requires the sock lock to work properly in all thinkable scenarios. Problem has been found with RaceFuzzer and fixes: KASAN: null-ptr-deref Read in smc_ioctl Reported-by: Byoungyoung Lee Reported-by: syzbot+35b2c5aa76fd398b9fd4@syzkaller.appspotmail.com Signed-off-by: Ursula Braun Reviewed-by: Stefano Brivio Signed-off-by: David S. Miller --- net/smc/af_smc.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) (limited to 'net/smc/af_smc.c') diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 5334157f5065..c12a7fc18f56 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -1524,10 +1524,13 @@ static int smc_ioctl(struct socket *sock, unsigned int cmd, return -EBADF; return smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg); } + lock_sock(&smc->sk); switch (cmd) { case SIOCINQ: /* same as FIONREAD */ - if (smc->sk.sk_state == SMC_LISTEN) + if (smc->sk.sk_state == SMC_LISTEN) { + release_sock(&smc->sk); return -EINVAL; + } if (smc->sk.sk_state == SMC_INIT || smc->sk.sk_state == SMC_CLOSED) answ = 0; @@ -1536,8 +1539,10 @@ static int smc_ioctl(struct socket *sock, unsigned int cmd, break; case SIOCOUTQ: /* output queue size (not send + not acked) */ - if (smc->sk.sk_state == SMC_LISTEN) + if (smc->sk.sk_state == SMC_LISTEN) { + release_sock(&smc->sk); return -EINVAL; + } if (smc->sk.sk_state == SMC_INIT || smc->sk.sk_state == SMC_CLOSED) answ = 0; @@ -1547,8 +1552,10 @@ static int smc_ioctl(struct socket *sock, unsigned int cmd, break; case SIOCOUTQNSD: /* output queue size (not send only) */ - if (smc->sk.sk_state == SMC_LISTEN) + if (smc->sk.sk_state == SMC_LISTEN) { + release_sock(&smc->sk); return -EINVAL; + } if (smc->sk.sk_state == SMC_INIT || smc->sk.sk_state == SMC_CLOSED) answ = 0; @@ -1556,8 +1563,10 @@ static int smc_ioctl(struct socket *sock, unsigned int cmd, answ = smc_tx_prepared_sends(&smc->conn); break; case SIOCATMARK: - if (smc->sk.sk_state == SMC_LISTEN) + if (smc->sk.sk_state == SMC_LISTEN) { + release_sock(&smc->sk); return -EINVAL; + } if (smc->sk.sk_state == SMC_INIT || smc->sk.sk_state == SMC_CLOSED) { answ = 0; @@ -1573,8 +1582,10 @@ static int smc_ioctl(struct socket *sock, unsigned int cmd, } break; default: + release_sock(&smc->sk); return -ENOIOCTLCMD; } + release_sock(&smc->sk); return put_user(answ, (int __user *)arg); } -- cgit v1.2.3 From ac0107edba253a6e58e923f9e68825decef3e681 Mon Sep 17 00:00:00 2001 From: Ursula Braun Date: Wed, 18 Jul 2018 15:22:50 +0200 Subject: net/smc: add error handling for get_user() For security reasons the return code of get_user() should always be checked. Fixes: 01d2f7e2cdd31 ("net/smc: sockopts TCP_NODELAY and TCP_CORK") Reported-by: Heiko Carstens Signed-off-by: Ursula Braun Signed-off-by: David S. Miller --- net/smc/af_smc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/smc/af_smc.c') diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index c12a7fc18f56..6e5479067db0 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -1456,7 +1456,8 @@ static int smc_setsockopt(struct socket *sock, int level, int optname, if (optlen < sizeof(int)) return -EINVAL; - get_user(val, (int __user *)optval); + if (get_user(val, (int __user *)optval)) + return -EFAULT; lock_sock(sk); switch (optname) { -- cgit v1.2.3