net/smc: do not schedule tx_work in SMC_CLOSED state

[ Upstream commit f9cedf1a9b1cdcfb0c52edb391d01771e43994a4 ]

The setsockopts options TCP_NODELAY and TCP_CORK may schedule the
tx worker. Make sure the socket is not yet moved into SMC_CLOSED
state (for instance by a shutdown SHUT_RDWR call).

Reported-by: syzbot+92209502e7aab127c75f@syzkaller.appspotmail.com
Reported-by: syzbot+b972214bb803a343f4fe@syzkaller.appspotmail.com
Fixes: 01d2f7e2cdd31 ("net/smc: sockopts TCP_NODELAY and TCP_CORK")
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 9bbab6ba2dab0d9c2d685453371233576ba7e1a9..26dcd02b2d0cefbd2874edb1132f2e0d64dab97c 100644 (file)
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -1680,14 +1680,18 @@ static int smc_setsockopt(struct socket *sock, int level, int optname,
                }
                break;
        case TCP_NODELAY:
-               if (sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) {
+               if (sk->sk_state != SMC_INIT &&
+                   sk->sk_state != SMC_LISTEN &&
+                   sk->sk_state != SMC_CLOSED) {
                        if (val && !smc->use_fallback)
                                mod_delayed_work(system_wq, &smc->conn.tx_work,
                                                 0);
                }
                break;
        case TCP_CORK:
-               if (sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) {
+               if (sk->sk_state != SMC_INIT &&
+                   sk->sk_state != SMC_LISTEN &&
+                   sk->sk_state != SMC_CLOSED) {
                        if (!val && !smc->use_fallback)
                                mod_delayed_work(system_wq, &smc->conn.tx_work,
                                                 0);