[PATCH net] net/smc: do not schedule tx_work in SMC_CLOSED state

[Karsten Graul]

From: Ursula Braun <ubr...@linux.ibm.com>

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+92209502e7aab127c...@syzkaller.appspotmail.com
Reported-by: syzbot+b972214bb803a343f...@syzkaller.appspotmail.com
Fixes: 01d2f7e2cdd31 ("net/smc: sockopts TCP_NODELAY and TCP_CORK")
Signed-off-by: Ursula Braun <ubr...@linux.ibm.com>
Signed-off-by: Karsten Graul <kgr...@linux.ibm.com>
---
 net/smc/af_smc.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 302e355f2ebc..f5ea09258ab0 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -1732,14 +1732,18 @@ 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);
-- 
2.21.0