4.17-stable review patch. If anyone has any objections, please let me know.
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From: Ursula Braun ubraun@linux.ibm.com
commit caa21e19e08d7a1445116a93f7ab4e187ebbbadb upstream.
Invoking shutdown for a socket in state SMC_LISTEN does not make sense. Nevertheless programs like syzbot fuzzing the kernel may try to do this. For SMC this means a socket refcounting problem. This patch makes sure a shutdown call for an SMC socket in state SMC_LISTEN simply returns with -ENOTCONN.
Signed-off-by: Ursula Braun ubraun@linux.ibm.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/smc/af_smc.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
--- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -1231,8 +1231,7 @@ static int smc_shutdown(struct socket *s lock_sock(sk);
rc = -ENOTCONN; - if ((sk->sk_state != SMC_LISTEN) && - (sk->sk_state != SMC_ACTIVE) && + if ((sk->sk_state != SMC_ACTIVE) && (sk->sk_state != SMC_PEERCLOSEWAIT1) && (sk->sk_state != SMC_PEERCLOSEWAIT2) && (sk->sk_state != SMC_APPCLOSEWAIT1) &&