From: D. Wythe alibuda@linux.alibaba.com
[ Upstream commit ce7ca794712f186da99719e8b4e97bd5ddbb04c3 ]
Before determining whether the msg has unsupported options, it has been prematurely terminated by the wrong status check.
For the application, the general usages of MSG_FASTOPEN likes
fd = socket(...) /* rather than connect */ sendto(fd, data, len, MSG_FASTOPEN)
Hence, We need to check the flag before state check, because the sock state here is always SMC_INIT when applications tries MSG_FASTOPEN. Once we found unsupported options, fallback it to TCP.
Fixes: ee9dfbef02d1 ("net/smc: handle sockopts forcing fallback") Signed-off-by: D. Wythe alibuda@linux.alibaba.com Signed-off-by: Simon Horman simon.horman@corigine.com
v2 -> v1: Optimize code style Reviewed-by: Tony Lu tonylu@linux.alibaba.com
Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/smc/af_smc.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 5d696b7fb47e1..b398d72a7bc39 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -1542,16 +1542,14 @@ static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) { struct sock *sk = sock->sk; struct smc_sock *smc; - int rc = -EPIPE; + int rc;
smc = smc_sk(sk); lock_sock(sk); - if ((sk->sk_state != SMC_ACTIVE) && - (sk->sk_state != SMC_APPCLOSEWAIT1) && - (sk->sk_state != SMC_INIT)) - goto out;
+ /* SMC does not support connect with fastopen */ if (msg->msg_flags & MSG_FASTOPEN) { + /* not connected yet, fallback */ if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) { smc_switch_to_fallback(smc); smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP; @@ -1559,6 +1557,11 @@ static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) rc = -EINVAL; goto out; } + } else if ((sk->sk_state != SMC_ACTIVE) && + (sk->sk_state != SMC_APPCLOSEWAIT1) && + (sk->sk_state != SMC_INIT)) { + rc = -EPIPE; + goto out; }
if (smc->use_fallback)