diff options
| author | Ursula Braun <ubraun@linux.ibm.com> | 2018-05-02 16:53:56 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-05-02 13:27:19 -0400 |
| commit | 784813aed6ba24a1f24e7e11d9d0f208cee37a7d (patch) | |
| tree | dbcd307055b4f0361d8b426306746b0aa09181ea | |
| parent | af3e0fcf78879f718c5f73df0814951bd7057d34 (diff) | |
| download | linux-784813aed6ba24a1f24e7e11d9d0f208cee37a7d.tar.bz2 | |
net/smc: restrict non-blocking connect finish
The smc_poll code tries to finish connect() if the socket is in
state SMC_INIT and polling of the internal CLC-socket returns with
EPOLLOUT. This makes sense for a select/poll call following a connect
call, but not without preceding connect().
With this patch smc_poll starts connect logic only, if the CLC-socket
is no longer in its initial state TCP_CLOSE.
In addition, a poll error on the internal CLC-socket is always
propagated to the SMC socket.
With this patch the code path mentioned by syzbot
https://syzkaller.appspot.com/bug?extid=03faa2dc16b8b64be396
is no longer possible.
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Reported-by: syzbot+03faa2dc16b8b64be396@syzkaller.appspotmail.com
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/smc/af_smc.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 4470501374bf..8b4c059bd13b 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -1166,13 +1166,15 @@ static __poll_t smc_poll(struct file *file, struct socket *sock, /* delegate to CLC child sock */ release_sock(sk); mask = smc->clcsock->ops->poll(file, smc->clcsock, wait); - /* if non-blocking connect finished ... */ lock_sock(sk); - if ((sk->sk_state == SMC_INIT) && (mask & EPOLLOUT)) { - sk->sk_err = smc->clcsock->sk->sk_err; - if (sk->sk_err) { - mask |= EPOLLERR; - } else { + sk->sk_err = smc->clcsock->sk->sk_err; + if (sk->sk_err) { + mask |= EPOLLERR; + } else { + /* if non-blocking connect finished ... */ + if (sk->sk_state == SMC_INIT && + mask & EPOLLOUT && + smc->clcsock->sk->sk_state != TCP_CLOSE) { rc = smc_connect_rdma(smc); if (rc < 0) mask |= EPOLLERR; |