net/smc: transfer fasync_list in case of fallback

SMC does not work together with FASTOPEN. If sendmsg() is called with
flag MSG_FASTOPEN in SMC_INIT state, the SMC-socket switches to
fallback mode. To handle the previous ioctl FIOASYNC call correctly
in this case, it is necessary to transfer the socket wait queue
fasync_list to the internal TCP socket.

Reported-by: syzbot+4b1fe8105f8044a26162@syzkaller.appspotmail.com
Fixes: ee9dfbef02 ("net/smc: handle sockopts forcing fallback")
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>
This commit is contained in:
Ursula Braun 2020-02-14 08:58:59 +01:00 committed by David S. Miller
parent dc221a28d0
commit 67f562e3e1

View File

@ -470,6 +470,8 @@ static void smc_switch_to_fallback(struct smc_sock *smc)
if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
smc->clcsock->file = smc->sk.sk_socket->file;
smc->clcsock->file->private_data = smc->clcsock;
smc->clcsock->wq.fasync_list =
smc->sk.sk_socket->wq.fasync_list;
}
}