From 67f562e3e147750a02b2a91d21a163fc44a1d13e Mon Sep 17 00:00:00 2001 From: Ursula Braun Date: Fri, 14 Feb 2020 08:58:59 +0100 Subject: [PATCH] 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: ee9dfbef02d18 ("net/smc: handle sockopts forcing fallback") Signed-off-by: Ursula Braun Signed-off-by: Karsten Graul Signed-off-by: David S. Miller --- net/smc/af_smc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index cee5bf4a9bb9..90988a511cd5 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -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; } }