[PATCH] net/smc: loop in smc_listen

Daxing Guo
2021-11-20T07:57:03Z

From: Guo DaXing <guodaxing@huawei.com>

The kernel_listen function in smc_listen will fail when all the available
ports are occupied. At this point smc->clcsock->sk->sk_data_ready has
been changed to smc_clcsock_data_ready. When we call smc_listen again,
now both smc->clcsock->sk->sk_data_ready and smc->clcsk_data_ready point
to the smc_clcsock_data_ready function.

The smc_clcsock_data_ready() function calls lsmc->clcsk_data_ready which
now points to itself resulting in an infinite loop.

This patch restores smc->clcsock->sk->sk_data_ready with the old value.

Signed-off-by: Guo DaXing <guodaxing@huawei.com>
---
net/smc/af_smc.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 59284da9116d..078f5edf6d4d 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -2120,8 +2120,10 @@ static int smc_listen(struct socket *sock, int backlog)
smc->clcsock->sk->sk_user_data =
(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
rc = kernel_listen(smc->clcsock, backlog);
- if (rc)
+ if (rc) {
+ smc->clcsock->sk->sk_data_ready = smc->clcsk_data_ready;
goto out;
+ }
sk->sk_max_ack_backlog = backlog;
sk->sk_ack_backlog = 0;
sk->sk_state = SMC_LISTEN;
--
2.20.1