kevin/linux
1
Fork 0
Code

net/smc: Don't call clcsock shutdown twice when smc shutdown

Browse Source 
When applications call shutdown() with SHUT_RDWR in userspace,
smc_close_active() calls kernel_sock_shutdown(), and it is called
twice in smc_shutdown().

This fixes this by checking sk_state before do clcsock shutdown, and
avoids missing the application's call of smc_shutdown().

Link: https://lore.kernel.org/linux-s390/1f67548e-cbf6-0dce-82b5-10288a4583bd@linux.ibm.com/
Fixes: 606a63c978 ("net/smc: Ensure the active closing peer first closes clcsock")
Signed-off-by: Tony Lu <tonylu@linux.alibaba.com>
Reviewed-by: Wen Gu <guwen@linux.alibaba.com>
Acked-by: Karsten Graul <kgraul@linux.ibm.com>
Link: https://lore.kernel.org/r/20211126024134.45693-1-tonylu@linux.alibaba.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Tony Lu 2021-11-26 10:41:35 +08:00 committed by Jakub Kicinski
parent 01d9cc2dea
commit bacb6c1e47
1 changed files with 7 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
net/smc/af_smc.c
View File

@ -2370,8 +2370,10 @@ static __poll_t smc_poll(struct file *file, struct socket *sock,
static int smc_shutdown(struct socket *sock, int how)
{
struct sock *sk = sock->sk;
bool do_shutdown = true;
struct smc_sock *smc;
int rc = -EINVAL;
int old_state;
int rc1 = 0;
smc = smc_sk(sk);
@ -2398,7 +2400,11 @@ static int smc_shutdown(struct socket *sock, int how)
}
switch (how) {
case SHUT_RDWR: /* shutdown in both directions */
old_state = sk->sk_state;
rc = smc_close_active(smc);
if (old_state == SMC_ACTIVE &&
sk->sk_state == SMC_PEERCLOSEWAIT1)
do_shutdown = false;
break;
case SHUT_WR:
rc = smc_close_shutdown_write(smc);
@ -2408,7 +2414,7 @@ static int smc_shutdown(struct socket *sock, int how)
/* nothing more to do because peer is not involved */
break;
}
if (smc->clcsock)
if (do_shutdown && smc->clcsock)
rc1 = kernel_sock_shutdown(smc->clcsock, how);
/* map sock_shutdown_cmd constants to sk_shutdown value range */
sk->sk_shutdown |= how + 1;