Re: [PATCH net v3 1/1] net: tcp: Permit user set TCP_MAXSEG to default value

[David Miller]

From: f...@ikuai8.com
Date: Tue, 21 Mar 2017 09:28:03 +0800

> From: Gao Feng 
> 
> When user_mss is zero, it means use the default value. But the current
> codes don't permit user set TCP_MAXSEG to the default value.
> It would return the -EINVAL when val is zero.
> 
> Signed-off-by: Gao Feng 
> ---
>  v3: Correct the logic error, per Neal
>  v2: Make codes more clearer, per Eric
>  v1: initial version

Applied to net-next, thanks.

[PATCH net v3 1/1] net: tcp: Permit user set TCP_MAXSEG to default value

[fgao]

From: Gao Feng 

When user_mss is zero, it means use the default value. But the current
codes don't permit user set TCP_MAXSEG to the default value.
It would return the -EINVAL when val is zero.

Signed-off-by: Gao Feng 
---
 v3: Correct the logic error, per Neal
 v2: Make codes more clearer, per Eric
 v1: initial version

 net/ipv4/tcp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 1e319a5..4f7f163 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2470,7 +2470,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
/* Values greater than interface MTU won't take effect. However
 * at the point when this call is done we typically don't yet
 * know which interface is going to be used */
-   if (val < TCP_MIN_MSS || val > MAX_TCP_WINDOW) {
+   if (val && (val < TCP_MIN_MSS || val > MAX_TCP_WINDOW)) {
err = -EINVAL;
break;
}
-- 
1.9.1