diff mbox

[net-next] avoid to hang up on sending since sysctl configuration overflow.

Message ID 1359009328-24582-1-git-send-email-bingtian.ly@taobao.com
State Accepted, archived
Delegated to: David Miller
Headers show

Commit Message

Li Yu Jan. 24, 2013, 6:35 a.m. UTC 
From: bingtian.ly@taobao.com

    I found if we write large than 4GB value to some sysctl variables,
the sending syscall will hang up forever, because of these variables
are 32 bits, such large value bring them overflow to 0 or negative.

    This patch try to fix overflow or prevent from zero value setup
of below sysctl variables:

net.core.wmem_default
net.core.rmem_default

net.core.rmem_max
net.core.wmem_max

net.ipv4.udp_rmem_min
net.ipv4.udp_wmem_min

net.ipv4.tcp_wmem
net.ipv4.tcp_rmem

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Li Yu <raise.sail@gmail.com>
---
 core/sysctl_net_core.c |   14 ++++++++++----
 ipv4/sysctl_net_ipv4.c |   11 +++++++----
 2 files changed, 17 insertions(+), 8 deletions(-)

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Comments

David Miller Jan. 29, 2013, 4:16 a.m. UTC | #1 
From: Li Yu <raise.sail@gmail.com>
Date: Thu, 24 Jan 2013 14:35:28 +0800

> From: bingtian.ly@taobao.com
> 
>     I found if we write large than 4GB value to some sysctl variables,
> the sending syscall will hang up forever, because of these variables
> are 32 bits, such large value bring them overflow to 0 or negative.
> 
>     This patch try to fix overflow or prevent from zero value setup
> of below sysctl variables:
> 
> net.core.wmem_default
> net.core.rmem_default
> 
> net.core.rmem_max
> net.core.wmem_max
> 
> net.ipv4.udp_rmem_min
> net.ipv4.udp_wmem_min
> 
> net.ipv4.tcp_wmem
> net.ipv4.tcp_rmem
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
> Signed-off-by: Li Yu <raise.sail@gmail.com>

Applied, thanks.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
index d1b0804..cfdb46a 100644
--- a/net/core/sysctl_net_core.c
+++ b/net/core/sysctl_net_core.c
@@ -20,6 +20,8 @@ 
 #include <net/sock.h>
 #include <net/net_ratelimit.h>
 
+static int one = 1;
+
 #ifdef CONFIG_RPS
 static int rps_sock_flow_sysctl(ctl_table *table, int write,
 				void __user *buffer, size_t *lenp, loff_t *ppos)
@@ -92,28 +94,32 @@  static struct ctl_table net_core_table[] = {
 		.data		= &sysctl_wmem_max,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &one,
 	},
 	{
 		.procname	= "rmem_max",
 		.data		= &sysctl_rmem_max,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &one,
 	},
 	{
 		.procname	= "wmem_default",
 		.data		= &sysctl_wmem_default,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &one,
 	},
 	{
 		.procname	= "rmem_default",
 		.data		= &sysctl_rmem_default,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &one,
 	},
 	{
 		.procname	= "dev_weight",
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index a25e1d2..2622707 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -27,6 +27,7 @@ 
 #include <net/tcp_memcontrol.h>
 
 static int zero;
+static int one = 1;
 static int two = 2;
 static int tcp_retr1_max = 255;
 static int ip_local_port_range_min[] = { 1, 1 };
@@ -549,14 +550,16 @@  static struct ctl_table ipv4_table[] = {
 		.data		= &sysctl_tcp_wmem,
 		.maxlen		= sizeof(sysctl_tcp_wmem),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &one,
 	},
 	{
 		.procname	= "tcp_rmem",
 		.data		= &sysctl_tcp_rmem,
 		.maxlen		= sizeof(sysctl_tcp_rmem),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &one,
 	},
 	{
 		.procname	= "tcp_app_win",
@@ -779,7 +782,7 @@  static struct ctl_table ipv4_table[] = {
 		.maxlen		= sizeof(sysctl_udp_rmem_min),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= &zero
+		.extra1		= &one
 	},
 	{
 		.procname	= "udp_wmem_min",
@@ -787,7 +790,7 @@  static struct ctl_table ipv4_table[] = {
 		.maxlen		= sizeof(sysctl_udp_wmem_min),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= &zero
+		.extra1		= &one
 	},
 	{ }
 };