net: avoid to hang up on sending due to sysctl configuration overflow.
commit cdda88912d62f9603d27433338a18be83ef23ac1 upstream.
I found if we write a larger than 4GB value to some sysctl
variables, the sending syscall will hang up forever, because these
variables are 32 bits, such large values make 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>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2:
- Adjust context
- Delete now-unused 'zero' variable]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
(cherry picked from commit 98eee187cdee2807bd80e6c02180c5c2abae6453)
[wt: backported to 2.6.32: set strategy to sysctl_intvec where relevant]
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
index e6bf72c..a600328 100644
--- a/net/core/sysctl_net_core.c
+++ b/net/core/sysctl_net_core.c
@@ -17,6 +17,8 @@
static int zero = 0;
static int ushort_max = 65535;
+static int one = 1;
+
static struct ctl_table net_core_table[] = {
#ifdef CONFIG_NET
{
@@ -25,7 +27,9 @@
.data = &sysctl_wmem_max,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec
+ .proc_handler = proc_dointvec_minmax,
+ .strategy = sysctl_intvec,
+ .extra1 = &one,
},
{
.ctl_name = NET_CORE_RMEM_MAX,
@@ -33,7 +37,9 @@
.data = &sysctl_rmem_max,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec
+ .proc_handler = proc_dointvec_minmax,
+ .strategy = sysctl_intvec,
+ .extra1 = &one,
},
{
.ctl_name = NET_CORE_WMEM_DEFAULT,
@@ -41,7 +47,9 @@
.data = &sysctl_wmem_default,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec
+ .proc_handler = proc_dointvec_minmax,
+ .strategy = sysctl_intvec,
+ .extra1 = &one,
},
{
.ctl_name = NET_CORE_RMEM_DEFAULT,
@@ -49,7 +57,9 @@
.data = &sysctl_rmem_default,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec
+ .proc_handler = proc_dointvec_minmax,
+ .strategy = sysctl_intvec,
+ .extra1 = &one,
},
{
.ctl_name = NET_CORE_DEV_WEIGHT,
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index d957371..d1a8883 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -22,6 +22,7 @@
#include <net/inet_frag.h>
static int zero;
+static int one = 1;
static int tcp_retr1_max = 255;
static int tcp_syn_retries_min = 1;
static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
@@ -521,7 +522,9 @@
.data = &sysctl_tcp_wmem,
.maxlen = sizeof(sysctl_tcp_wmem),
.mode = 0644,
- .proc_handler = proc_dointvec
+ .proc_handler = proc_dointvec_minmax,
+ .strategy = sysctl_intvec,
+ .extra1 = &one,
},
{
.ctl_name = NET_TCP_RMEM,
@@ -529,7 +532,9 @@
.data = &sysctl_tcp_rmem,
.maxlen = sizeof(sysctl_tcp_rmem),
.mode = 0644,
- .proc_handler = proc_dointvec
+ .proc_handler = proc_dointvec_minmax,
+ .strategy = sysctl_intvec,
+ .extra1 = &one,
},
{
.ctl_name = NET_TCP_APP_WIN,
@@ -735,7 +740,7 @@
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.strategy = sysctl_intvec,
- .extra1 = &zero
+ .extra1 = &one
},
{
.ctl_name = CTL_UNNUMBERED,
@@ -745,7 +750,7 @@
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.strategy = sysctl_intvec,
- .extra1 = &zero
+ .extra1 = &one
},
{ .ctl_name = 0 }
};
