net: fix regression introduced in 2.6.32.62 by sysctl fixes

Commits b7c9e4ee ("sysctl net: Keep tcp_syn_retries inside the boundary")
and eedcafdc ("net: check net.core.somaxconn sysctl values") were missing
a .strategy entry which is still required in 2.6.32. Because of this, the
Ubuntu kernel team has faced kernel dumps during their testing.

Tyler Hicks and Luis Henriques proposed this patch to fix the issue,
which properly sets .strategy as needed in 2.6.32.
Reported-by: Luis Henriques <luis.henriques@canonical.com>
Cc: tyler.hicks@canonical.com
Cc: Michal Tesar <mtesar@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>

net/core/sysctl_net_core.c

@@ -121,7 +121,8 @@ static struct ctl_table netns_core_table[] = {
 		.mode		= 0644,
 		.extra1		= &zero,
 		.extra2		= &ushort_max,
-		.proc_handler	= proc_dointvec_minmax
+		.proc_handler	= proc_dointvec_minmax,
+		.strategy	= &sysctl_intvec
 	},
 	{ .ctl_name = 0 }
 };

net/ipv4/sysctl_net_ipv4.c

@@ -241,7 +241,8 @@ static struct ctl_table ipv4_table[] = {
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec_minmax,
 		.extra1		= &tcp_syn_retries_min,
-		.extra2		= &tcp_syn_retries_max
+		.extra2		= &tcp_syn_retries_max,
+		.strategy	= &sysctl_intvec
 	},
 	{
 		.ctl_name	= NET_IPV4_NONLOCAL_BIND,