net sysctl: Register an empty /proc/sys/net
Implementation limitations of the sysctl core won't let /proc/sys/net
reside in a network namespace. /proc/sys/net at least must be registered
as a normal sysctl. So register /proc/sys/net early as an empty directory
to guarantee we don't violate this constraint and hit bugs in the sysctl
implementation.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sysctl_net.c b/net/sysctl_net.c
index 3865c4f..2b2986d 100644
--- a/net/sysctl_net.c
+++ b/net/sysctl_net.c
@@ -88,9 +88,18 @@
.exit = sysctl_net_exit,
};
+static struct ctl_table_header *net_header;
static __init int net_sysctl_init(void)
{
- int ret;
+ static struct ctl_table empty[1];
+ int ret = -ENOMEM;
+ /* Avoid limitations in the sysctl implementation by
+ * registering "/proc/sys/net" as an empty directory not in a
+ * network namespace.
+ */
+ net_header = register_sysctl("net", empty);
+ if (!net_header)
+ goto out;
ret = register_pernet_subsys(&sysctl_pernet_ops);
if (ret)
goto out;