On Tue, Aug 08, 2023 at 01:20:36PM +0200, Przemek Kitszel wrote:

On 7/31/23 09:17, Joel Granados wrote:

quoted

Move from register_net_sysctl to register_net_sysctl_sz for all the
networking related files. Do this while making sure to mirror the NULL
assignments with a table_size of zero for the unprivileged users.

We need to move to the new function in preparation for when we change
SIZE_MAX to ARRAY_SIZE() in the register_net_sysctl macro. Failing to do
so would erroneously allow ARRAY_SIZE() to be called on a pointer. We
hold off the SIZE_MAX to ARRAY_SIZE change until we have migrated all
the relevant net sysctl registering functions to register_net_sysctl_sz
in subsequent commits.

An additional size function was added to the following files in order to
calculate the size of an array that is defined in another file:
     include/net/ipv6.h
     net/ipv6/icmp.c
     net/ipv6/route.c

...

quoted

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 64e873f5895f..51c6cdae8723 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c

@@ -6447,14 +6447,19 @@ struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
  		table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
  		table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
  		table[10].data = &net->ipv6.sysctl.skip_notify_on_dev_down;
-
-		/* Don't export sysctls to unprivileged users */
-		if (net->user_ns != &init_user_ns)
-			table[1].procname = NULL;

Here I remove the setting of the procname to NULL for ipv6 sysctl
registers in route.c and I do not replace that assignment anywhere.
This means that we will export sysctls to unprivilged users for ipv6.
I'll correct this in V3.

quoted

  	}
  	return table;
  }
+
+size_t ipv6_route_sysctl_table_size(struct net *net)
+{
+	/* Don't export sysctls to unprivileged users */
+	if (net->user_ns != &init_user_ns)
+		return 0;
+
+	return ARRAY_SIZE(ipv6_route_table_template);
+}
  #endif
  static int __net_init ip6_route_net_init(struct net *net)

-- 

Joel Granados