net: ipv{6,4}: Remove the now superfluous sentinel elements from ctl_table array

This commit comes at the tail end of a greater effort to remove the
empty elements at the end of the ctl_table arrays (sentinels) which
will reduce the overall build time size of the kernel and run time
memory bloat by ~64 bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)

* Remove sentinel element from ctl_table structs.
* Remove the zeroing out of an array element (to make it look like a
  sentinel) in sysctl_route_net_init And ipv6_route_sysctl_init.
  This is not longer needed and is safe after commit c899710fe7f9
  ("networking: Update to register_net_sysctl_sz") added the array size
  to the ctl_table registration.
* Remove extra sentinel element in the declaration of devinet_vars.
* Removed the "-1" in __devinet_sysctl_register, sysctl_route_net_init,
  ipv6_sysctl_net_init and ipv4_sysctl_init_net that adjusted for having
  an extra empty element when looping over ctl_table arrays
* Replace the for loop stop condition in __addrconf_sysctl_register that
  tests for procname == NULL with one that depends on array size
* Removing the unprivileged user check in ipv6_route_sysctl_init is
  safe as it is replaced by calling ipv6_route_sysctl_table_size;
  introduced in commit c899710fe7f9 ("networking: Update to
  register_net_sysctl_sz")
* Use a table_size variable to keep the value of ARRAY_SIZE

Signed-off-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 6 deletions

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 0fd9a3d7ac4a..5fd54103174f 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -3496,7 +3496,6 @@ static struct ctl_table ipv4_route_table[] = {
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec,
 	},
-	{ }
 };
 
 static const char ipv4_route_flush_procname[] = "flush";
@@ -3530,7 +3529,6 @@ static struct ctl_table ipv4_route_netns_table[] = {
 		.mode       = 0644,
 		.proc_handler   = proc_dointvec,
 	},
-	{ },
 };
 
 static __net_init int sysctl_route_net_init(struct net *net)
@@ -3548,16 +3546,14 @@ static __net_init int sysctl_route_net_init(struct net *net)
 
 		/* Don't export non-whitelisted sysctls to unprivileged users */
 		if (net->user_ns != &init_user_ns) {
-			if (tbl[0].procname != ipv4_route_flush_procname) {
-				tbl[0].procname = NULL;
+			if (tbl[0].procname != ipv4_route_flush_procname)
 				table_size = 0;
-			}
 		}
 
 		/* Update the variables to point into the current struct net
 		 * except for the first element flush
 		 */
-		for (i = 1; i < ARRAY_SIZE(ipv4_route_netns_table) - 1; i++)
+		for (i = 1; i < table_size; i++)
 			tbl[i].data += (void *)net - (void *)&init_net;
 	}
 	tbl[0].extra1 = net;