ipv4: Fix rp_filter description in net/ipv4/Kconfig.

The reverse path filter (rp_filter) will NOT get enabled
when enabling forwarding.  Read the code and tested in
in practice.

Most distributions do enable it in startup scripts.

Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
index 691268f..10c944d 100644 (file)
--- a/net/ipv4/Kconfig
+++ b/net/ipv4/Kconfig
@@ -35,7 +35,7 @@ config IP_ADVANCED_ROUTER
 
          at boot time after the /proc file system has been mounted.
 
-         If you turn on IP forwarding, you will also get the rp_filter, which
+         If you turn on IP forwarding, you should consider the rp_filter, which
          automatically rejects incoming packets if the routing table entry
          for their source address doesn't match the network interface they're
          arriving on. This has security advantages because it prevents the
@@ -46,9 +46,11 @@ config IP_ADVANCED_ROUTER
          rp_filter on use:
 
          echo 1 > /proc/sys/net/ipv4/conf/<device>/rp_filter
-         or
+          and
          echo 1 > /proc/sys/net/ipv4/conf/all/rp_filter
 
+         Note that some distributions enable it in startup scripts.
+
          If unsure, say N here.
 
 choice