ipv6 addrconf: disallow rtr_solicits < -1

This disallows setting /proc/sys/net/ipv6/conf/*/router_solicitations
to values below -1.

-1 continues to mean an unlimited number of retransmits.

Note: this depends on 'ipv6 addrconf: remove addrconf_sysctl_hop_limit()'

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index cbd9343..d8983e1 100644 (file)
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -5729,6 +5729,7 @@ int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
        return ret;
 }
 
+static int minus_one = -1;
 static const int one = 1;
 static const int two_five_five = 255;
 
@@ -5789,7 +5790,8 @@ static const struct ctl_table addrconf_sysctl[] = {
                .data           = &ipv6_devconf.rtr_solicits,
                .maxlen         = sizeof(int),
                .mode           = 0644,
-               .proc_handler   = proc_dointvec,
+               .proc_handler   = proc_dointvec_minmax,
+               .extra1         = &minus_one,
        },
        {
                .procname       = "router_solicitation_interval",