tcp: restrict net.ipv4.tcp_adv_win_scale (#20312)

[cascardo/linux.git] / net / ipv4 / sysctl_net_ipv4.c

diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index e91911d..1b4ec21 100644 (file)
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -26,6 +26,8 @@ static int zero;
 static int tcp_retr1_max = 255;
 static int ip_local_port_range_min[] = { 1, 1 };
 static int ip_local_port_range_max[] = { 65535, 65535 };
+static int tcp_adv_win_scale_min = -31;
+static int tcp_adv_win_scale_max = 31;
 
 /* Update system visible IP port range */
 static void set_local_port_range(int range[2])
@@ -426,7 +428,9 @@ static struct ctl_table ipv4_table[] = {
                .data           = &sysctl_tcp_adv_win_scale,
                .maxlen         = sizeof(int),
                .mode           = 0644,
-               .proc_handler   = proc_dointvec
+               .proc_handler   = proc_dointvec_minmax,
+               .extra1         = &tcp_adv_win_scale_min,
+               .extra2         = &tcp_adv_win_scale_max,
        },
        {
                .procname       = "tcp_tw_reuse",