net-tcp: /proc/sys/net/ipv4/tcp_probe_interval is a u32 not int
(fix documentation and sysctl access to treat it as such)
Tested:
# zcat /proc/config.gz | egrep ^CONFIG_HZ
CONFIG_HZ_1000=y
CONFIG_HZ=1000
# echo $[(1<<32)/1000 + 1] | tee /proc/sys/net/ipv4/tcp_probe_interval
4294968
tee: /proc/sys/net/ipv4/tcp_probe_interval: Invalid argument
# echo $[(1<<32)/1000] | tee /proc/sys/net/ipv4/tcp_probe_interval
4294967
# echo 0 | tee /proc/sys/net/ipv4/tcp_probe_interval
# echo -1 | tee /proc/sys/net/ipv4/tcp_probe_interval
-1
tee: /proc/sys/net/ipv4/tcp_probe_interval: Invalid argument
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index 8313a63..960de8f 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -425,7 +425,7 @@
1 - Disabled by default, enabled when an ICMP black hole detected
2 - Always enabled, use initial MSS of tcp_base_mss.
-tcp_probe_interval - INTEGER
+tcp_probe_interval - UNSIGNED INTEGER
Controls how often to start TCP Packetization-Layer Path MTU
Discovery reprobe. The default is reprobing every 10 minutes as
per RFC4821.
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index b92f422..891ed2f 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -48,6 +48,7 @@ static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
static int ip_ping_group_range_min[] = { 0, 0 };
static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
static int comp_sack_nr_max = 255;
+static u32 u32_max_div_HZ = UINT_MAX / HZ;
/* obsolete */
static int sysctl_tcp_low_latency __read_mostly;
@@ -745,9 +746,10 @@ static struct ctl_table ipv4_net_table[] = {
{
.procname = "tcp_probe_interval",
.data = &init_net.ipv4.sysctl_tcp_probe_interval,
- .maxlen = sizeof(int),
+ .maxlen = sizeof(u32),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = proc_douintvec_minmax,
+ .extra2 = &u32_max_div_HZ,
},
{
.procname = "igmp_link_local_mcast_reports",
