This fixes a regression in the bridge ageing time caused by:
commit c62987bbd8a1 ("bridge: push bridge setting ageing_time down to switchdev")
There are users of Linux bridge which use the feature that if ageing time
is set to 0 it causes entries to never expire.
This feature is even listed on the web page:
https://www.linuxfoundation.org/collaborate/workgroups/networking/bridge
For a pure software bridge, it is unnecessary for the code to have
arbitrary restrictions on what values are allowable.
Signed-off-by: Stephen Hemminger <stephen@xxxxxxxxxxxxxxxxxx>
---
Please apply to 4.4 for stable as well.
include/linux/if_bridge.h | 5 -----
net/bridge/br_stp.c | 9 ++++++---
2 files changed, 6 insertions(+), 8 deletions(-)
--- a/include/linux/if_bridge.h 2015-09-23 16:17:25.387594110 -0700
+++ b/include/linux/if_bridge.h 2016-02-11 07:49:35.016689397 -0800
@@ -45,11 +45,6 @@ struct br_ip_list {
#define BR_PROXYARP BIT(8)
#define BR_LEARNING_SYNC BIT(9)
#define BR_PROXYARP_WIFI BIT(10)
-
-/* values as per ieee8021QBridgeFdbAgingTime */
-#define BR_MIN_AGEING_TIME (10 * HZ)
-#define BR_MAX_AGEING_TIME (1000000 * HZ)
-
#define BR_DEFAULT_AGEING_TIME (300 * HZ)
extern void brioctl_set(int (*ioctl_hook)(struct net *, unsigned int, void __user *));
--- a/net/bridge/br_stp.c 2015-12-17 17:17:18.650746679 -0800
+++ b/net/bridge/br_stp.c 2016-02-11 07:49:53.240772672 -0800
@@ -568,6 +568,12 @@ int br_set_max_age(struct net_bridge *br
}
+/* Set the how long dynamic forwarding database entries live.
+ * The Linux bridge allows values outside the standard 802.1
+ * specification to allow for special cases:
+ * 0 - means entry never age.
+ * 1 - means entries disappear in next clock tick
+ */
int br_set_ageing_time(struct net_bridge *br, u32 ageing_time)
{
struct switchdev_attr attr = {
@@ -579,9 +585,6 @@ int br_set_ageing_time(struct net_bridge
unsigned long t = clock_t_to_jiffies(ageing_time);
int err;
- if (t < BR_MIN_AGEING_TIME || t > BR_MAX_AGEING_TIME)
- return -ERANGE;
-
err = switchdev_port_attr_set(br->dev, &attr);
if (err)
return err;
