ipv4: remove static flush_delay variable (639e104f) · Commits · 戴 / test

flush delay is used as an external storage for net.ipv4.route.flush sysctl entry. It is write-only. The ctl_table->data for this entry is used once. Fix this case to point to the stack to remove global variable. Do this to avoid additional variable on struct net in the next patch. Possible race (as it was before) accessing this local variable is removed using flush_mutex. Signed-off-by:

Denis V. Lunev <den@openvz.org> Signed-off-by:

David S. Miller <davem@davemloft.net>

net/ipv4/route.c

+8 −3

Original line number	Diff line number	Diff line
		@@ -2829,14 +2829,20 @@ void ip_rt_multicast_event(struct in_device *in_dev)
		}

		#ifdef CONFIG_SYSCTL
		static int flush_delay;

		static int ipv4_sysctl_rtcache_flush(ctl_table *ctl, int write,
		struct file filp, void __user buffer,
		size_t lenp, loff_t ppos)
		{
		if (write) {
		int flush_delay;
		static DEFINE_MUTEX(flush_mutex);

		mutex_lock(&flush_mutex);
		ctl->data = &flush_delay;
		proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
		ctl->data = NULL;
		mutex_unlock(&flush_mutex);

		rt_cache_flush(&init_net, flush_delay);
		return 0;
		}
		@@ -2865,7 +2871,6 @@ ctl_table ipv4_route_table[] = {
		{
		.ctl_name = NET_IPV4_ROUTE_FLUSH,
		.procname = "flush",
		.data = &flush_delay,
		.maxlen = sizeof(int),
		.mode = 0200,
		.proc_handler = &ipv4_sysctl_rtcache_flush,

Admin message