ipv6: Fix sysctl unregistration deadlock
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index f9afb45..40fabde 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -493,15 +493,17 @@
read_unlock(&dev_base_lock);
}
-static void addrconf_fixup_forwarding(struct ctl_table *table, int *p, int old)
+static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int old)
{
struct net *net;
net = (struct net *)table->extra2;
if (p == &net->ipv6.devconf_dflt->forwarding)
- return;
+ return 0;
- rtnl_lock();
+ if (!rtnl_trylock())
+ return -ERESTARTSYS;
+
if (p == &net->ipv6.devconf_all->forwarding) {
__s32 newf = net->ipv6.devconf_all->forwarding;
net->ipv6.devconf_dflt->forwarding = newf;
@@ -512,6 +514,7 @@
if (*p)
rt6_purge_dflt_routers(net);
+ return 1;
}
#endif
@@ -3983,7 +3986,7 @@
ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
if (write)
- addrconf_fixup_forwarding(ctl, valp, val);
+ ret = addrconf_fixup_forwarding(ctl, valp, val);
return ret;
}
@@ -4019,8 +4022,7 @@
}
*valp = new;
- addrconf_fixup_forwarding(table, valp, val);
- return 1;
+ return addrconf_fixup_forwarding(table, valp, val);
}
static struct addrconf_sysctl_table