ipv6: fix rt6_update_expires
Commit 1716a961 (ipv6: fix problem with expired dst cache) broke PMTU
discovery. rt6_update_expires() calls dst_set_expires(), which only updates
dst->expires if it has not been set previously (expires == 0) or if the new
expires is earlier than the current dst->expires.
rt6_update_expires() needs to zero rt->dst.expires, otherwise it will contain
ivalid data left over from rt->dst.from and will confuse dst_set_expires().
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h
index c64778f..cb8da1d 100644
--- a/include/net/ip6_fib.h
+++ b/include/net/ip6_fib.h
@@ -143,8 +143,14 @@
static inline void rt6_update_expires(struct rt6_info *rt, int timeout)
{
- if (!(rt->rt6i_flags & RTF_EXPIRES) && rt->dst.from)
- dst_release(rt->dst.from);
+ if (!(rt->rt6i_flags & RTF_EXPIRES)) {
+ if (rt->dst.from)
+ dst_release(rt->dst.from);
+ /* dst_set_expires relies on expires == 0
+ * if it has not been set previously.
+ */
+ rt->dst.expires = 0;
+ }
dst_set_expires(&rt->dst, timeout);
rt->rt6i_flags |= RTF_EXPIRES;