diff options
| author | Steffen Klassert <steffen.klassert@secunet.com> | 2013-01-22 00:01:28 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-02-14 10:48:32 -0800 |
| commit | 4ad45ec2e4660a7643a0434b1db47085532afdb1 (patch) | |
| tree | c5b28f7b5d4db4d14341cefb4e38cadee1156e71 /net | |
| parent | 5874dd2fa88cc8b977b839a70679d61624e89ad4 (diff) | |
ipv4: Fix route refcount on pmtu discovery
[ Upstream commit b44108dbdbaa07c609bb5755e8dd6c2035236251 ]
git commit 9cb3a50c (ipv4: Invalidate the socket cached route on
pmtu events if possible) introduced a refcount problem. We don't
get a refcount on the route if we get it from__sk_dst_get(), but
we need one if we want to reuse this route because __sk_dst_set()
releases the refcount of the old route. This patch adds proper
refcount handling for that case. We introduce a 'new' flag to
indicate that we are going to use a new route and we release the
old route only if we replace it by a new one.
Reported-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/route.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/net/ipv4/route.c b/net/ipv4/route.c index fc6a6b46c59d..0fdfe4c571cd 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -985,6 +985,7 @@ void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu) struct flowi4 fl4; struct rtable *rt; struct dst_entry *dst; + bool new = false; bh_lock_sock(sk); rt = (struct rtable *) __sk_dst_get(sk); @@ -1000,20 +1001,26 @@ void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu) rt = ip_route_output_flow(sock_net(sk), &fl4, sk); if (IS_ERR(rt)) goto out; + + new = true; } __ip_rt_update_pmtu((struct rtable *) rt->dst.path, &fl4, mtu); dst = dst_check(&rt->dst, 0); if (!dst) { + if (new) + dst_release(&rt->dst); + rt = ip_route_output_flow(sock_net(sk), &fl4, sk); if (IS_ERR(rt)) goto out; - dst = &rt->dst; + new = true; } - __sk_dst_set(sk, dst); + if (new) + __sk_dst_set(sk, &rt->dst); out: bh_unlock_sock(sk); |