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| author |   Paolo Abeni <pabeni@redhat.com> | 2017-08-25 14:31:01 +0200 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-09-20 08:22:07 +0200 |
| commit | 38ca2d395e1cd24f205db3176c4ce9198f22576e (patch) | |
| tree | c921502a8678e231a1949fd751bd683a2024105b | |
| parent | netvsc: fix deadlock betwen link status and removal (diff) | |
| download | linux-stable-38ca2d395e1cd24f205db3176c4ce9198f22576e.tar.xz linux-stable-38ca2d395e1cd24f205db3176c4ce9198f22576e.zip | |
udp6: set rx_dst_cookie on rx_dst updates
[ Upstream commit 64f0f5d18a47c703c85576375cc010e83dac6a48 ]
Currently, in the udp6 code, the dst cookie is not initialized/updated
concurrently with the RX dst used by early demux.
As a result, the dst_check() in the early_demux path always fails,
the rx dst cache is always invalidated, and we can't really
leverage significant gain from the demux lookup.
Fix it adding udp6 specific variant of sk_rx_dst_set() and use it
to set the dst cookie when the dst entry is really changed.
The issue is there since the introduction of early demux for ipv6.
Fixes: 5425077d73e0 ("net: ipv6: Add early demux handler for UDP unicast")
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | include/net/udp.h | 2 | ||||
| -rw-r--r-- | net/ipv4/udp.c | 3 | ||||
| -rw-r--r-- | net/ipv6/udp.c | 11 |
3 files changed, 13 insertions, 3 deletions
diff --git a/include/net/udp.h b/include/net/udp.h index 1933442cf1a6..a1bc3e7934d6 100644 --- a/include/net/udp.h +++ b/include/net/udp.h @@ -265,7 +265,7 @@ static inline struct sk_buff *skb_recv_udp(struct sock *sk, unsigned int flags, } void udp_v4_early_demux(struct sk_buff *skb); -void udp_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst); +bool udp_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst); int udp_get_port(struct sock *sk, unsigned short snum, int (*saddr_cmp)(const struct sock *, const struct sock *)); diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index c991b97cbb28..2a7bff749764 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1762,13 +1762,14 @@ drop: /* For TCP sockets, sk_rx_dst is protected by socket lock * For UDP, we use xchg() to guard against concurrent changes. */ -void udp_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst) +bool udp_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst) { struct dst_entry *old; dst_hold(dst); old = xchg(&sk->sk_rx_dst, dst); dst_release(old); + return old != dst; } /* diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 592270c310f4..5c7b2a94e358 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -752,6 +752,15 @@ start_lookup: return 0; } +static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst) +{ + if (udp_sk_rx_dst_set(sk, dst)) { + const struct rt6_info *rt = (const struct rt6_info *)dst; + + inet6_sk(sk)->rx_dst_cookie = rt6_get_cookie(rt); + } +} + int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, int proto) { @@ -801,7 +810,7 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, int ret; if (unlikely(sk->sk_rx_dst != dst)) - udp_sk_rx_dst_set(sk, dst); + udp6_sk_rx_dst_set(sk, dst); ret = udpv6_queue_rcv_skb(sk, skb); sock_put(sk); |