diff options
author | Joe Stringer <joe@wand.net.nz> | 2020-03-30 01:53:39 +0300 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2020-03-30 23:45:04 +0300 |
commit | 71489e21d720a09388b565d60ef87ae993c10528 (patch) | |
tree | 0ebc9f8445150e0cf11c71c628ba69f7ae50da15 /net | |
parent | cf7fbe660f2dbd738ab58aea8e9b0ca6ad232449 (diff) | |
download | linux-71489e21d720a09388b565d60ef87ae993c10528.tar.xz |
net: Track socket refcounts in skb_steal_sock()
Refactor the UDP/TCP handlers slightly to allow skb_steal_sock() to make
the determination of whether the socket is reference counted in the case
where it is prefetched by earlier logic such as early_demux.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200329225342.16317-3-joe@wand.net.nz
Diffstat (limited to 'net')
-rw-r--r-- | net/ipv4/udp.c | 6 | ||||
-rw-r--r-- | net/ipv6/udp.c | 9 |
2 files changed, 10 insertions, 5 deletions
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 2633fc231593..b4035021bbd3 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -2288,6 +2288,7 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, struct rtable *rt = skb_rtable(skb); __be32 saddr, daddr; struct net *net = dev_net(skb->dev); + bool refcounted; /* * Validate the packet. @@ -2313,7 +2314,7 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, if (udp4_csum_init(skb, uh, proto)) goto csum_error; - sk = skb_steal_sock(skb); + sk = skb_steal_sock(skb, &refcounted); if (sk) { struct dst_entry *dst = skb_dst(skb); int ret; @@ -2322,7 +2323,8 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, udp_sk_rx_dst_set(sk, dst); ret = udp_unicast_rcv_skb(sk, skb, uh); - sock_put(sk); + if (refcounted) + sock_put(sk); return ret; } diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 5dc439a391fe..7d4151747340 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -843,6 +843,7 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, struct net *net = dev_net(skb->dev); struct udphdr *uh; struct sock *sk; + bool refcounted; u32 ulen = 0; if (!pskb_may_pull(skb, sizeof(struct udphdr))) @@ -879,7 +880,7 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, goto csum_error; /* Check if the socket is already available, e.g. due to early demux */ - sk = skb_steal_sock(skb); + sk = skb_steal_sock(skb, &refcounted); if (sk) { struct dst_entry *dst = skb_dst(skb); int ret; @@ -888,12 +889,14 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, udp6_sk_rx_dst_set(sk, dst); if (!uh->check && !udp_sk(sk)->no_check6_rx) { - sock_put(sk); + if (refcounted) + sock_put(sk); goto report_csum_error; } ret = udp6_unicast_rcv_skb(sk, skb, uh); - sock_put(sk); + if (refcounted) + sock_put(sk); return ret; } |