From: Eric Dumazet edumazet@google.com
[ Upstream commit 6579f5bacc2c4cbc5ef6abb45352416939d1f844 ]
Some applications seem to rely on RAW sockets.
If they use private netns, we can avoid piling all RAW sockets bound to a given protocol into a single bucket.
Also place (struct raw_hashinfo).lock into its own cache line to limit false sharing.
Alternative would be to have per-netns hashtables, but this seems too expensive for most netns where RAW sockets are not used.
Signed-off-by: Eric Dumazet edumazet@google.com Signed-off-by: Jakub Kicinski kuba@kernel.org Stable-dep-of: 0a78cf7264d2 ("raw: Fix NULL deref in raw_get_next().") Signed-off-by: Sasha Levin sashal@kernel.org --- include/net/raw.h | 13 +++++++++++-- net/ipv4/raw.c | 13 +++++++------ net/ipv6/raw.c | 4 ++-- 3 files changed, 20 insertions(+), 10 deletions(-)
diff --git a/include/net/raw.h b/include/net/raw.h index 5e665934ebc7c..2c004c20ed996 100644 --- a/include/net/raw.h +++ b/include/net/raw.h @@ -15,6 +15,8 @@
#include <net/inet_sock.h> #include <net/protocol.h> +#include <net/netns/hash.h> +#include <linux/hash.h> #include <linux/icmp.h>
extern struct proto raw_prot; @@ -29,13 +31,20 @@ int raw_local_deliver(struct sk_buff *, int);
int raw_rcv(struct sock *, struct sk_buff *);
-#define RAW_HTABLE_SIZE MAX_INET_PROTOS +#define RAW_HTABLE_LOG 8 +#define RAW_HTABLE_SIZE (1U << RAW_HTABLE_LOG)
struct raw_hashinfo { spinlock_t lock; - struct hlist_nulls_head ht[RAW_HTABLE_SIZE]; + + struct hlist_nulls_head ht[RAW_HTABLE_SIZE] ____cacheline_aligned; };
+static inline u32 raw_hashfunc(const struct net *net, u32 proto) +{ + return hash_32(net_hash_mix(net) ^ proto, RAW_HTABLE_LOG); +} + static inline void raw_hashinfo_init(struct raw_hashinfo *hashinfo) { int i; diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index 006c1f0ed8b47..2a53a0bf29232 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -93,7 +93,7 @@ int raw_hash_sk(struct sock *sk) struct raw_hashinfo *h = sk->sk_prot->h.raw_hash; struct hlist_nulls_head *hlist;
- hlist = &h->ht[inet_sk(sk)->inet_num & (RAW_HTABLE_SIZE - 1)]; + hlist = &h->ht[raw_hashfunc(sock_net(sk), inet_sk(sk)->inet_num)];
spin_lock(&h->lock); __sk_nulls_add_node_rcu(sk, hlist); @@ -160,9 +160,9 @@ static int icmp_filter(const struct sock *sk, const struct sk_buff *skb) * RFC 1122: SHOULD pass TOS value up to the transport layer. * -> It does. And not only TOS, but all IP header. */ -static int raw_v4_input(struct sk_buff *skb, const struct iphdr *iph, int hash) +static int raw_v4_input(struct net *net, struct sk_buff *skb, + const struct iphdr *iph, int hash) { - struct net *net = dev_net(skb->dev); struct hlist_nulls_head *hlist; struct hlist_nulls_node *hnode; int sdif = inet_sdif(skb); @@ -193,9 +193,10 @@ static int raw_v4_input(struct sk_buff *skb, const struct iphdr *iph, int hash)
int raw_local_deliver(struct sk_buff *skb, int protocol) { - int hash = protocol & (RAW_HTABLE_SIZE - 1); + struct net *net = dev_net(skb->dev);
- return raw_v4_input(skb, ip_hdr(skb), hash); + return raw_v4_input(net, skb, ip_hdr(skb), + raw_hashfunc(net, protocol)); }
static void raw_err(struct sock *sk, struct sk_buff *skb, u32 info) @@ -271,7 +272,7 @@ void raw_icmp_error(struct sk_buff *skb, int protocol, u32 info) struct sock *sk; int hash;
- hash = protocol & (RAW_HTABLE_SIZE - 1); + hash = raw_hashfunc(net, protocol); hlist = &raw_v4_hashinfo.ht[hash];
rcu_read_lock(); diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index 8ffeac7456567..350fb81eda143 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -152,7 +152,7 @@ static bool ipv6_raw_deliver(struct sk_buff *skb, int nexthdr) saddr = &ipv6_hdr(skb)->saddr; daddr = saddr + 1;
- hash = nexthdr & (RAW_HTABLE_SIZE - 1); + hash = raw_hashfunc(net, nexthdr); hlist = &raw_v6_hashinfo.ht[hash]; rcu_read_lock(); sk_nulls_for_each(sk, hnode, hlist) { @@ -338,7 +338,7 @@ void raw6_icmp_error(struct sk_buff *skb, int nexthdr, struct sock *sk; int hash;
- hash = nexthdr & (RAW_HTABLE_SIZE - 1); + hash = raw_hashfunc(net, nexthdr); hlist = &raw_v6_hashinfo.ht[hash]; rcu_read_lock(); sk_nulls_for_each(sk, hnode, hlist) {