[PATCH 6.1 125/473] net: remove duplicate reuseport_lookup functions

Greg Kroah-Hartman
2024-06-06T14:14:08Z

From: Lorenz Bauer <lmb@isovalent.com>

[ Upstream commit 0f495f7617229772403e683033abc473f0f0553c ]

There are currently four copies of reuseport_lookup: one each for
(TCP, UDP)x(IPv4, IPv6). This forces us to duplicate all callers of
those functions as well. This is already the case for sk_lookup
helpers (inet,inet6,udp4,udp6)_lookup_run_bpf.

There are two differences between the reuseport_lookup helpers:

1. They call different hash functions depending on protocol
2. UDP reuseport_lookup checks that sk_state != TCP_ESTABLISHED

Move the check for sk_state into the caller and use the INDIRECT_CALL
infrastructure to cut down the helpers to one per IP version.

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Lorenz Bauer <lmb@isovalent.com>
Link: https://lore.kernel.org/r/20230720-so-reuseport-v6-4-7021b683cdae@isovalent.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Stable-dep-of: 50aee97d1511 ("udp: Avoid call to compute_score on multiple sites")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/net/inet6_hashtables.h | 11 ++++++++-
include/net/inet_hashtables.h | 15 ++++++++-----
net/ipv4/inet_hashtables.c | 20 +++++++++++------
net/ipv4/udp.c | 34 +++++++++++-----------------
net/ipv6/inet6_hashtables.c | 14 ++++++++----
net/ipv6/udp.c | 41 +++++++++++++---------------------
6 files changed, 72 insertions(+), 63 deletions(-)

diff --git a/include/net/inet6_hashtables.h b/include/net/inet6_hashtables.h
index 032ddab48f8f8..f89320b6fee31 100644
--- a/include/net/inet6_hashtables.h
+++ b/include/net/inet6_hashtables.h
@@ -48,12 +48,21 @@ struct sock *__inet6_lookup_established(struct net *net,
const u16 hnum, const int dif,
const int sdif);

+typedef u32 (inet6_ehashfn_t)(const struct net *net,
+ const struct in6_addr *laddr, const u16 lport,
+ const struct in6_addr *faddr, const __be16 fport);
+
+inet6_ehashfn_t inet6_ehashfn;
+
+INDIRECT_CALLABLE_DECLARE(inet6_ehashfn_t udp6_ehashfn);
+
struct sock *inet6_lookup_reuseport(struct net *net, struct sock *sk,
struct sk_buff *skb, int doff,
const struct in6_addr *saddr,
__be16 sport,
const struct in6_addr *daddr,
- unsigned short hnum);
+ unsigned short hnum,
+ inet6_ehashfn_t *ehashfn);

struct sock *inet6_lookup_listener(struct net *net,
struct inet_hashinfo *hashinfo,
diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h
index 8734f3488f5d0..ddfa2e67fdb51 100644
--- a/include/net/inet_hashtables.h
+++ b/include/net/inet_hashtables.h
@@ -379,10 +379,19 @@ struct sock *__inet_lookup_established(struct net *net,
const __be32 daddr, const u16 hnum,
const int dif, const int sdif);

+typedef u32 (inet_ehashfn_t)(const struct net *net,
+ const __be32 laddr, const __u16 lport,
+ const __be32 faddr, const __be16 fport);
+
+inet_ehashfn_t inet_ehashfn;
+
+INDIRECT_CALLABLE_DECLARE(inet_ehashfn_t udp_ehashfn);
+
struct sock *inet_lookup_reuseport(struct net *net, struct sock *sk,
struct sk_buff *skb, int doff,
__be32 saddr, __be16 sport,
- __be32 daddr, unsigned short hnum);
+ __be32 daddr, unsigned short hnum,
+ inet_ehashfn_t *ehashfn);

static inline struct sock *
inet_lookup_established(struct net *net, struct inet_hashinfo *hashinfo,
@@ -453,10 +462,6 @@ static inline struct sock *__inet_lookup_skb(struct inet_hashinfo *hashinfo,
refcounted);
}

-u32 inet6_ehashfn(const struct net *net,
- const struct in6_addr *laddr, const u16 lport,
- const struct in6_addr *faddr, const __be16 fport);
-
static inline void sk_daddr_set(struct sock *sk, __be32 addr)
{
sk->sk_daddr = addr; /* alias of inet_daddr */
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index eb8da8d113fe2..321f509f23473 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -28,9 +28,9 @@
#include <net/tcp.h>
#include <net/sock_reuseport.h>

-static u32 inet_ehashfn(const struct net *net, const __be32 laddr,
- const __u16 lport, const __be32 faddr,
- const __be16 fport)
+u32 inet_ehashfn(const struct net *net, const __be32 laddr,
+ const __u16 lport, const __be32 faddr,
+ const __be16 fport)
{
static u32 inet_ehash_secret __read_mostly;

@@ -39,6 +39,7 @@ static u32 inet_ehashfn(const struct net *net, const __be32 laddr,
return __inet_ehashfn(laddr, lport, faddr, fport,
inet_ehash_secret + net_hash_mix(net));
}
+EXPORT_SYMBOL_GPL(inet_ehashfn);

/* This function handles inet_sock, but also timewait and request sockets
* for IPv4/IPv6.
@@ -338,16 +339,20 @@ static inline int compute_score(struct sock *sk, struct net *net,
return score;
}

+INDIRECT_CALLABLE_DECLARE(inet_ehashfn_t udp_ehashfn);
+
struct sock *inet_lookup_reuseport(struct net *net, struct sock *sk,
struct sk_buff *skb, int doff,
__be32 saddr, __be16 sport,
- __be32 daddr, unsigned short hnum)
+ __be32 daddr, unsigned short hnum,
+ inet_ehashfn_t *ehashfn)
{
struct sock *reuse_sk = NULL;
u32 phash;

if (sk->sk_reuseport) {
- phash = inet_ehashfn(net, daddr, hnum, saddr, sport);
+ phash = INDIRECT_CALL_2(ehashfn, udp_ehashfn, inet_ehashfn,
+ net, daddr, hnum, saddr, sport);
reuse_sk = reuseport_select_sock(sk, phash, skb, doff);
}
return reuse_sk;
@@ -377,7 +382,7 @@ static struct sock *inet_lhash2_lookup(struct net *net,
score = compute_score(sk, net, hnum, daddr, dif, sdif);
if (score > hiscore) {
result = inet_lookup_reuseport(net, sk, skb, doff,
- saddr, sport, daddr, hnum);
+ saddr, sport, daddr, hnum, inet_ehashfn);
if (result)
return result;

@@ -406,7 +411,8 @@ static inline struct sock *inet_lookup_run_bpf(struct net *net,
if (no_reuseport || IS_ERR_OR_NULL(sk))
return sk;

- reuse_sk = inet_lookup_reuseport(net, sk, skb, doff, saddr, sport, daddr, hnum);
+ reuse_sk = inet_lookup_reuseport(net, sk, skb, doff, saddr, sport, daddr, hnum,
+ inet_ehashfn);
if (reuse_sk)
sk = reuse_sk;
return sk;
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 39fae7581d350..3dc4eaddb598a 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -400,9 +400,9 @@ static int compute_score(struct sock *sk, struct net *net,
return score;
}

-static u32 udp_ehashfn(const struct net *net, const __be32 laddr,
- const __u16 lport, const __be32 faddr,
- const __be16 fport)
+INDIRECT_CALLABLE_SCOPE
+u32 udp_ehashfn(const struct net *net, const __be32 laddr, const __u16 lport,
+ const __be32 faddr, const __be16 fport)
{
static u32 udp_ehash_secret __read_mostly;

@@ -412,22 +412,6 @@ static u32 udp_ehashfn(const struct net *net, const __be32 laddr,
udp_ehash_secret + net_hash_mix(net));
}

-static struct sock *lookup_reuseport(struct net *net, struct sock *sk,
- struct sk_buff *skb,
- __be32 saddr, __be16 sport,
- __be32 daddr, unsigned short hnum)
-{
- struct sock *reuse_sk = NULL;
- u32 hash;
-
- if (sk->sk_reuseport && sk->sk_state != TCP_ESTABLISHED) {
- hash = udp_ehashfn(net, daddr, hnum, saddr, sport);
- reuse_sk = reuseport_select_sock(sk, hash, skb,
- sizeof(struct udphdr));
- }
- return reuse_sk;
-}
-
/* called with rcu_read_lock() */
static struct sock *udp4_lib_lookup2(struct net *net,
__be32 saddr, __be16 sport,
@@ -446,7 +430,14 @@ static struct sock *udp4_lib_lookup2(struct net *net,
daddr, hnum, dif, sdif);
if (score > badness) {
badness = score;
- result = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum);
+
+ if (sk->sk_state == TCP_ESTABLISHED) {
+ result = sk;
+ continue;
+ }
+
+ result = inet_lookup_reuseport(net, sk, skb, sizeof(struct udphdr),
+ saddr, sport, daddr, hnum, udp_ehashfn);
if (!result) {
result = sk;
continue;
@@ -485,7 +476,8 @@ static struct sock *udp4_lookup_run_bpf(struct net *net,
if (no_reuseport || IS_ERR_OR_NULL(sk))
return sk;

- reuse_sk = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum);
+ reuse_sk = inet_lookup_reuseport(net, sk, skb, sizeof(struct udphdr),
+ saddr, sport, daddr, hnum, udp_ehashfn);
if (reuse_sk)
sk = reuse_sk;
return sk;
diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
index b7c56867314ed..3616225c89ef6 100644
--- a/net/ipv6/inet6_hashtables.c
+++ b/net/ipv6/inet6_hashtables.c
@@ -39,6 +39,7 @@ u32 inet6_ehashfn(const struct net *net,
return __inet6_ehashfn(lhash, lport, fhash, fport,
inet6_ehash_secret + net_hash_mix(net));
}
+EXPORT_SYMBOL_GPL(inet6_ehashfn);

/*
* Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
@@ -111,18 +112,22 @@ static inline int compute_score(struct sock *sk, struct net *net,
return score;
}

+INDIRECT_CALLABLE_DECLARE(inet6_ehashfn_t udp6_ehashfn);
+
struct sock *inet6_lookup_reuseport(struct net *net, struct sock *sk,
struct sk_buff *skb, int doff,
const struct in6_addr *saddr,
__be16 sport,
const struct in6_addr *daddr,
- unsigned short hnum)
+ unsigned short hnum,
+ inet6_ehashfn_t *ehashfn)
{
struct sock *reuse_sk = NULL;
u32 phash;

if (sk->sk_reuseport) {
- phash = inet6_ehashfn(net, daddr, hnum, saddr, sport);
+ phash = INDIRECT_CALL_INET(ehashfn, udp6_ehashfn, inet6_ehashfn,
+ net, daddr, hnum, saddr, sport);
reuse_sk = reuseport_select_sock(sk, phash, skb, doff);
}
return reuse_sk;
@@ -145,7 +150,7 @@ static struct sock *inet6_lhash2_lookup(struct net *net,
score = compute_score(sk, net, hnum, daddr, dif, sdif);
if (score > hiscore) {
result = inet6_lookup_reuseport(net, sk, skb, doff,
- saddr, sport, daddr, hnum);
+ saddr, sport, daddr, hnum, inet6_ehashfn);
if (result)
return result;

@@ -176,7 +181,8 @@ static inline struct sock *inet6_lookup_run_bpf(struct net *net,
if (no_reuseport || IS_ERR_OR_NULL(sk))
return sk;

- reuse_sk = inet6_lookup_reuseport(net, sk, skb, doff, saddr, sport, daddr, hnum);
+ reuse_sk = inet6_lookup_reuseport(net, sk, skb, doff,
+ saddr, sport, daddr, hnum, inet6_ehashfn);
if (reuse_sk)
sk = reuse_sk;
return sk;
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 504ea27d08fb0..6f270fda3cbe0 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -70,11 +70,12 @@ int udpv6_init_sock(struct sock *sk)
return 0;
}

-static u32 udp6_ehashfn(const struct net *net,
- const struct in6_addr *laddr,
- const u16 lport,
- const struct in6_addr *faddr,
- const __be16 fport)
+INDIRECT_CALLABLE_SCOPE
+u32 udp6_ehashfn(const struct net *net,
+ const struct in6_addr *laddr,
+ const u16 lport,
+ const struct in6_addr *faddr,
+ const __be16 fport)
{
static u32 udp6_ehash_secret __read_mostly;
static u32 udp_ipv6_hash_secret __read_mostly;
@@ -159,24 +160,6 @@ static int compute_score(struct sock *sk, struct net *net,
return score;
}

-static struct sock *lookup_reuseport(struct net *net, struct sock *sk,
- struct sk_buff *skb,
- const struct in6_addr *saddr,
- __be16 sport,
- const struct in6_addr *daddr,
- unsigned int hnum)
-{
- struct sock *reuse_sk = NULL;
- u32 hash;
-
- if (sk->sk_reuseport && sk->sk_state != TCP_ESTABLISHED) {
- hash = udp6_ehashfn(net, daddr, hnum, saddr, sport);
- reuse_sk = reuseport_select_sock(sk, hash, skb,
- sizeof(struct udphdr));
- }
- return reuse_sk;
-}
-
/* called with rcu_read_lock() */
static struct sock *udp6_lib_lookup2(struct net *net,
const struct in6_addr *saddr, __be16 sport,
@@ -194,7 +177,14 @@ static struct sock *udp6_lib_lookup2(struct net *net,
daddr, hnum, dif, sdif);
if (score > badness) {
badness = score;
- result = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum);
+
+ if (sk->sk_state == TCP_ESTABLISHED) {
+ result = sk;
+ continue;
+ }
+
+ result = inet6_lookup_reuseport(net, sk, skb, sizeof(struct udphdr),
+ saddr, sport, daddr, hnum, udp6_ehashfn);
if (!result) {
result = sk;
continue;
@@ -234,7 +224,8 @@ static inline struct sock *udp6_lookup_run_bpf(struct net *net,
if (no_reuseport || IS_ERR_OR_NULL(sk))
return sk;

- reuse_sk = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum);
+ reuse_sk = inet6_lookup_reuseport(net, sk, skb, sizeof(struct udphdr),
+ saddr, sport, daddr, hnum, udp6_ehashfn);
if (reuse_sk)
sk = reuse_sk;
return sk;
--
2.43.0