[PATCH net-next 12/20] tcp: add RETPOLINE mitigation to sk_backlog_rcv
From: Eric Dumazet <hidden>
Date: 2021-11-15 20:09:32
Subsystem:
networking [general], networking [sockets], networking [tcp], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Kuniyuki Iwashima, Willem de Bruijn, Neal Cardwell, Linus Torvalds
From: Eric Dumazet <edumazet@google.com> Use INDIRECT_CALL_INET() to avoid an indirect call when/if CONFIG_RETPOLINE=y Signed-off-by: Eric Dumazet <edumazet@google.com> --- include/net/sock.h | 8 +++++++- net/core/sock.c | 5 ++++- net/ipv6/tcp_ipv6.c | 5 +++-- 3 files changed, 14 insertions(+), 4 deletions(-)
diff --git a/include/net/sock.h b/include/net/sock.h
index cb97c448472aa5af3055916df844cbe422578190..2d40fe4c7718ee702bf7e5a847ceff6f8f2f5b7d 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h@@ -1018,12 +1018,18 @@ static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *s int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); +INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)); +INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)); + static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) { if (sk_memalloc_socks() && skb_pfmemalloc(skb)) return __sk_backlog_rcv(sk, skb); - return sk->sk_backlog_rcv(sk, skb); + return INDIRECT_CALL_INET(sk->sk_backlog_rcv, + tcp_v6_do_rcv, + tcp_v4_do_rcv, + sk, skb); } static inline void sk_incoming_cpu_update(struct sock *sk)
diff --git a/net/core/sock.c b/net/core/sock.c
index 99738e14224c44e5aa4b88857620fb162e9c265f..c57d9883f62c75f522b7f6bc68451aaf8429dc83 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c@@ -327,7 +327,10 @@ int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); noreclaim_flag = memalloc_noreclaim_save(); - ret = sk->sk_backlog_rcv(sk, skb); + ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv, + tcp_v6_do_rcv, + tcp_v4_do_rcv, + sk, skb); memalloc_noreclaim_restore(noreclaim_flag); return ret;
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 1f1a89f096de9f77ab1bd2d871eb90a3f12e91e0..f41f14b701233dd2d0f5ad464a623a5ba9774763 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c@@ -72,7 +72,7 @@ static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb); static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, struct request_sock *req); -static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb); +INDIRECT_CALLABLE_SCOPE int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb); static const struct inet_connection_sock_af_ops ipv6_mapped; const struct inet_connection_sock_af_ops ipv6_specific;
@@ -1466,7 +1466,8 @@ INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *, * This is because we cannot sleep with the original spinlock * held. */ -static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) +INDIRECT_CALLABLE_SCOPE +int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) { struct ipv6_pinfo *np = tcp_inet6_sk(sk); struct sk_buff *opt_skb = NULL;
--
2.34.0.rc1.387.gb447b232ab-goog