diff mbox series

[net-next,12/20] tcp: add RETPOLINE mitigation to sk_backlog_rcv

Message ID 20211115190249.3936899-13-eric.dumazet@gmail.com (mailing list archive)
State Accepted
Delegated to: Netdev Maintainers
Headers show
Series tcp: optimizations for linux-5.17 | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count fail Series longer than 15 patches (and no cover letter)
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 3054 this patch: 3054
netdev/cc_maintainers warning 2 maintainers not CCed: yoshfuji@linux-ipv6.org dsahern@kernel.org
netdev/build_clang success Errors and warnings before: 423 this patch: 423
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 3190 this patch: 3190
netdev/checkpatch warning WARNING: externs should be avoided in .c files WARNING: line length of 83 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Eric Dumazet Nov. 15, 2021, 7:02 p.m. UTC 
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 mbox series

Patch

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;