From: Eric Dumazet <edumazet@google.com>
Date: Fri, 28 Jul 2023 15:03:16 +0000 (+0000)
Subject: net: add missing data-race annotations around sk->sk_peek_off
X-Git-Tag: v4.14.322~21
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=46ca66e811f18c7d3970104b9769a9f19dd0f111;p=thirdparty%2Fkernel%2Fstable.git

net: add missing data-race annotations around sk->sk_peek_off

[ Upstream commit 11695c6e966b0ec7ed1d16777d294cef865a5c91 ]

sk_getsockopt() runs locklessly, thus we need to annotate the read
of sk->sk_peek_off.

While we are at it, add corresponding annotations to sk_set_peek_off()
and unix_set_peek_off().

Fixes: b9bb53f3836f ("sock: convert sk_peek_offset functions to WRITE_ONCE")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/net/core/sock.c b/net/core/sock.c
index 5991b09c75f4d..d938b7f2bac32 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1329,7 +1329,7 @@ int sock_getsockopt(struct socket *sock, int level, int optname,
 		if (!sock->ops->set_peek_off)
 			return -EOPNOTSUPP;
 
-		v.val = sk->sk_peek_off;
+		v.val = READ_ONCE(sk->sk_peek_off);
 		break;
 	case SO_NOFCS:
 		v.val = sock_flag(sk, SOCK_NOFCS);
@@ -2480,7 +2480,7 @@ EXPORT_SYMBOL(__sk_mem_reclaim);
 
 int sk_set_peek_off(struct sock *sk, int val)
 {
-	sk->sk_peek_off = val;
+	WRITE_ONCE(sk->sk_peek_off, val);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(sk_set_peek_off);
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 375d4e20efd6b..c4ec2c2e4c861 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -701,7 +701,7 @@ static int unix_set_peek_off(struct sock *sk, int val)
 	if (mutex_lock_interruptible(&u->iolock))
 		return -EINTR;
 
-	sk->sk_peek_off = val;
+	WRITE_ONCE(sk->sk_peek_off, val);
 	mutex_unlock(&u->iolock);
 
 	return 0;