summaryrefslogtreecommitdiff
path: root/net/core/sock.c
diff options
context:
space:
mode:
authorEric Dumazet <edumazet@google.com>2022-05-13 21:55:44 +0300
committerDavid S. Miller <davem@davemloft.net>2022-05-16 12:31:06 +0300
commite5fccaa1eb7f6116deab0f708a787e2de915869f (patch)
treeff0e94f52041131be7d9138d491325335c95f2bc /net/core/sock.c
parentfdb5fd7f736ec7ae9fb36d2842ea6d9ebc4e7269 (diff)
downloadlinux-e5fccaa1eb7f6116deab0f708a787e2de915869f.tar.xz
net: core: add READ_ONCE/WRITE_ONCE annotations for sk->sk_bound_dev_if
sock_bindtoindex_locked() needs to use WRITE_ONCE(sk->sk_bound_dev_if, val), because other cpus/threads might locklessly read this field. sock_getbindtodevice(), sock_getsockopt() need READ_ONCE() because they run without socket lock held. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/sock.c')
-rw-r--r--net/core/sock.c11
1 files changed, 7 insertions, 4 deletions
diff --git a/net/core/sock.c b/net/core/sock.c
index 24a46a1e4f28..2ff40dd0a7a6 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -635,7 +635,9 @@ static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
if (ifindex < 0)
goto out;
- sk->sk_bound_dev_if = ifindex;
+ /* Paired with all READ_ONCE() done locklessly. */
+ WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
+
if (sk->sk_prot->rehash)
sk->sk_prot->rehash(sk);
sk_dst_reset(sk);
@@ -713,10 +715,11 @@ static int sock_getbindtodevice(struct sock *sk, char __user *optval,
{
int ret = -ENOPROTOOPT;
#ifdef CONFIG_NETDEVICES
+ int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
struct net *net = sock_net(sk);
char devname[IFNAMSIZ];
- if (sk->sk_bound_dev_if == 0) {
+ if (bound_dev_if == 0) {
len = 0;
goto zero;
}
@@ -725,7 +728,7 @@ static int sock_getbindtodevice(struct sock *sk, char __user *optval,
if (len < IFNAMSIZ)
goto out;
- ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
+ ret = netdev_get_name(net, devname, bound_dev_if);
if (ret)
goto out;
@@ -1861,7 +1864,7 @@ int sock_getsockopt(struct socket *sock, int level, int optname,
break;
case SO_BINDTOIFINDEX:
- v.val = sk->sk_bound_dev_if;
+ v.val = READ_ONCE(sk->sk_bound_dev_if);
break;
case SO_NETNS_COOKIE: