diff options
| author | Eric Dumazet | 2022-05-13 11:55:44 -0700 |
|---|---|---|
| committer | David S. Miller | 2022-05-16 10:31:06 +0100 |
| commit | e5fccaa1eb7f6116deab0f708a787e2de915869f (patch) | |
| tree | ff0e94f52041131be7d9138d491325335c95f2bc /net/core/sock.c | |
| parent | fdb5fd7f736ec7ae9fb36d2842ea6d9ebc4e7269 (diff) | |
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.c | 11 |
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: |