From e84a4927a404f369c842c19de93b216627fcc690 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 20 Jun 2025 13:30:00 +0000 Subject: net: annotate races around sk->sk_uid MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit sk->sk_uid can be read while another thread changes its value in sockfs_setattr(). Add sk_uid(const struct sock *sk) helper to factorize the needed READ_ONCE() annotations, and add corresponding WRITE_ONCE() where needed. Fixes: 86741ec25462 ("net: core: Add a UID field to struct sock.") Signed-off-by: Eric Dumazet Cc: Lorenzo Colitti Reviewed-by: Maciej Żenczykowski Link: https://patch.msgid.link/20250620133001.4090592-2-edumazet@google.com Signed-off-by: Jakub Kicinski --- net/socket.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'net/socket.c') diff --git a/net/socket.c b/net/socket.c index 2cab805943c0..682969deaed3 100644 --- a/net/socket.c +++ b/net/socket.c @@ -592,10 +592,12 @@ static int sockfs_setattr(struct mnt_idmap *idmap, if (!err && (iattr->ia_valid & ATTR_UID)) { struct socket *sock = SOCKET_I(d_inode(dentry)); - if (sock->sk) - sock->sk->sk_uid = iattr->ia_uid; - else + if (sock->sk) { + /* Paired with READ_ONCE() in sk_uid() */ + WRITE_ONCE(sock->sk->sk_uid, iattr->ia_uid); + } else { err = -ENOENT; + } } return err; -- cgit v1.2.3