From 996ec22ff576a6cf59d199f523aed57d105a98a8 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Tue, 4 Jun 2024 09:52:36 -0700 Subject: af_unix: Annotate data-races around sk->sk_sndbuf. [ Upstream commit b0632e53e0da8054e36bc973f0eec69d30f1b7c6 ] sk_setsockopt() changes sk->sk_sndbuf under lock_sock(), but it's not used in af_unix.c. Let's use READ_ONCE() to read sk->sk_sndbuf in unix_writable(), unix_dgram_sendmsg(), and unix_stream_sendmsg(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- net/unix/af_unix.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'net') diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 2299a464c602..4640497c29da 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -534,7 +534,7 @@ static int unix_dgram_peer_wake_me(struct sock *sk, struct sock *other) static int unix_writable(const struct sock *sk, unsigned char state) { return state != TCP_LISTEN && - (refcount_read(&sk->sk_wmem_alloc) << 2) <= sk->sk_sndbuf; + (refcount_read(&sk->sk_wmem_alloc) << 2) <= READ_ONCE(sk->sk_sndbuf); } static void unix_write_space(struct sock *sk) @@ -1944,7 +1944,7 @@ static int unix_dgram_sendmsg(struct socket *sock, struct msghdr *msg, } err = -EMSGSIZE; - if (len > sk->sk_sndbuf - 32) + if (len > READ_ONCE(sk->sk_sndbuf) - 32) goto out; if (len > SKB_MAX_ALLOC) { @@ -2223,7 +2223,7 @@ static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg, &err, 0); } else { /* Keep two messages in the pipe so it schedules better */ - size = min_t(int, size, (sk->sk_sndbuf >> 1) - 64); + size = min_t(int, size, (READ_ONCE(sk->sk_sndbuf) >> 1) - 64); /* allow fallback to order-0 allocations */ size = min_t(int, size, SKB_MAX_HEAD(0) + UNIX_SKB_FRAGS_SZ); -- cgit v1.2.3