6.6-stable review patch. If anyone has any objections, please let me know.
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From: Kuniyuki Iwashima kuniyu@amazon.com
[ 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 kuniyu@amazon.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/unix/af_unix.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 2299a464c602e..4640497c29da4 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);