Merging upstream version 4.19.304.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

2 files changed, 9 insertions, 10 deletions

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index b0dcbb08e..0632b494d 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -594,7 +594,7 @@ static void unix_release_sock(struct sock *sk, int embrion)
 	 *	  What the above comment does talk about? --ANK(980817)
 	 */
 
-	if (unix_tot_inflight)
+	if (READ_ONCE(unix_tot_inflight))
 		unix_gc();		/* Garbage collect fds */
 }
 
@@ -706,7 +706,7 @@ static int unix_set_peek_off(struct sock *sk, int val)
 	if (mutex_lock_interruptible(&u->iolock))
 		return -EINTR;
 
-	sk->sk_peek_off = val;
+	WRITE_ONCE(sk->sk_peek_off, val);
 	mutex_unlock(&u->iolock);
 
 	return 0;
@@ -1984,6 +1984,7 @@ static ssize_t unix_stream_sendpage(struct socket *socket, struct page *page,
 
 	if (false) {
 alloc_skb:
+		spin_unlock(&other->sk_receive_queue.lock);
 		unix_state_unlock(other);
 		mutex_unlock(&unix_sk(other)->iolock);
 		newskb = sock_alloc_send_pskb(sk, 0, 0, flags & MSG_DONTWAIT,
@@ -2023,6 +2024,7 @@ alloc_skb:
 		init_scm = false;
 	}
 
+	spin_lock(&other->sk_receive_queue.lock);
 	skb = skb_peek_tail(&other->sk_receive_queue);
 	if (tail && tail == skb) {
 		skb = newskb;
@@ -2053,14 +2055,11 @@ alloc_skb:
 	refcount_add(size, &sk->sk_wmem_alloc);
 
 	if (newskb) {
-		err = unix_scm_to_skb(&scm, skb, false);
-		if (err)
-			goto err_state_unlock;
-		spin_lock(&other->sk_receive_queue.lock);
+		unix_scm_to_skb(&scm, skb, false);
 		__skb_queue_tail(&other->sk_receive_queue, newskb);
-		spin_unlock(&other->sk_receive_queue.lock);
 	}
 
+	spin_unlock(&other->sk_receive_queue.lock);
 	unix_state_unlock(other);
 	mutex_unlock(&unix_sk(other)->iolock);
 
diff --git a/net/unix/scm.c b/net/unix/scm.c
index a07b2efbf..ac206bfdb 100644
--- a/net/unix/scm.c
+++ b/net/unix/scm.c
@@ -59,7 +59,7 @@ void unix_inflight(struct user_struct *user, struct file *fp)
 		/* Paired with READ_ONCE() in wait_for_unix_gc() */
 		WRITE_ONCE(unix_tot_inflight, unix_tot_inflight + 1);
 	}
-	user->unix_inflight++;
+	WRITE_ONCE(user->unix_inflight, user->unix_inflight + 1);
 	spin_unlock(&unix_gc_lock);
 }
 
@@ -80,7 +80,7 @@ void unix_notinflight(struct user_struct *user, struct file *fp)
 		/* Paired with READ_ONCE() in wait_for_unix_gc() */
 		WRITE_ONCE(unix_tot_inflight, unix_tot_inflight - 1);
 	}
-	user->unix_inflight--;
+	WRITE_ONCE(user->unix_inflight, user->unix_inflight - 1);
 	spin_unlock(&unix_gc_lock);
 }
 
@@ -94,7 +94,7 @@ static inline bool too_many_unix_fds(struct task_struct *p)
 {
 	struct user_struct *user = current_user();
 
-	if (unlikely(user->unix_inflight > task_rlimit(p, RLIMIT_NOFILE)))
+	if (unlikely(READ_ONCE(user->unix_inflight) > task_rlimit(p, RLIMIT_NOFILE)))
 		return !capable(CAP_SYS_RESOURCE) && !capable(CAP_SYS_ADMIN);
 	return false;
 }