5 files changed, 15 insertions, 12 deletions

diff --git a/include/net/sock.h b/include/net/sock.h
index 7c0632c7e870..aeeec62992ca 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -507,9 +507,7 @@ int sk_set_peek_off(struct sock *sk, int val);
 static inline int sk_peek_offset(struct sock *sk, int flags)
 {
         if (unlikely(flags & MSG_PEEK)) {
-                s32 off = READ_ONCE(sk->sk_peek_off);
-                if (off >= 0)
-                        return off;
+                return READ_ONCE(sk->sk_peek_off);
         }
 
         return 0;
diff --git a/net/core/datagram.c b/net/core/datagram.c
index ee5647bd91b3..a21ca8dee5ea 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -169,14 +169,20 @@ struct sk_buff *__skb_try_recv_from_queue(struct sock *sk,
                                           int *peeked, int *off, int *err,
                                           struct sk_buff **last)
 {
+        bool peek_at_off = false;
         struct sk_buff *skb;
-        int _off = *off;
+        int _off = 0;
+
+        if (unlikely(flags & MSG_PEEK && *off >= 0)) {
+                peek_at_off = true;
+                _off = *off;
+        }
 
         *last = queue->prev;
         skb_queue_walk(queue, skb) {
                 if (flags & MSG_PEEK) {
-                        if (_off >= skb->len && (skb->len || _off ||
-                                                 skb->peeked)) {
+                        if (peek_at_off && _off >= skb->len &&
+                            (_off || skb->peeked)) {
                                 _off -= skb->len;
                                 continue;
                         }
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index a7c804f73990..cd1d044a7fa5 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1574,7 +1574,8 @@ int udp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
                 return ip_recv_error(sk, msg, len, addr_len);
 
 try_again:
-        peeking = off = sk_peek_offset(sk, flags);
+        peeking = flags & MSG_PEEK;
+        off = sk_peek_offset(sk, flags);
         skb = __skb_recv_udp(sk, flags, noblock, &peeked, &off, &err);
         if (!skb)
                 return err;
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 578142b7ca3e..20039c8501eb 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -362,7 +362,8 @@ int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
                 return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
 
 try_again:
-        peeking = off = sk_peek_offset(sk, flags);
+        peeking = flags & MSG_PEEK;
+        off = sk_peek_offset(sk, flags);
         skb = __skb_recv_udp(sk, flags, noblock, &peeked, &off, &err);
         if (!skb)
                 return err;
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 7b52a380d710..be8982b4f8c0 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -2304,10 +2304,7 @@ static int unix_stream_read_generic(struct unix_stream_read_state *state,
          */
         mutex_lock(&u->iolock);
 
-        if (flags & MSG_PEEK)
-                skip = sk_peek_offset(sk, flags);
-        else
-                skip = 0;
+        skip = max(sk_peek_offset(sk, flags), 0);
 
         do {
                 int chunk;