chelsio/chtls: fix tls record info to user

[ Upstream commit 4f3391c ]

chtls_pt_recvmsg() receives a skb with tls header and subsequent
skb with data, need to finalize the data copy whenever next skb
with tls header is available. but here current tls header is
overwritten by next available tls header, ends up corrupting
user buffer data. fixing it by finalizing current record whenever
next skb contains tls header.

v1->v2:
- Improved commit message.

Fixes: 17a7d24 ("crypto: chtls - generic handling of data and hdr")
Signed-off-by: Vinay Kumar Yadav <vinay.yadav@chelsio.com>
Link: https://lore.kernel.org/r/20201022190556.21308-1-vinay.yadav@chelsio.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/crypto/chelsio/chtls/chtls_io.c

@@ -1585,6 +1585,7 @@ static int chtls_pt_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 			tp->urg_data = 0;
 
 		if ((avail + offset) >= skb->len) {
+			struct sk_buff *next_skb;
 			if (ULP_SKB_CB(skb)->flags & ULPCB_FLAG_TLS_HDR) {
 				tp->copied_seq += skb->len;
 				hws->rcvpld = skb->hdr_len;
@@ -1595,8 +1596,10 @@ static int chtls_pt_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 			chtls_free_skb(sk, skb);
 			buffers_freed++;
 			hws->copied_seq = 0;
-			if (copied >= target &&
-			    !skb_peek(&sk->sk_receive_queue))
+			next_skb = skb_peek(&sk->sk_receive_queue);
+			if (copied >= target && !next_skb)
+				break;
+			if (ULP_SKB_CB(next_skb)->flags & ULPCB_FLAG_TLS_HDR)
 				break;
 		}
 	} while (len > 0);