ch_ktls: packet handling prior to start marker

There could be a case where ACK for tls exchanges prior to start
marker is missed out, and by the time tls is offloaded. This pkt
should not be discarded and handled carefully. It could be
plaintext alone or plaintext + finish as well.

Fixes: 5a4b9fe7 ("cxgb4/chcr: complete record tx handling")
Signed-off-by: Rohit Maheshwari <rohitm@chelsio.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c

@@ -1909,11 +1909,6 @@ static int chcr_ktls_xmit(struct sk_buff *skb, struct net_device *dev)
 			goto out;
 		}
 
-		if (unlikely(tls_record_is_start_marker(record))) {
-			spin_unlock_irqrestore(&tx_ctx->base.lock, flags);
-			atomic64_inc(&port_stats->ktls_tx_skip_no_sync_data);
-			goto out;
-		}
 		tls_end_offset = record->end_seq - tcp_seq;
 
 		pr_debug("seq 0x%x, end_seq 0x%x prev_seq 0x%x, datalen 0x%x\n",
@@ -1938,6 +1933,39 @@ static int chcr_ktls_xmit(struct sk_buff *skb, struct net_device *dev)
 				goto out;
 			}
 		}
+
+		if (unlikely(tls_record_is_start_marker(record))) {
+			atomic64_inc(&port_stats->ktls_tx_skip_no_sync_data);
+			/* If tls_end_offset < data_len, means there is some
+			 * data after start marker, which needs encryption, send
+			 * plaintext first and take skb refcount. else send out
+			 * complete pkt as plaintext.
+			 */
+			if (tls_end_offset < data_len)
+				skb_get(skb);
+			else
+				tls_end_offset = data_len;
+
+			ret = chcr_ktls_tx_plaintxt(tx_info, skb, tcp_seq, mss,
+						    (!th->fin && th->psh), q,
+						    tx_info->port_id, NULL,
+						    tls_end_offset, skb_offset,
+						    0);
+
+			spin_unlock_irqrestore(&tx_ctx->base.lock, flags);
+			if (ret) {
+				/* free the refcount taken earlier */
+				if (tls_end_offset < data_len)
+					dev_kfree_skb_any(skb);
+				goto out;
+			}
+
+			data_len -= tls_end_offset;
+			tcp_seq = record->end_seq;
+			skb_offset += tls_end_offset;
+			continue;
+		}
+
 		/* increase page reference count of the record, so that there
 		 * won't be any chance of page free in middle if in case stack
 		 * receives ACK and try to delete the record.