From: Christophe Ricard <christophe.ricard@gmail.com>
Date: Sun, 25 Oct 2015 21:54:20 +0000 (+0100)
Subject: NFC: nci: Fix incorrect data chaining when sending data
X-Git-Tag: v4.2.7~59
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=12cd7a677da483ee9d7e0d97b8fd608753e9a281;p=thirdparty%2Fkernel%2Fstable.git

NFC: nci: Fix incorrect data chaining when sending data

commit 500c4ef02277eaadbfe20537f963b6221f6ac007 upstream.

When sending HCI data over NCI, cmd information should be
present only on the first packet.
Each packet shall be specifically allocated and sent to the
NCI layer.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/nfc/nci/hci.c b/net/nfc/nci/hci.c
index 609f92283d1b7..321889ee21078 100644
--- a/net/nfc/nci/hci.c
+++ b/net/nfc/nci/hci.c
@@ -146,18 +146,18 @@ static int nci_hci_send_data(struct nci_dev *ndev, u8 pipe,
 	if (!conn_info)
 		return -EPROTO;
 
-	skb = nci_skb_alloc(ndev, 2 + conn_info->max_pkt_payload_len +
+	i = 0;
+	skb = nci_skb_alloc(ndev, conn_info->max_pkt_payload_len +
 			    NCI_DATA_HDR_SIZE, GFP_KERNEL);
 	if (!skb)
 		return -ENOMEM;
 
-	skb_reserve(skb, 2 + NCI_DATA_HDR_SIZE);
+	skb_reserve(skb, NCI_DATA_HDR_SIZE + 2);
 	*skb_push(skb, 1) = data_type;
 
-	i = 0;
-	len = conn_info->max_pkt_payload_len;
-
 	do {
+		len = conn_info->max_pkt_payload_len;
+
 		/* If last packet add NCI_HFP_NO_CHAINING */
 		if (i + conn_info->max_pkt_payload_len -
 		    (skb->len + 1) >= data_len) {
@@ -177,9 +177,15 @@ static int nci_hci_send_data(struct nci_dev *ndev, u8 pipe,
 			return r;
 
 		i += len;
+
 		if (i < data_len) {
-			skb_trim(skb, 0);
-			skb_pull(skb, len);
+			skb = nci_skb_alloc(ndev,
+					    conn_info->max_pkt_payload_len +
+					    NCI_DATA_HDR_SIZE, GFP_KERNEL);
+			if (!skb)
+				return -ENOMEM;
+
+			skb_reserve(skb, NCI_DATA_HDR_SIZE + 1);
 		}
 	} while (i < data_len);