diff mbox series

[1/4] qmi_wwan: add support for QMAP padding in the RX path

Message ID 23e6f9adb545bf29a6dd13aa920b94d70ea548c0.1560287477.git.rspmn@arcor.de
State Accepted
Delegated to: David Miller
Headers show
Series qmi_wwan: fix QMAP handling | expand

Commit Message

Reinhard Speyerer June 12, 2019, 5:02 p.m. UTC 
The QMAP code in the qmi_wwan driver is based on the CodeAurora GobiNet
driver which does not process QMAP padding in the RX path correctly.
Add support for QMAP padding to qmimux_rx_fixup() according to the
description of the rmnet driver.

Fixes: c6adf77953bc ("net: usb: qmi_wwan: add qmap mux protocol support")
Cc: Daniele Palmas <dnlplm@gmail.com>
Signed-off-by: Reinhard Speyerer <rspmn@arcor.de>
---
 drivers/net/usb/qmi_wwan.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c
index d9a6699abe59..fd3d078a1923 100644
--- a/drivers/net/usb/qmi_wwan.c
+++ b/drivers/net/usb/qmi_wwan.c
@@ -153,7 +153,7 @@  static bool qmimux_has_slaves(struct usbnet *dev)
 
 static int qmimux_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
 {
-	unsigned int len, offset = 0;
+	unsigned int len, offset = 0, pad_len, pkt_len;
 	struct qmimux_hdr *hdr;
 	struct net_device *net;
 	struct sk_buff *skbn;
@@ -171,10 +171,16 @@  static int qmimux_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
 		if (hdr->pad & 0x80)
 			goto skip;
 
+		/* extract padding length and check for valid length info */
+		pad_len = hdr->pad & 0x3f;
+		if (len == 0 || pad_len >= len)
+			goto skip;
+		pkt_len = len - pad_len;
+
 		net = qmimux_find_dev(dev, hdr->mux_id);
 		if (!net)
 			goto skip;
-		skbn = netdev_alloc_skb(net, len);
+		skbn = netdev_alloc_skb(net, pkt_len);
 		if (!skbn)
 			return 0;
 		skbn->dev = net;
@@ -191,7 +197,7 @@  static int qmimux_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
 			goto skip;
 		}
 
-		skb_put_data(skbn, skb->data + offset + qmimux_hdr_sz, len);
+		skb_put_data(skbn, skb->data + offset + qmimux_hdr_sz, pkt_len);
 		if (netif_rx(skbn) != NET_RX_SUCCESS)
 			return 0;