mwifiex: improve error path handling in usb.c

skb allocated during initialisation is reused for receiving
commands/events by USB interface. We miss to reset skb->data in
failure cases. This patch takes care of it.

Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Kiran Divekar <dkiran@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 17 insertions, 5 deletions

diff --git a/drivers/net/wireless/mwifiex/usb.c b/drivers/net/wireless/mwifiex/usb.c
index e6d796fabab5..22a5916564b8 100644
--- a/drivers/net/wireless/mwifiex/usb.c
+++ b/drivers/net/wireless/mwifiex/usb.c
@@ -49,6 +49,7 @@ static int mwifiex_usb_recv(struct mwifiex_adapter *adapter,
         struct device *dev = adapter->dev;
         u32 recv_type;
         __le32 tmp;
+        int ret;
 
         if (adapter->hs_activated)
                 mwifiex_process_hs_config(adapter);
@@ -69,16 +70,19 @@ static int mwifiex_usb_recv(struct mwifiex_adapter *adapter,
                 case MWIFIEX_USB_TYPE_CMD:
                         if (skb->len > MWIFIEX_SIZE_OF_CMD_BUFFER) {
                                 dev_err(dev, "CMD: skb->len too large\n");
-                                return -1;
+                                ret = -1;
+                                goto exit_restore_skb;
                         } else if (!adapter->curr_cmd) {
                                 dev_dbg(dev, "CMD: no curr_cmd\n");
                                 if (adapter->ps_state == PS_STATE_SLEEP_CFM) {
                                         mwifiex_process_sleep_confirm_resp(
                                                         adapter, skb->data,
                                                         skb->len);
-                                        return 0;
+                                        ret = 0;
+                                        goto exit_restore_skb;
                                 }
-                                return -1;
+                                ret = -1;
+                                goto exit_restore_skb;
                         }
 
                         adapter->curr_cmd->resp_skb = skb;
@@ -87,7 +91,8 @@ static int mwifiex_usb_recv(struct mwifiex_adapter *adapter,
                 case MWIFIEX_USB_TYPE_EVENT:
                         if (skb->len < sizeof(u32)) {
                                 dev_err(dev, "EVENT: skb->len too small\n");
-                                return -1;
+                                ret = -1;
+                                goto exit_restore_skb;
                         }
                         skb_copy_from_linear_data(skb, &tmp, sizeof(u32));
                         adapter->event_cause = le32_to_cpu(tmp);
@@ -95,7 +100,8 @@ static int mwifiex_usb_recv(struct mwifiex_adapter *adapter,
 
                         if (skb->len > MAX_EVENT_SIZE) {
                                 dev_err(dev, "EVENT: event body too large\n");
-                                return -1;
+                                ret = -1;
+                                goto exit_restore_skb;
                         }
 
                         memcpy(adapter->event_body, skb->data +
@@ -124,6 +130,12 @@ static int mwifiex_usb_recv(struct mwifiex_adapter *adapter,
         }
 
         return -EINPROGRESS;
+
+exit_restore_skb:
+        /* The buffer will be reused for further cmds/events */
+        skb_push(skb, INTF_HEADER_LEN);
+
+        return ret;
 }
 
 static void mwifiex_usb_rx_complete(struct urb *urb)