rtlwifi: Avoid modifying skbs that are resubmitted

In the case we fail to allocate a new skb, the old skb should
be resubmitted unmodified.

Fixes bug introduced in a9e12869758430424804.

Signed-off-by: Mike McCormack <mikem@ring3k.org>
Acked-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/rtlwifi/pci.c b/drivers/net/wireless/rtlwifi/pci.c
index 3e055c6..9f8ccae 100644 (file)
--- a/drivers/net/wireless/rtlwifi/pci.c
+++ b/drivers/net/wireless/rtlwifi/pci.c
@@ -669,6 +669,19 @@ static void _rtl_pci_rx_interrupt(struct ieee80211_hw *hw)
                                                         &rx_status,
                                                         (u8 *) pdesc, skb);
 
+                       new_skb = dev_alloc_skb(rtlpci->rxbuffersize);
+                       if (unlikely(!new_skb)) {
+                               RT_TRACE(rtlpriv, (COMP_INTR | COMP_RECV),
+                                        DBG_DMESG,
+                                        ("can't alloc skb for rx\n"));
+                               goto done;
+                       }
+
+                       pci_unmap_single(rtlpci->pdev,
+                                        *((dma_addr_t *) skb->cb),
+                                        rtlpci->rxbuffersize,
+                                        PCI_DMA_FROMDEVICE);
+
                        skb_put(skb, rtlpriv->cfg->ops->get_desc((u8 *) pdesc,
                                                         false,
                                                         HW_DESC_RXPKT_LEN));
@@ -685,21 +698,6 @@ static void _rtl_pci_rx_interrupt(struct ieee80211_hw *hw)
                        hdr = rtl_get_hdr(skb);
                        fc = rtl_get_fc(skb);
 
-                       /* try for new buffer - if allocation fails, drop
-                        * frame and reuse old buffer
-                        */
-                       new_skb = dev_alloc_skb(rtlpci->rxbuffersize);
-                       if (unlikely(!new_skb)) {
-                               RT_TRACE(rtlpriv, (COMP_INTR | COMP_RECV),
-                                        DBG_DMESG,
-                                        ("can't alloc skb for rx\n"));
-                               goto done;
-                       }
-                       pci_unmap_single(rtlpci->pdev,
-                                        *((dma_addr_t *) skb->cb),
-                                        rtlpci->rxbuffersize,
-                                        PCI_DMA_FROMDEVICE);
-
                        if (!stats.crc && !stats.hwerror) {
                                memcpy(IEEE80211_SKB_RXCB(skb), &rx_status,
                                       sizeof(rx_status));