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>

1 files changed, 13 insertions, 15 deletions

diff --git a/drivers/net/wireless/rtlwifi/pci.c b/drivers/net/wireless/rtlwifi/pci.c
index 3e055c6bad36..9f8ccae93317 100644
--- 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));