ixgbevf: Add fix to VF to handle multi-descriptor buffers

This change fixes the ixgbevf driver so that it can correctly drop a frame
should it receive a jumbo frame.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

2 files changed, 17 insertions, 2 deletions

diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf.h b/drivers/net/ethernet/intel/ixgbevf/ixgbevf.h
index eb26fda63c99..383b4e1cd175 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf.h
+++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf.h
@@ -261,6 +261,11 @@ enum ixbgevf_state_t {
         __IXGBEVF_DOWN
 };
 
+struct ixgbevf_cb {
+        struct sk_buff *prev;
+};
+#define IXGBE_CB(skb) ((struct ixgbevf_cb *)(skb)->cb)
+
 enum ixgbevf_boards {
         board_82599_vf,
         board_X540_vf,
diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
index 37bbd86529e3..2ba15ae2335c 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
+++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
@@ -433,11 +433,21 @@ static bool ixgbevf_clean_rx_irq(struct ixgbevf_q_vector *q_vector,
 
                 if (!(staterr & IXGBE_RXD_STAT_EOP)) {
                         skb->next = next_buffer->skb;
-                        skb->next->prev = skb;
+                        IXGBE_CB(skb->next)->prev = skb;
                         adapter->non_eop_descs++;
                         goto next_desc;
                 }
 
+                /* we should not be chaining buffers, if we did drop the skb */
+                if (IXGBE_CB(skb)->prev) {
+                        do {
+                                struct sk_buff *this = skb;
+                                skb = IXGBE_CB(skb)->prev;
+                                dev_kfree_skb(this);
+                        } while (skb);
+                        goto next_desc;
+                }
+
                 /* ERR_MASK will only have valid bits if EOP set */
                 if (unlikely(staterr & IXGBE_RXDADV_ERR_FRAME_ERR_MASK)) {
                         dev_kfree_skb_irq(skb);
@@ -1439,7 +1449,7 @@ static void ixgbevf_clean_rx_ring(struct ixgbevf_adapter *adapter,
                         rx_buffer_info->skb = NULL;
                         do {
                                 struct sk_buff *this = skb;
-                                skb = skb->prev;
+                                skb = IXGBE_CB(skb)->prev;
                                 dev_kfree_skb(this);
                         } while (skb);
                 }