e1000e: prevent null ptr dereference in e1000_tx_queue()
tx_desc can be dereferenced as a null pointer when count is passed in
as 0.
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Emil Tantilov <emil.s.tantilov@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/e1000e/netdev.c b/drivers/net/e1000e/netdev.c
index 393b76d..4bf843a 100644
--- a/drivers/net/e1000e/netdev.c
+++ b/drivers/net/e1000e/netdev.c
@@ -4629,7 +4629,7 @@
i = tx_ring->next_to_use;
- while (count--) {
+ do {
buffer_info = &tx_ring->buffer_info[i];
tx_desc = E1000_TX_DESC(*tx_ring, i);
tx_desc->buffer_addr = cpu_to_le64(buffer_info->dma);
@@ -4640,7 +4640,7 @@
i++;
if (i == tx_ring->count)
i = 0;
- }
+ } while (--count > 0);
tx_desc->lower.data |= cpu_to_le32(adapter->txd_cmd);