From d0ed2d2e8e863a9a64c9fc9c08fa68bee546ad00 Mon Sep 17 00:00:00 2001

From: Anthony Liguori <aliguori@us.ibm.com>

Date: Mon, 23 Jan 2012 07:30:43 -0600

Subject: [PATCH 26/26] e1000: bounds packet size against buffer size

Otherwise we can write beyond the buffer and corrupt memory.  This is tracked

as CVE-2012-0029.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

---

 hw/e1000.c |    3 +++

 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/hw/e1000.c b/hw/e1000.c

index 986ed9c..e164d79 100644

--- a/hw/e1000.c

+++ b/hw/e1000.c

@@ -466,6 +466,8 @@ process_tx_desc(E1000State *s, struct e1000_tx_desc *dp)

             bytes = split_size;

             if (tp->size + bytes > msh)

                 bytes = msh - tp->size;

+

+            bytes = MIN(sizeof(tp->data) - tp->size, bytes);

             pci_dma_read(&s->dev, addr, tp->data + tp->size, bytes);

             if ((sz = tp->size + bytes) >= hdr && tp->size < hdr)

                 memmove(tp->header, tp->data, hdr);

@@ -481,6 +483,7 @@ process_tx_desc(E1000State *s, struct e1000_tx_desc *dp)

         // context descriptor TSE is not set, while data descriptor TSE is set

         DBGOUT(TXERR, "TCP segmentaion Error\n");

     } else {

+        split_size = MIN(sizeof(tp->data) - tp->size, split_size);

         pci_dma_read(&s->dev, addr, tp->data + tp->size, split_size);

         tp->size += split_size;

     }

-- 

1.7.7.6