[Xen-changelog] [qemu-xen-4.0-testing] e1000: bounds packet size against buffer size

[patchbot@xxxxxxx]

commit 36984c285a765541b04f378bfa84d2c850c167d3
Author: Ian Campbell <Ian.Campbell@xxxxxxxxxx>
Date:   Thu Feb 2 13:47:06 2012 +0000

    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@xxxxxxxxxx>
    
    (Backported from qemu upstream 65f82df0d7a71ce1b10cd4c5ab08888d176ac840
     by Ian Campbell.)
    
    Signed-off-by: Ian Campbell <Ian.Campbell@xxxxxxxxxx>
    (cherry picked from commit ebe37b2a3f844bad02dcc30d081f39eda06118f8)
---
 hw/e1000.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/hw/e1000.c b/hw/e1000.c
index 1644201..e77c81e 100644
--- a/hw/e1000.c
+++ b/hw/e1000.c
@@ -432,6 +432,8 @@ 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);
             cpu_physical_memory_read(addr, tp->data + tp->size, bytes);
             if ((sz = tp->size + bytes) >= hdr && tp->size < hdr)
                 memmove(tp->header, tp->data, hdr);
@@ -447,6 +449,7 @@ 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);
         cpu_physical_memory_read(addr, tp->data + tp->size, split_size);
         tp->size += split_size;
     }
--
generated by git-patchbot for /home/xen/git/qemu-xen-4.0-testing.git

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