From faa093fc3b71b073a73f800785c3cdabe5a91cc3 Mon Sep 17 00:00:00 2001
From: Kevin Wolf <kwolf@redhat.com>
Date: Tue, 25 Mar 2014 14:23:21 +0100
Subject: [PATCH 14/49] bochs: Fix bitmap offset calculation

RH-Author: Kevin Wolf <kwolf@redhat.com>
Message-id: <1395753835-7591-15-git-send-email-kwolf@redhat.com>
Patchwork-id: n/a
O-Subject: [virt-devel] [EMBARGOED RHEL-7.0 qemu-kvm PATCH 14/48] bochs: Fix bitmap offset calculation
Bugzilla: 1066691
RH-Acked-by: Jeff Cody <jcody@redhat.com>
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1066691
Upstream status: Series embargoed

32 bit truncation could let us access the wrong offset in the image.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/bochs.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/block/bochs.c b/block/bochs.c
index 0ec980a..5c74223 100644
--- a/block/bochs.c
+++ b/block/bochs.c
@@ -185,8 +185,9 @@ static int64_t seek_to_sector(BlockDriverState *bs, int64_t sector_num)
 	return -1; /* not allocated */
     }
 
-    bitmap_offset = s->data_offset + (512 * s->catalog_bitmap[extent_index] *
-	(s->extent_blocks + s->bitmap_blocks));
+    bitmap_offset = s->data_offset +
+        (512 * (uint64_t) s->catalog_bitmap[extent_index] *
+        (s->extent_blocks + s->bitmap_blocks));
 
     /* read in bitmap for current extent */
     if (bdrv_pread(bs->file, bitmap_offset + (extent_offset / 8),
-- 
1.7.1