bochs: Use unsigned variables for offsets and sizes (CVE-2014-0147)

Gets us rid of integer overflows resulting in negative sizes which
aren't correctly checked.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

diff --git a/block/bochs.c b/block/bochs.c
index d7078c0775c184e638202af4c79f76b34fb44fb0..69817650c61acba8d5e414276205ab126c754080 100644 (file)
--- a/block/bochs.c
+++ b/block/bochs.c
@@ -82,13 +82,13 @@ struct bochs_header {
 typedef struct BDRVBochsState {
     CoMutex lock;
     uint32_t *catalog_bitmap;
-    int catalog_size;
+    uint32_t catalog_size;
 
-    int data_offset;
+    uint32_t data_offset;
 
-    int bitmap_blocks;
-    int extent_blocks;
-    int extent_size;
+    uint32_t bitmap_blocks;
+    uint32_t extent_blocks;
+    uint32_t extent_size;
 } BDRVBochsState;
 
 static int bochs_probe(const uint8_t *buf, int buf_size, const char *filename)
@@ -111,7 +111,7 @@ static int bochs_probe(const uint8_t *buf, int buf_size, const char *filename)
 static int bochs_open(BlockDriverState *bs, QDict *options, int flags)
 {
     BDRVBochsState *s = bs->opaque;
-    int i;
+    uint32_t i;
     struct bochs_header bochs;
     struct bochs_header_v1 header_v1;
     int ret;
@@ -168,8 +168,8 @@ fail:
 static int64_t seek_to_sector(BlockDriverState *bs, int64_t sector_num)
 {
     BDRVBochsState *s = bs->opaque;
-    int64_t offset = sector_num * 512;
-    int64_t extent_index, extent_offset, bitmap_offset;
+    uint64_t offset = sector_num * 512;
+    uint64_t extent_index, extent_offset, bitmap_offset;
     char bitmap_entry;
 
     // seek to sector