From: Kevin Wolf <kw...@redhat.com>
Limiting the size of a single request to INT_MAX not only fixes a
direct integer overflow in bdrv_check_request() (which would only
trigger bad behaviour with ridiculously huge images, as in close to
2^64 bytes), but can also prevent overflows in all block drivers.
Signed-off-by: Kevin Wolf <kw...@redhat.com>
Reviewed-by: Max Reitz <mre...@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
(cherry picked from commit 8f4754ede56e3f9ea3fd7207f4a7c4453e59285b)
Signed-off-by: Michael Roth <mdr...@linux.vnet.ibm.com>
---
block.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/block.c b/block.c
index 68651a9..202d817 100644
--- a/block.c
+++ b/block.c
@@ -2277,6 +2277,10 @@ static int bdrv_check_byte_request(BlockDriverState *bs,
int64_t offset,
static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num,
int nb_sectors)
{
+ if (nb_sectors > INT_MAX / BDRV_SECTOR_SIZE) {
+ return -EIO;
+ }
+
return bdrv_check_byte_request(bs, sector_num * BDRV_SECTOR_SIZE,
nb_sectors * BDRV_SECTOR_SIZE);
}
--
1.9.1
