Since a too small file cannot be a valid VMDK image, and also since the
buffer's first 4 bytes will be unconditionally examined by
vmdk_open_sparse, let's error out the small file case to be clear.
Signed-off-by: Fam Zheng <f...@redhat.com>
---
block/vmdk.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/block/vmdk.c b/block/vmdk.c
index 5f43226..b703395 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -557,6 +557,14 @@ static char *vmdk_read_desc(BlockDriverState *file,
uint64_t desc_offset,
return NULL;
}
+ if (size < 4) {
+ /* Both descriptor file and sparse image must be much larger than 4
+ * bytes, also callers of vmdk_read_desc want to compare the first 4
+ * bytes with VMDK4_MAGIC, let's error out if less is read. */
+ error_setg(errp, "File is too small, not a valid image");
+ return NULL;
+ }
+
size = MIN(size, (1 << 20) - 1); /* avoid unbounded allocation */
buf = g_malloc(size + 1);
--
1.9.3
