LBA48 support (Jens Axboe)

[qemu] / block-cow.c

diff --git a/block-cow.c b/block-cow.c
index 15270df..eeeab70 100644 (file)
--- a/block-cow.c
+++ b/block-cow.c
@@ -54,7 +54,8 @@ static int cow_probe(const uint8_t *buf, int buf_size, const char *filename)
 {
     const struct cow_header_v2 *cow_header = (const void *)buf;
 
-    if (be32_to_cpu(cow_header->magic) == COW_MAGIC &&
+    if (buf_size >= sizeof(struct cow_header_v2) &&
+        be32_to_cpu(cow_header->magic) == COW_MAGIC &&
         be32_to_cpu(cow_header->version) == COW_VERSION) 
         return 100;
     else