Fix preamble range checks

firmware/lib/vboot_common.c

Index: firmware/lib/vboot_common.c
diff --git a/firmware/lib/vboot_common.c b/firmware/lib/vboot_common.c
index d9838c41fcca8c2a0061fa3d55d6ce5d312e1bd6..a20e16fb0a808a1ddc267d0b63c7ac27cc3cf838 100644
--- a/firmware/lib/vboot_common.c
+++ b/firmware/lib/vboot_common.c
@@ -333,15 +333,15 @@ int VerifyFirmwarePreamble(const VbFirmwarePreambleHeader* preamble,
     return VBOOT_PREAMBLE_INVALID;
   }
 
-  /* Verify body signature is inside the block */
-  if (VerifySignatureInside(preamble, preamble->preamble_size,
+  /* Verify body signature is inside the signed data */
+  if (VerifySignatureInside(preamble, sig->data_size,
                             &preamble->body_signature)) {
     VBDEBUG(("Firmware body signature off end of preamble\n"));
     return VBOOT_PREAMBLE_INVALID;
   }
 
-  /* Verify kernel subkey is inside the block */
-  if (VerifyPublicKeyInside(preamble, preamble->preamble_size,
+  /* Verify kernel subkey is inside the signed data */
+  if (VerifyPublicKeyInside(preamble, sig->data_size,
                             &preamble->kernel_subkey)) {
     VBDEBUG(("Kernel subkey off end of preamble\n"));
     return VBOOT_PREAMBLE_INVALID;
@@ -387,8 +387,8 @@ int VerifyKernelPreamble(const VbKernelPreambleHeader* preamble,
     return VBOOT_PREAMBLE_INVALID;
   }
 
-  /* Verify body signature is inside the block */
-  if (VerifySignatureInside(preamble, preamble->preamble_size,
+  /* Verify body signature is inside the signed data */
+  if (VerifySignatureInside(preamble, sig->data_size,
                             &preamble->body_signature)) {
     VBDEBUG(("Kernel body signature off end of preamble\n"));
     return VBOOT_PREAMBLE_INVALID;