Remove instances of calling marshal functions with NULL pointer.

In the code scraped from the TCG TPM2.0 Library specification, there
are several instances where the intent is to marshal data into a buffer,
but NULL pointer is passed in as size.

Part 4 section 4.2.3.1 states: "If size is a NULL pointer, then no
data is marshaled and the routine will compute the size of the memory
required to marshal the indicated type."

Implying these usages are bugs. This CL removes all instances of passing
in NULL as size to a Marshal function when the intent is to marshal data.

TEST=$ sudo emerge tpm2
     builds libtpm2.a. Currently this is the only test we have for the
     scraped code.
BUG=none

Change-Id: If7b2a60f6a8e875b4a6eceab513dc22325bf4999
Reviewed-on: https://chromium-review.googlesource.com/289647
Reviewed-by: Utkarsh Sanghi <usanghi@chromium.org>
Commit-Queue: Jocelyn Bohr <bohr@chromium.org>
Tested-by: Jocelyn Bohr <bohr@chromium.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/Object.c b/Object.c
index b25de0c..5a16f8c 100644
--- a/Object.c
+++ b/Object.c
@@ -722,6 +722,7 @@ ObjectComputeName(
 {
    TPM2B_PUBLIC               marshalBuffer;
    BYTE                      *buffer;               // auxiliary marshal buffer pointer
+   INT32                      bufferSize;
    HASH_STATE                 hashState;            // hash state
    // if the nameAlg is NULL then there is no name.
    if(publicArea->nameAlg == TPM_ALG_NULL)
@@ -733,7 +734,8 @@ ObjectComputeName(
    name->t.size = CryptStartHash(publicArea->nameAlg, &hashState);
    // Marshal the public area into its canonical form
    buffer = marshalBuffer.b.buffer;
-   marshalBuffer.t.size = TPMT_PUBLIC_Marshal(publicArea, &buffer, NULL);
+   bufferSize = marshalBuffer.b.size;
+   marshalBuffer.t.size = TPMT_PUBLIC_Marshal(publicArea, &buffer, &bufferSize);
    // Adding public area
    CryptUpdateDigest2B(&hashState, &marshalBuffer.b);
    // Complete hash leaving room for the name algorithm