[Tboot-changelog] changeset in code: Fix crash when TPM is missing

[Gang W. <gan...@in...>]

changeset 687048b24ef3 in /hg/p/tboot/code
details: http://hg.code.sf.net/p/tboot/code/code?cmd=changeset;node=687048b24ef3
description:
	Fix crash when TPM is missing

	The latest tboot crashes during boot if there's no TPM at all, because
	write_tb_error_code() tries to dereference the null g_tpm pointer.

	IMHO all the functions that dereference g_tpm should first check if
	it's null, and return an error code. This patch fixes only one
	instance.

	Signed-off-by: Ed Swierk <es...@sk...>

diffstat:

 tboot/common/tb_error.c |  2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diffs (12 lines):

diff -r 2cb8d6ec8a4a -r 687048b24ef3 tboot/common/tb_error.c
--- a/tboot/common/tb_error.c	Mon Feb 24 11:09:06 2014 +0800
+++ b/tboot/common/tb_error.c	Mon Feb 24 11:09:18 2014 +0800
@@ -157,7 +157,7 @@
  */
 bool write_tb_error_code(tb_error_t error)
 {
-    if ( no_err_idx )
+    if ( !g_tpm || no_err_idx )
         return false;
 
     if ( !g_tpm->nv_write(g_tpm, 0, g_tpm->tb_err_index, 0,