swtpm: Return TPM_FAIL if SWTPM_NVRAM_DecrytpData is called without key
Return TPM_FAIL if SWTPM_NVRAM_DecryptData() is called without a key or
if an unhandle type of encryption mode is encountered. Previously this
function would return no error but also would not do any decryption if
no key was provided. Consequently, it would then also not return a byte
array with decrypted data which in turn could led to potential NULL
pointer accesses in subsequent calls. However, all current callers check
whether they have a valid key before they call this function. So the
change is primarily done for static analyzers, such as gcc -fanalyzer,
to ease code analysis.
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
1 file changed
