Cast between HRESULT and a Boolean type¶
ID: cpp/hresult-boolean-conversion
Kind: problem
Severity: error
Precision: high
Tags:
- security
- external/cwe/cwe-253
- external/microsoft/C6214
- external/microsoft/C6215
- external/microsoft/C6216
- external/microsoft/C6217
- external/microsoft/C6230
Query suites:
- cpp-code-scanning.qls
- cpp-security-extended.qls
- cpp-security-and-quality.qls
Click to see the query in the CodeQL repository
This query indicates that an HRESULT is being cast to a Boolean type or vice versa.
The typical success value (S_OK) of an HRESULT equals 0. However, 0 indicates failure for a Boolean type.
Casting an HRESULT to a Boolean type and then using it in a test expression will yield an incorrect result.
Recommendation¶
To check if a call that returns an HRESULT succeeded use the FAILED macro.
Example¶
In the following example, HRESULT is used in a test expression incorrectly as it may yield an incorrect result.
LPMALLOC pMalloc;
HRESULT hr = CoGetMalloc(1, &pMalloc);
if (!hr)
{
// code ...
}
To fix this issue, use the FAILED macro in the test expression.