Made GetExecOutput() return an empty string on empty command output#6226
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aleksandrychev merged 1 commit intoJul 9, 2026
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The read loop never touched the output buffer when the command produced no output: it hit EOF on the first iteration and returned success, leaving the buffer exactly as the caller allocated it. A caller using malloc() then saw stale heap data as command output — this made cf-agent's container inventory intermittently treat a freed 'docker image inspect' JSON buffer as the 'docker volume ls --quiet' result on Windows. NUL-terminate the buffer up front so callers always get a valid, possibly empty, string. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Signed-off-by: Ihor Aleksandrychiev <ihor.aleksandrychiev@northern.tech>
craigcomstock
approved these changes
Jul 9, 2026
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The read loop never touched the output buffer when the command produced no output: it hit EOF on the first iteration and returned success, leaving the buffer exactly as the caller allocated it. A caller using malloc() then saw stale heap data as command output — this made cf-agent's container inventory intermittently treat a freed 'docker image inspect' JSON buffer as the 'docker volume ls --quiet' result on Windows.
NUL-terminate the buffer up front so callers always get a valid, possibly empty, string.