Avoid TOCTOU in linenoiseHistorySave #202
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Before this commit the `linenoiseHistorySave` performed `fopen(filename, ...)` and `chmod(filename, ...)` and this creates a time of use vs time of check vulnerability. I have not checked whether this can be exploited, but the fix is trivial here: we can just use `fchmod` with the opened file descriptor and this is what this commit changes :). Btw this was found with https://codeql.github.com/ and its https://codeql.github.com/codeql-query-help/cpp/cpp-toctou-race-condition/ rule when scanning a bigger project that used linenoise as a dependency.
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Before this commit the
linenoiseHistorySaveperformedfopen(filename, ...)andchmod(filename, ...)and this creates a time of use vs time of check vulnerability.I have not checked whether this can be exploited, but the fix is trivial here: we can just use
fchmodwith the opened file descriptor and this is what this commit changes :).Btw this was found with https://codeql.github.com/ and its https://codeql.github.com/codeql-query-help/cpp/cpp-toctou-race-condition/ rule when scanning a bigger project that used linenoise as a dependency.