YaHTTP: Prevent integer overflow on very large chunks #12892
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If the chunk_size is very close to the maximum value of an integer, we trigger an integer overflow when checking if we have a trailing newline after the payload. Reported by OSS-Fuzz as: https://oss-fuzz.com/testcase-detail/6439610474692608 https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=56804
fredmorcos
approved these changes
Jun 13, 2023
| @@ -177,6 +179,9 @@ namespace YaHTTP { | |||
| throw ParseError("Unable to parse chunk size"); | |||
| } | |||
| if (chunk_size == 0) { state = 3; break; } // last chunk | |||
| if (chunk_size > (std::numeric_limits<decltype(chunk_size)>::max() - 2)) { | |||
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- 2 for a potential \r\n? Perhaps a comment would help here.
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Agreed, and since we try to keep this code in sync with the upstream repository if we want to make that change we should open a PR there :)
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This was referenced Jul 26, 2023
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Short description
If the chunk_size is very close to the maximum value of an integer, we trigger an integer overflow when checking if we have a trailing newline after the payload.
Reported by OSS-Fuzz as:
Upstream request at cmouse/yahttp#28
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