fix(filesystem): overflow-safe bounds check in IOMemReader::pread#5262
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IOMemReader::pread guarded its memcpy with `size + size_t(offset) > m_buf.size()`. For a large or negative offset, that addition wraps around size_t and can compare as in-bounds, skipping both the error path and the size clamp, so the memcpy reads past (or before) the buffer. Assisted-by: Claude Code / Claude Opus 4.8 Signed-off-by: Larry Gritz <lg@larrygritz.com>
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Jun 29, 2026
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IOMemReader::pread guarded its memcpy with
size + size_t(offset) > m_buf.size(). For a large or negative offset, that addition wraps around size_t and can compare as in-bounds, skipping both the error path and the size clamp, so the memcpy reads past (or before) the buffer.Assisted-by: Claude Code / Claude Opus 4.8