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Potential fix for code scanning alert no. 3240: Multiplication result converted to larger type#134

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alert-autofix-3240
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Potential fix for code scanning alert no. 3240: Multiplication result converted to larger type#134
bniladridas wants to merge 1 commit into
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alert-autofix-3240

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Potential fix for https://github.com/bniladridas/hybrid-compute/security/code-scanning/3240

The correct fix is to force the allocation-size multiplication to be performed in size_t rather than int, so intermediate overflow cannot happen in int arithmetic.
Best single change: in include/stb_image.h at the allocation line in the PSD loader branch (around line 6902), replace stbi__malloc(4 * w * h) with stbi__malloc((size_t)4 * (size_t)w * (size_t)h) (or equivalent 4u/size_t promotion). This keeps functionality unchanged (same intended byte count), but ensures type-safe evaluation before passing to allocator. No new imports/dependencies are needed because size_t is already available via existing standard headers in this file context.

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… converted to larger type

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>
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⚠️ No Changeset found

Latest commit: 4756336

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

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@github-actions github-actions Bot added the core label May 4, 2026
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github-actions Bot commented May 4, 2026

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☑️ I checked the pre-commit hooks and there was nothing to fix at commit 4756336.

bniladridas added a commit that referenced this pull request May 4, 2026
Combines all 15 automated code scanning alert fixes for multiplication
result converted to larger type. These changes span
`include/stb_image.h`, `include/stb_image_write.h`, and
`src/preprocess.c` with consistent application of `size_t` casts to
prevent integer overflow before conversion to larger types. Overflow
checks are added where allocation sizes are stored back into `int`
variables such as `out_size`.

> [!NOTE]
> Merging this pull request will automatically close #125, #126, #127,
#128, #129, #130, #131, #132, #133, #134, #135, #136, #137, #138, #139

---------

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>
Co-authored-by: Niladri Das <bniladridas@users.noreply.github.com>
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Fixed in #140

@bniladridas bniladridas closed this May 4, 2026
@bniladridas bniladridas deleted the alert-autofix-3240 branch May 4, 2026 16:48
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