Acknowledge loop execution behavior for zero height - no validation needed #283
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This patch hardens ImageBuffer and the PFM loader against malformed or malicious inputs: - Switch width/height/channels from int to size_t to avoid signed overflow. - Add maxDim guard (64K) and reject images whose total pixel count exceeds int limits to prevent integer multiplication overflow. - Validate pixel reads during PFM parsing and fail early on read errors. - Use overflow-safe width*height*C checks before allocating the buffer. - Add static_assert ensuring size_t is 64-bit on supported platforms. These changes prevent tiny allocations followed by large writes caused by untrusted PFM headers (e.g., malicious W/H/C), removing the possibility of heap-based out-of-bounds writes.
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[WIP] Fix handling loop execution for zero height in image loaders
Acknowledge loop execution behavior for zero height - no validation needed
Nov 25, 2025
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Addressed review feedback on PR #280 regarding potential underflow in
H-1-hexpression when H=0.Analysis
The bot's concern about underflow was incorrect. When H=0, the loop condition
for (size_t h = 0; h < H; ++h)evaluates to0 < 0(false), preventing loop body execution. The expressionH-1-his never evaluated, so no underflow can occur.Conclusion
No code changes required. The existing implementation correctly handles zero dimensions through the loop guard itself.
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