fix potential uint overflow #243

katat · 2024-12-11T09:56:04Z

fixes #242

mimoo · 2024-12-11T17:30:07Z

src/stdlib/native/int/lib.no

@@ -14,7 +14,8 @@ struct Uint8 {
 fn Uint8.new(val: Field) -> Uint8 {
    let bit_len = 8;

-    bits::check_field_size(bit_len);
+    // has to ensure multiply won't overflow prime field
+    bits::check_field_size(bit_len * 2);


isn't it off by one?

Inside check_field_size, it checks the prime field is strictly greater than bit_len * 2:

if to_cmp >= bit_len { return Err(Error::new( "constraint-generation", ErrorKind::AssertionFailed, span, )); }

So the prime field bit len is ensured to have at least one more bit than the test value.

fix potential uint overflow

eb046e6

mimoo reviewed Dec 11, 2024

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fix potential uint overflow #243

fix potential uint overflow #243

katat commented Dec 11, 2024

mimoo Dec 11, 2024

katat Dec 12, 2024

fix potential uint overflow #243

Are you sure you want to change the base?

fix potential uint overflow #243

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katat commented Dec 11, 2024

mimoo Dec 11, 2024

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katat Dec 12, 2024

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