fix(appsec): off by one#3506
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Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## master #3506 +/- ##
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- Coverage 61.83% 61.69% -0.14%
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Files 142 142
Lines 12923 12923
Branches 1695 1695
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- Hits 7991 7973 -18
- Misses 4178 4196 +18
Partials 754 754
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Anilm3
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Nov 28, 2025
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Description
sizeof("1")returns2because it includes the terminating\0, whilesprintf()always also writes the terminating\0. So if we do this (decrementing the return ofsizeof("string"):dd-trace-php/appsec/src/extension/request_abort.c
Lines 518 to 519 in 0c35caf
... then there is an off by one, as the
bufis "only" 20 bytes, whilesprintf()might actually write 21 bytes to that pointer if the number inbody_lenneeds 20 digits in a string. Additionally switching tosnprintf()makes sure we never overflow.Granted: this number overflowing seems highly unlikely, but theoretically still possible.
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