c-ares / c-ares / 28745845168

90%

Build Type

push

github

Committed by web-flow

Commit Message

Prevent integer overflow in allocation size calculations (#1147)

### Summary

Prevent potential integer overflow in allocation size calculations and
ensure safe failure behavior.

### Changes

* Add `ares_size_t_mul_overflow` helper for checked multiplication
* Introduce overflow-safe allocation helpers:

  * `ares_malloc_zero_array`
  * `ares_realloc_zero_array`
* Apply safe allocation in `ares_parse_ns_reply` (input parsing path)
* Guard against wraparound in `ares_array_set_size` during power-of-2
growth

### Behavior

* No functional changes except:

  * returning `NULL` / `ARES_ENOMEM` on overflow
* Existing allocation and initialization semantics preserved

### Scope

* Minimal and localized changes
* No API changes or refactoring
* Only affects allocation size calculations and related safety checks

---------

Signed-off-by: Syed Mohammed Nayyar <jmestwa@gmail.com>
Signed-off-by: Brad House <brad@brad-house.com>
Co-authored-by: Brad House <brad@brad-house.com>

Coverage Stats

28 of 28 new or added lines in 6 files covered. (100.0%)

1 existing line in 1 file now uncovered.

24096 of 26810 relevant lines covered (89.88%)

15725.98 hits per line