commit 81b452d245c19e9a16681567b9dbcf0f7a71ac78 Author: Mansour Moufid mansourmoufid@gmail.com Date: Sun Oct 19 13:12:11 2014 -0400

Document the calloc function overflow check. --- src/common/util.c | 4 ++++ 1 file changed, 4 insertions(+)

diff --git a/src/common/util.c b/src/common/util.c index 013a501..74a538e 100644 --- a/src/common/util.c +++ b/src/common/util.c @@ -195,8 +195,10 @@ tor_malloc_zero_(size_t size DMALLOC_PARAMS) return result; }

+/* Estimate the square root of SIZE_MAX. */ #define SQRT_SIZE_MAX (((size_t) SIZE_MAX) >> (sizeof(size_t) * 8 / 2))

+/** Return non-zero if and only if the product of the arguments is exact. */ static INLINE int size_mul_check(const size_t x, const size_t y) { @@ -208,6 +210,8 @@ size_mul_check(const size_t x, const size_t y) * the memory with zero bytes, and return a pointer to the result. * Log and terminate the process on error. (Same as * calloc(<b>nmemb</b>,<b>size</b>), but never returns NULL.) + * The second argument (<b>size</b>) should preferably be non-zero + * and a compile-time constant. */ void * tor_calloc_(size_t nmemb, size_t size DMALLOC_PARAMS)