diff options
Diffstat (limited to 'custom_mutators/honggfuzz/mangle.c')
| -rw-r--r-- | custom_mutators/honggfuzz/mangle.c | 34 |
1 files changed, 16 insertions, 18 deletions
diff --git a/custom_mutators/honggfuzz/mangle.c b/custom_mutators/honggfuzz/mangle.c index 05e0dcfa..c2988319 100644 --- a/custom_mutators/honggfuzz/mangle.c +++ b/custom_mutators/honggfuzz/mangle.c @@ -51,7 +51,7 @@ static inline size_t mangle_LenLeft(run_t *run, size_t off) { } -/* Get a random value between <1:max> with x^2 distribution */ +/* Get a random value <1:max>, but prefer smaller ones - up to 4KiB */ static inline size_t mangle_getLen(size_t max) { if (max > _HF_INPUT_MAX_SIZE) { @@ -64,27 +64,25 @@ static inline size_t mangle_getLen(size_t max) { if (max == 0) { LOG_F("max == 0"); } if (max == 1) { return 1; } - const uint64_t max2 = (uint64_t)max * max; - const uint64_t max3 = (uint64_t)max * max * max; - const uint64_t rnd = util_rndGet(1, max2 - 1); + /* Give 50% chance the the uniform distribution */ + switch (util_rndGet(0, 9)) { - uint64_t ret = rnd * rnd; - ret /= max3; - ret += 1; - - if (ret < 1) { - - LOG_F("ret (%" PRIu64 ") < 1, max:%zu, rnd:%" PRIu64, ret, max, rnd); - - } - - if (ret > max) { - - LOG_F("ret (%" PRIu64 ") > max (%zu), rnd:%" PRIu64, ret, max, rnd); + case 0: + return (size_t)util_rndGet(1, HF_MIN(16, max)); + case 1: + return (size_t)util_rndGet(1, HF_MIN(64, max)); + case 2: + return (size_t)util_rndGet(1, HF_MIN(256, max)); + case 3: + return (size_t)util_rndGet(1, HF_MIN(1024, max)); + case 4: + return (size_t)util_rndGet(1, HF_MIN(4096, max)); + default: + break; } - return (size_t)ret; + return (size_t)util_rndGet(1, max); } |