lib/fuzzing/fuzz_stable_sort_r.c

   1 /*
   2    Fuzzing for stable_sort
   3    Copyright © Catalyst IT
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 #include "includes.h"
  20 #include "fuzzing/fuzzing.h"
  21 #include "util/stable_sort.h"
  22
  23
  24 int LLVMFuzzerInitialize(int *argc, char ***argv)
  25 {
  26         return 0;
  27 }
  28
  29 /*
  30  * For a "context" we use a byte that the values are XORed with before
  31  * comparison, for a non-obvious but stable sort order.
  32  */
  33 static int cmp_int8(int8_t *a, int8_t *b, int8_t *c)
  34 {
  35         return (*a ^ *c) - (*b ^ *c);
  36 }
  37
  38
  39 #define MAX_SIZE (1024 * 1024)
  40
  41 int LLVMFuzzerTestOneInput(const uint8_t *buf, size_t len)
  42 {
  43         size_t i;
  44         int8_t buf2[MAX_SIZE];
  45         int8_t aux[MAX_SIZE];
  46         int8_t context;
  47
  48         if (len < 1 || len > MAX_SIZE) {
  49                 return 0;
  50         }
  51         context = (int8_t)buf[0];
  52         buf++;
  53         len--;
  54
  55         memcpy(buf2, buf, len);
  56
  57         stable_sort_r(buf2, aux, len, 1,
  58                       (samba_compare_with_context_fn_t)cmp_int8,
  59                       &context);
  60
  61         for (i = 1; i < len; i++) {
  62                 int c = cmp_int8(&buf2[i - 1], &buf2[i], &context);
  63                 if (c > 0) {
  64                         abort();
  65                 }
  66         }
  67
  68         return 0;
  69 }