tor-browser

dav1d_fuzzer.c (5887B)

---

/*
* Copyright © 2018, VideoLAN and dav1d authors
* Copyright © 2018, Janne Grunau
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
*    list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
*    this list of conditions and the following disclaimer in the documentation
*    and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#include "config.h"

#include <errno.h>
#include <stddef.h>
#include <stdint.h>
#include <string.h>
#include <stdlib.h>

#include <dav1d/dav1d.h>
#include "src/cpu.h"
#include "dav1d_fuzzer.h"

#ifdef DAV1D_ALLOC_FAIL

#include "alloc_fail.h"

static unsigned djb_xor(const uint8_t * c, size_t len) {
   unsigned hash = 5381;
   for(size_t i = 0; i < len; i++)
       hash = hash * 33 ^ c[i];
   return hash;
}
#endif

static unsigned r32le(const uint8_t *const p) {
   return ((uint32_t)p[3] << 24U) | (p[2] << 16U) | (p[1] << 8U) | p[0];
}

#define DAV1D_FUZZ_MAX_SIZE 4096 * 4096

// search for "--cpumask xxx" in argv and remove both parameters
int LLVMFuzzerInitialize(int *argc, char ***argv) {
   int i = 1;
   for (; i < *argc; i++) {
       if (!strcmp((*argv)[i], "--cpumask")) {
           const char * cpumask = (*argv)[i+1];
           if (cpumask) {
               char *end;
               unsigned res;
               if (!strncmp(cpumask, "0x", 2)) {
                   cpumask += 2;
                   res = (unsigned) strtoul(cpumask, &end, 16);
               } else {
                   res = (unsigned) strtoul(cpumask, &end, 0);
               }
               if (end != cpumask && !end[0]) {
                   dav1d_set_cpu_flags_mask(res);
               }
           }
           break;
       }
   }

   for (; i < *argc - 2; i++) {
       (*argv)[i] = (*argv)[i + 2];
   }

   *argc = i;

   return 0;
}


// expects ivf input

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
{
   Dav1dSettings settings = { 0 };
   Dav1dContext * ctx = NULL;
   Dav1dPicture pic;
   const uint8_t *ptr = data;
   int have_seq_hdr = 0;
   int err;

   dav1d_version();

   if (size < 32) goto end;
#ifdef DAV1D_ALLOC_FAIL
   unsigned h = djb_xor(ptr, 32);
   unsigned seed = h;
   unsigned probability = h > (RAND_MAX >> 5) ? RAND_MAX >> 5 : h;
   int max_frame_delay = (h & 0xf) + 1;
   int n_threads = ((h >> 4) & 0x7) + 1;
   if (max_frame_delay > 5) max_frame_delay = 1;
   if (n_threads > 3) n_threads = 1;
#endif
   ptr += 32; // skip ivf header

   dav1d_default_settings(&settings);

#ifdef DAV1D_MT_FUZZING
   settings.max_frame_delay = settings.n_threads = 4;
#elif defined(DAV1D_ALLOC_FAIL)
   settings.max_frame_delay = max_frame_delay;
   settings.n_threads = n_threads;
   dav1d_setup_alloc_fail(seed, probability);
#else
   settings.max_frame_delay = settings.n_threads = 1;
#endif
#if defined(DAV1D_FUZZ_MAX_SIZE)
   settings.frame_size_limit = DAV1D_FUZZ_MAX_SIZE;
#endif

   err = dav1d_open(&ctx, &settings);
   if (err < 0) goto end;

   while (ptr <= data + size - 12) {
       Dav1dData buf;
       uint8_t *p;

       size_t frame_size = r32le(ptr);
       ptr += 12;

       if (frame_size > size || ptr > data + size - frame_size)
           break;

       if (!frame_size) continue;

       if (!have_seq_hdr) {
           Dav1dSequenceHeader seq;
           int err = dav1d_parse_sequence_header(&seq, ptr, frame_size);
           // skip frames until we see a sequence header
           if  (err != 0) {
               ptr += frame_size;
               continue;
           }
           have_seq_hdr = 1;
       }

       // copy frame data to a new buffer to catch reads past the end of input
       p = dav1d_data_create(&buf, frame_size);
       if (!p) goto cleanup;
       memcpy(p, ptr, frame_size);
       ptr += frame_size;

       do {
           if ((err = dav1d_send_data(ctx, &buf)) < 0) {
               if (err != DAV1D_ERR(EAGAIN))
                   break;
           }
           memset(&pic, 0, sizeof(pic));
           err = dav1d_get_picture(ctx, &pic);
           if (err == 0) {
               dav1d_picture_unref(&pic);
           } else if (err != DAV1D_ERR(EAGAIN)) {
               break;
           }
       } while (buf.sz > 0);

       if (buf.sz > 0)
           dav1d_data_unref(&buf);
   }

   memset(&pic, 0, sizeof(pic));
   if ((err = dav1d_get_picture(ctx, &pic)) == 0) {
       /* Test calling dav1d_picture_unref() after dav1d_close() */
       do {
           Dav1dPicture pic2 = { 0 };
           if ((err = dav1d_get_picture(ctx, &pic2)) == 0)
               dav1d_picture_unref(&pic2);
       } while (err != DAV1D_ERR(EAGAIN));

       dav1d_close(&ctx);
       dav1d_picture_unref(&pic);
       return 0;
   }

cleanup:
   dav1d_close(&ctx);
end:
   return 0;
}