[FFmpeg-cvslog] Merge commit '90bc423212396e96a02edc1118982ab7f7766a63'

[Clément Bœsch]

ffmpeg | branch: master | Clément Bœsch <u at pkh.me> | Wed Feb  1 15:35:56 2017 +0100| [e26e6240b6700c5e8c16d0f092f1ad46805a723c] | committer: Clément Bœsch

Merge commit '90bc423212396e96a02edc1118982ab7f7766a63'

* commit '90bc423212396e96a02edc1118982ab7f7766a63':
  mov: Wrap stsc index and count compare in a separate function

The mov_stsc_index_valid() function is replaced with a macro to prevent
signdness issues (index is not always signed, and count is always
unsigned currently).

The comparison is also adjusted to reduce the risk of overflows.

Merged-by: Clément Bœsch <u at pkh.me>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=e26e6240b6700c5e8c16d0f092f1ad46805a723c
---

 libavformat/mov.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/libavformat/mov.c b/libavformat/mov.c
index da613be..6fd43a0 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -2432,12 +2432,14 @@ static int mov_read_stsc(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     return 0;
 }
 
+#define mov_stsc_index_valid(index, count) ((index) < (count) - 1)
+
 /* Compute the samples value for the stsc entry at the given index. */
 static inline int mov_get_stsc_samples(MOVStreamContext *sc, int index)
 {
     int chunk_count;
 
-    if (index < sc->stsc_count - 1)
+    if (mov_stsc_index_valid(index, sc->stsc_count))
         chunk_count = sc->stsc_data[index + 1].first - sc->stsc_data[index].first;
     else
         chunk_count = sc->chunk_count - (sc->stsc_data[index].first - 1);
@@ -3353,7 +3355,7 @@ static void mov_build_index(MOVContext *mov, AVStream *st)
         for (i = 0; i < sc->chunk_count; i++) {
             int64_t next_offset = i+1 < sc->chunk_count ? sc->chunk_offsets[i+1] : INT64_MAX;
             current_offset = sc->chunk_offsets[i];
-            while (stsc_index + 1 < sc->stsc_count &&
+            while (mov_stsc_index_valid(stsc_index, sc->stsc_count) &&
                 i + 1 == sc->stsc_data[stsc_index + 1].first)
                 stsc_index++;
 
@@ -3476,7 +3478,7 @@ static void mov_build_index(MOVContext *mov, AVStream *st)
                 count = (chunk_samples+1023) / 1024;
             }
 
-            if (i < sc->stsc_count - 1)
+            if (mov_stsc_index_valid(i, sc->stsc_count))
                 chunk_count = sc->stsc_data[i+1].first - sc->stsc_data[i].first;
             else
                 chunk_count = sc->chunk_count - (sc->stsc_data[i].first - 1);
@@ -3497,7 +3499,7 @@ static void mov_build_index(MOVContext *mov, AVStream *st)
         // populate index
         for (i = 0; i < sc->chunk_count; i++) {
             current_offset = sc->chunk_offsets[i];
-            if (stsc_index + 1 < sc->stsc_count &&
+            if (mov_stsc_index_valid(stsc_index, sc->stsc_count) &&
                 i + 1 == sc->stsc_data[stsc_index + 1].first)
                 stsc_index++;
             chunk_samples = sc->stsc_data[stsc_index].count;
@@ -6265,7 +6267,7 @@ static int mov_read_packet(AVFormatContext *s, AVPacket *pkt)
         /* Keep track of the stsc index for the given sample, then check
         * if the stsd index is different from the last used one. */
         sc->stsc_sample++;
-        if (sc->stsc_index < sc->stsc_count - 1 &&
+        if (mov_stsc_index_valid(sc->stsc_index, sc->stsc_count) &&
             mov_get_stsc_samples(sc, sc->stsc_index) == sc->stsc_sample) {
             sc->stsc_index++;
             sc->stsc_sample = 0;


======================================================================

diff --cc libavformat/mov.c
index da613be,826be02..6fd43a0
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@@ -2432,6 -1961,11 +2432,8 @@@ static int mov_read_stsc(MOVContext *c
      return 0;
  }
  
 -static inline int mov_stsc_index_valid(int index, int count)
 -{
 -    return index + 1 < count;
 -}
++#define mov_stsc_index_valid(index, count) ((index) < (count) - 1)
+ 
  /* Compute the samples value for the stsc entry at the given index. */
  static inline int mov_get_stsc_samples(MOVStreamContext *sc, int index)
  {
@@@ -3351,22 -2337,10 +3353,22 @@@ static void mov_build_index(MOVContext 
          st->index_entries_allocated_size = (st->nb_index_entries + sc->sample_count) * sizeof(*st->index_entries);
  
          for (i = 0; i < sc->chunk_count; i++) {
 +            int64_t next_offset = i+1 < sc->chunk_count ? sc->chunk_offsets[i+1] : INT64_MAX;
              current_offset = sc->chunk_offsets[i];
-             while (stsc_index + 1 < sc->stsc_count &&
+             while (mov_stsc_index_valid(stsc_index, sc->stsc_count) &&
                  i + 1 == sc->stsc_data[stsc_index + 1].first)
                  stsc_index++;
 +
 +            if (next_offset > current_offset && sc->sample_size>0 && sc->sample_size < sc->stsz_sample_size &&
 +                sc->stsc_data[stsc_index].count * (int64_t)sc->stsz_sample_size > next_offset - current_offset) {
 +                av_log(mov->fc, AV_LOG_WARNING, "STSZ sample size %d invalid (too large), ignoring\n", sc->stsz_sample_size);
 +                sc->stsz_sample_size = sc->sample_size;
 +            }
 +            if (sc->stsz_sample_size>0 && sc->stsz_sample_size < sc->sample_size) {
 +                av_log(mov->fc, AV_LOG_WARNING, "STSZ sample size %d invalid (too small), ignoring\n", sc->stsz_sample_size);
 +                sc->stsz_sample_size = sc->sample_size;
 +            }
 +
              for (j = 0; j < sc->stsc_data[stsc_index].count; j++) {
                  int keyframe = 0;
                  if (current_sample >= sc->sample_count) {