demux: ogg: fix int overflow when parsing daala header

modules/demux/ogg.c

@@ -2765,8 +2765,7 @@ static bool Ogg_ReadDaalaHeader( logical_stream_t *p_stream,
     oggpack_buffer opb;
     uint32_t i_timebase_numerator;
     uint32_t i_timebase_denominator;
-    int keyframe_granule_shift;
-    unsigned int i_keyframe_frequency_force;
+    int i_keyframe_granule_shift;
     uint8_t i_major;
     uint8_t i_minor;
     uint8_t i_subminor;
@@ -2800,18 +2799,12 @@ static bool Ogg_ReadDaalaHeader( logical_stream_t *p_stream,
 
     oggpack_adv( &opb, 32 ); /* frame duration */
 
-    keyframe_granule_shift = oggpack_read( &opb, 8 );
-    keyframe_granule_shift = __MIN(keyframe_granule_shift, 31);
-    i_keyframe_frequency_force = 1u << keyframe_granule_shift;
-
     /* granule_shift = i_log( frequency_force -1 ) */
-    p_stream->i_granule_shift = 0;
-    i_keyframe_frequency_force--;
-    while( i_keyframe_frequency_force )
-    {
-        p_stream->i_granule_shift++;
-        i_keyframe_frequency_force >>= 1;
-    }
+    i_keyframe_granule_shift = oggpack_read( &opb, 8 );
+    if ( i_keyframe_granule_shift < 0 || i_keyframe_granule_shift > 31 )
+        return false;
+
+    p_stream->i_granule_shift = i_keyframe_granule_shift;
 
     i_version = i_major * 1000000 + i_minor * 1000 + i_subminor;
     VLC_UNUSED(i_version);