[vlc-commits] demux: asf: check data object range when reading

[Francois Cartegnie]

vlc | branch: master | Francois Cartegnie <fcvlcdev at free.fr> | Wed Nov  4 10:10:47 2020 +0100| [a4ed34d704ec8721b7d74542324f39c9f2aff508] | committer: Francois Cartegnie

demux: asf: check data object range when reading

> http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=a4ed34d704ec8721b7d74542324f39c9f2aff508
---

 modules/demux/asf/asf.c       |  3 ++-
 modules/demux/asf/asfpacket.c | 17 ++++++++++++++++-
 modules/demux/asf/asfpacket.h |  2 +-
 modules/demux/mp4/mp4.c       |  3 ++-
 4 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/modules/demux/asf/asf.c b/modules/demux/asf/asf.c
index 4828a77804..8446510fa6 100644
--- a/modules/demux/asf/asf.c
+++ b/modules/demux/asf/asf.c
@@ -221,7 +221,8 @@ static int Demux( demux_t *p_demux )
         /* Read and demux a packet */
         if( DemuxASFPacket( &p_sys->packet_sys,
                              p_sys->p_fp->i_min_data_packet_size,
-                             p_sys->p_fp->i_max_data_packet_size ) <= 0 )
+                             p_sys->p_fp->i_max_data_packet_size,
+                             p_sys->i_data_begin, p_sys->i_data_end ) <= 0 )
         {
             p_sys->b_eos = true;
             /* Check if we have concatenated files */
diff --git a/modules/demux/asf/asfpacket.c b/modules/demux/asf/asfpacket.c
index 0b447352df..1a94dcf0b1 100644
--- a/modules/demux/asf/asfpacket.c
+++ b/modules/demux/asf/asfpacket.c
@@ -380,10 +380,17 @@ skip:
 }
 
 int DemuxASFPacket( asf_packet_sys_t *p_packetsys,
-                 uint32_t i_data_packet_min, uint32_t i_data_packet_max )
+                    uint32_t i_data_packet_min, uint32_t i_data_packet_max,
+                    uint64_t i_data_begin, uint64_t i_data_end )
 {
     demux_t *p_demux = p_packetsys->p_demux;
 
+    const uint64_t i_read_pos = vlc_stream_Tell( p_demux->s );
+    if( i_read_pos < i_data_begin ||
+        i_data_packet_min > i_data_end ||
+        i_read_pos > i_data_end - i_data_packet_min )
+        return 0;
+
     const uint8_t *p_peek;
     ssize_t i_return = vlc_stream_Peek( p_demux->s, &p_peek,i_data_packet_min );
     if( i_return <= 0 || (size_t) i_return < i_data_packet_min )
@@ -452,6 +459,14 @@ int DemuxASFPacket( asf_packet_sys_t *p_packetsys,
     pkt.send_time = VLC_TICK_FROM_MS(GetDWLE( p_peek + i_skip )); i_skip += 4;
     /* uint16_t i_packet_duration = GetWLE( p_peek + i_skip ); */ i_skip += 2;
 
+    if( pkt.length > i_data_end ||
+        i_read_pos > i_data_end - pkt.length )
+    {
+        msg_Warn( p_demux, "pkt size %"PRIu32" at %"PRIu64" does not fit data chunk",
+                  pkt.length, i_read_pos );
+        return 0;
+    }
+
     i_return = vlc_stream_Peek( p_demux->s, &p_peek, pkt.length );
     if( i_return <= 0 || pkt.length == 0 || (size_t)i_return < pkt.length )
     {
diff --git a/modules/demux/asf/asfpacket.h b/modules/demux/asf/asfpacket.h
index 9a5af1aa66..ba11d7f56d 100644
--- a/modules/demux/asf/asfpacket.h
+++ b/modules/demux/asf/asfpacket.h
@@ -57,5 +57,5 @@ struct asf_packet_sys_s
     void (*pf_setaspectratio)(asf_packet_sys_t *, uint8_t, uint8_t, uint8_t);
 };
 
-int DemuxASFPacket( asf_packet_sys_t *, uint32_t, uint32_t );
+int DemuxASFPacket( asf_packet_sys_t *, uint32_t, uint32_t, uint64_t, uint64_t );
 #endif
diff --git a/modules/demux/mp4/mp4.c b/modules/demux/mp4/mp4.c
index 875d8c4d38..152441750d 100644
--- a/modules/demux/mp4/mp4.c
+++ b/modules/demux/mp4/mp4.c
@@ -719,7 +719,8 @@ static void MP4_Block_Send( demux_t *p_demux, mp4_track_t *p_track, block_t *p_b
             p_track->i_dts_backup = p_block->i_dts;
             p_track->i_pts_backup = p_block->i_pts;
             /* And demux it as ASF packet */
-            DemuxASFPacket( &p_sys->asfpacketsys, p_block->i_buffer, p_block->i_buffer );
+            DemuxASFPacket( &p_sys->asfpacketsys, p_block->i_buffer, p_block->i_buffer,
+                            0, p_block->i_buffer );
             vlc_stream_Delete(p_demux->s);
         }
         block_Release(p_block);