[vlc-commits] asf: Fix out of bound read

[Hugo Beauzée-Luyssen]

vlc | branch: master | Hugo Beauzée-Luyssen <hugo at beauzee.fr> | Wed Aug  7 17:36:37 2019 +0200| [fdbdd677c1e6262f31771b0ba10afb24aabf108c] | committer: Hugo Beauzée-Luyssen

asf: Fix out of bound read

p_data is already offset by 64 bytes, so we need to propagate that
offset to the boundary check

CVE-2019-14776

> http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=fdbdd677c1e6262f31771b0ba10afb24aabf108c
---

 modules/demux/asf/asf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modules/demux/asf/asf.c b/modules/demux/asf/asf.c
index 9dd30eb462..441d9ec7e4 100644
--- a/modules/demux/asf/asf.c
+++ b/modules/demux/asf/asf.c
@@ -1105,7 +1105,7 @@ static int DemuxInit( demux_t *p_demux )
                 {
                     GET_CHECKED( fmt.i_extra, __MIN( GetWLE( &p_data[16] ),
                                          p_sp->i_type_specific_data_length -
-                                         sizeof( WAVEFORMATEX ) ),
+                                         sizeof( WAVEFORMATEX ) - 64),
                                  INT_MAX, uint32_t );
                     fmt.p_extra = malloc( fmt.i_extra );
                     if ( fmt.p_extra )