wav: fix integer overflow (CVE-2008-2430)

[vlc] / modules / demux / wav.c

diff --git a/modules/demux/wav.c b/modules/demux/wav.c
index 0613dd868d4dd8a485f463d051a16614fe0566c0..045344a08e25ddd2e6a934c5429b208c5b101b73 100644 (file)
--- a/modules/demux/wav.c
+++ b/modules/demux/wav.c
@@ -1,7 +1,7 @@
 /*****************************************************************************
  * wav.c : wav file input module for vlc
  *****************************************************************************
- * Copyright (C) 2001-2007 the VideoLAN team
+ * Copyright (C) 2001-2008 the VideoLAN team
  * $Id$
  *
  * Authors: Laurent Aimar <fenrir@via.ecp.fr>
@@ -106,7 +106,8 @@ static int Open( vlc_object_t * p_this )
     demux_sys_t *p_sys;
 
     const uint8_t *p_peek;
-    unsigned int i_size, i_extended;
+    uint32_t     i_size;
+    unsigned int i_extended;
     const char        *psz_name;
 
     WAVEFORMATEXTENSIBLE *p_wf_ext = NULL;
@@ -139,7 +140,8 @@ static int Open( vlc_object_t * p_this )
         msg_Err( p_demux, "cannot find 'fmt ' chunk" );
         goto error;
     }
-    if( i_size < sizeof( WAVEFORMATEX ) - 2 )   /* XXX -2 isn't a typo */
+    i_size += 2;
+    if( i_size < sizeof( WAVEFORMATEX ) )
     {
         msg_Err( p_demux, "invalid 'fmt ' chunk" );
         goto error;
@@ -147,14 +149,15 @@ static int Open( vlc_object_t * p_this )
     stream_Read( p_demux->s, NULL, 8 );   /* Cannot fail */
 
     /* load waveformatex */
-    p_wf_ext = malloc( __EVEN( i_size ) + 2 );
+    p_wf_ext = malloc( i_size );
     if( p_wf_ext == NULL )
          goto error;
 
     p_wf = (WAVEFORMATEX *)p_wf_ext;
     p_wf->cbSize = 0;
-    if( stream_Read( p_demux->s,
-                     p_wf, __EVEN( i_size ) ) < (int)__EVEN( i_size ) )
+    i_size -= 2;
+    if( stream_Read( p_demux->s, p_wf, i_size ) != (int)i_size
+     || ( ( i_size & 1 ) && stream_Read( p_demux->s, NULL, 1 ) != 1 ) )
     {
         msg_Err( p_demux, "cannot load 'fmt ' chunk" );
         goto error;
@@ -382,17 +385,17 @@ static int ChunkFind( demux_t *p_demux, const char *fcc, unsigned int *pi_size )
 
     for( ;; )
     {
-        int i_size;
+        uint32_t i_size;
 
         if( stream_Peek( p_demux->s, &p_peek, 8 ) < 8 )
         {
-            msg_Err( p_demux, "cannot peek()" );
+            msg_Err( p_demux, "cannot peek" );
             return VLC_EGENERIC;
         }
 
         i_size = GetDWLE( p_peek + 4 );
 
-        msg_Dbg( p_demux, "chunk: fcc=`%4.4s` size=%d", p_peek, i_size );
+        msg_Dbg( p_demux, "chunk: fcc=`%4.4s` size=%"PRIu32, p_peek, i_size );
 
         if( !memcmp( p_peek, fcc, 4 ) )
         {
@@ -403,11 +406,11 @@ static int ChunkFind( demux_t *p_demux, const char *fcc, unsigned int *pi_size )
             return VLC_SUCCESS;
         }
 
-        i_size = __EVEN( i_size ) + 8;
-        if( stream_Read( p_demux->s, NULL, i_size ) != i_size )
-        {
+        /* Skip chunk */
+        if( stream_Read( p_demux->s, NULL, 8 ) != 8
+         || stream_Read( p_demux->s, NULL, i_size ) != i_size
+         || ((i_size & 1) && stream_Read( p_demux->s, NULL, 1 ) != 1 ))
             return VLC_EGENERIC;
-        }
     }
 }