soundlib: fix CVE-2017-12839 in libmpg123

Original patch: https://www.mpg123.de/cgi-bin/scm/mpg123/trunk/src/libmpg123/getbits.h?view=patch&r1=2024&r2=4323
tyabus · Aug 18, 2022 · 8a5e21a · 8a5e21a
1 parent f246a0c
commit 8a5e21a
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/engine/common/soundlib/libmpg/getbits.h b/engine/common/soundlib/libmpg/getbits.h
@@ -55,6 +55,10 @@ static uint32_t getbits( mpg123_handle_t *fr, int number_of_bits )
 {
 	ulong	rval;
 
+	if( (long)(fr->wordpointer-fr->bsbuf)*8
+		+ fr->bitindex+number_of_bits > (long)fr->framesize*8 )
+		return 0;
+
 	rval = fr->wordpointer[0];
 	rval <<= 8;
 	rval |= fr->wordpointer[1];
@@ -73,4 +77,4 @@ static uint32_t getbits( mpg123_handle_t *fr, int number_of_bits )
 	return rval;
 }
 
-#endif//GETBITS_H
+#endif//GETBITS_H