fixing infinite loop, releasing 1.7

3 files changed, 82 insertions, 18 deletions

diff --git a/ChangeLog b/ChangeLog
index 0170cd8..dffc0ca 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu Jul 12 22:26:36 CEST 2018
+        Fix potential infinite loop in mpeg extractor.
+        Releasing GNU libextractor 1.7. -CG
+
 Thu Jul 12 21:23:43 CEST 2018
         Fixing length calculation error in unzip logic reported
         by ADLab of Venustech. -CG
diff --git a/configure.ac b/configure.ac
index 3fb33b0..b909572 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,7 +1,7 @@
 # Process this file with autoconf to produce a configure script.
 #
 #  This file is part of GNU libextractor
-#  Copyright (C) 2003-2017 Christian Grothoff
+#  Copyright (C) 2003-2018 Christian Grothoff
 #
 #  GNU libextractor is free software; you can redistribute it and/or modify it under the
 #  terms of the GNU General Public License as published by the Free Software
@@ -16,7 +16,7 @@
 #
 #
 AC_PREREQ(2.61)
-AC_INIT([libextractor], [1.6], [bug-libextractor@gnu.org])
+AC_INIT([libextractor], [1.7], [bug-libextractor@gnu.org])
 AC_CONFIG_HEADERS([config.h])
 AC_CONFIG_MACRO_DIR([m4])
 AH_TOP([#define _GNU_SOURCE  1])
@@ -25,7 +25,7 @@ AC_CANONICAL_HOST
 AC_CANONICAL_SYSTEM
 
 LIB_VERSION_CURRENT=4
-LIB_VERSION_REVISION=5
+LIB_VERSION_REVISION=6
 LIB_VERSION_AGE=1
 AC_SUBST(LIB_VERSION_CURRENT)
 AC_SUBST(LIB_VERSION_REVISION)
diff --git a/src/plugins/mpeg_extractor.c b/src/plugins/mpeg_extractor.c
index c855825..627cae0 100644
--- a/src/plugins/mpeg_extractor.c
+++ b/src/plugins/mpeg_extractor.c
@@ -42,7 +42,7 @@
  *
  * @param ec extraction context provided to the plugin
  */
-void 
+void
 EXTRACTOR_mpeg_extract_method (struct EXTRACTOR_ExtractContext *ec)
 {
   mpeg2dec_t *handle;
@@ -51,10 +51,19 @@ EXTRACTOR_mpeg_extract_method (struct EXTRACTOR_ExtractContext *ec)
   ssize_t avail;
   mpeg2_state_t state;
   char format[256];
+  char lformat[256];
   char gop_format[256];
   int have_gop;
   uint64_t fsize;
   unsigned int fail_count;
+  int did_seek;
+  int fmt1;
+  int fmt2;
+  int mime;
+  int fpal;
+  int fntsc;
+  int fsecam;
+  int fmac;
 
   if (NULL == (handle = mpeg2_init ()))
     return;
@@ -63,10 +72,19 @@ EXTRACTOR_mpeg_extract_method (struct EXTRACTOR_ExtractContext *ec)
       mpeg2_close (handle);
       return;
     }
-  fsize = ec->get_size (ec->cls);  
+  fsize = ec->get_size (ec->cls);
   buf = NULL;
   have_gop = 0;
   fail_count = 0;
+  did_seek = 0;
+  fmt1 = 0;
+  fmt2 = 0;
+  mime = 0;
+  fpal = 0;
+  fntsc = 0;
+  fsecam = 0;
+  fmac = 0;
+  lformat[0] = '\0';
   while (1)
     {
       state = mpeg2_parse (handle);
@@ -86,36 +104,76 @@ EXTRACTOR_mpeg_extract_method (struct EXTRACTOR_ExtractContext *ec)
           fail_count = 0;
           format[0] = fsize;
           format[0]++;
-          ADD ("video/mpeg", EXTRACTOR_METATYPE_MIMETYPE);
-          snprintf (format, 
+          if (0 == mime)
+          {
+            mime = 1;
+            ADD ("video/mpeg", EXTRACTOR_METATYPE_MIMETYPE);
+          }
+          snprintf (format,
                     sizeof(format), "%ux%u",
                     info->sequence->width, info->sequence->height);
-          ADD (format, EXTRACTOR_METATYPE_IMAGE_DIMENSIONS);
+          if (0 != strcmp (lformat,
+                           format))
+          {
+            strcpy (lformat,
+                    format);
+            ADD (format, EXTRACTOR_METATYPE_IMAGE_DIMENSIONS);
+          }
           switch (info->sequence->flags & SEQ_VIDEO_FORMAT_UNSPECIFIED)
             {
             case SEQ_VIDEO_FORMAT_PAL:
-              ADD ("PAL", EXTRACTOR_METATYPE_BROADCAST_TELEVISION_SYSTEM);
+              if (0 == fpal)
+              {
+                fpal = 1;
+                ADD ("PAL", EXTRACTOR_METATYPE_BROADCAST_TELEVISION_SYSTEM);
+              }
               break;
             case SEQ_VIDEO_FORMAT_NTSC:
-              ADD ("NTSC", EXTRACTOR_METATYPE_BROADCAST_TELEVISION_SYSTEM);
+              if (0 == fntsc)
+              {
+                fntsc = 1;
+                ADD ("NTSC", EXTRACTOR_METATYPE_BROADCAST_TELEVISION_SYSTEM);
+              }
               break;
             case SEQ_VIDEO_FORMAT_SECAM:
-              ADD ("SECAM", EXTRACTOR_METATYPE_BROADCAST_TELEVISION_SYSTEM);
+              if (0 == fsecam)
+              {
+                fsecam = 1;
+                ADD ("SECAM", EXTRACTOR_METATYPE_BROADCAST_TELEVISION_SYSTEM);
+              }
               break;
             case SEQ_VIDEO_FORMAT_MAC:
-              ADD ("MAC", EXTRACTOR_METATYPE_BROADCAST_TELEVISION_SYSTEM);
+              if (0 == fmac)
+              {
+                fmac = 1;
+                ADD ("MAC", EXTRACTOR_METATYPE_BROADCAST_TELEVISION_SYSTEM);
+              }
               break;
             default:
               break;
             }
           if ((info->sequence->flags & SEQ_FLAG_MPEG2) > 0)
-            ADD ("MPEG2", EXTRACTOR_METATYPE_FORMAT_VERSION);
+          {
+            if (0 == fmt1)
+            {
+              fmt1 = 1;
+              ADD ("MPEG2", EXTRACTOR_METATYPE_FORMAT_VERSION);
+            }
+          }
           else
-            ADD ("MPEG1", EXTRACTOR_METATYPE_FORMAT_VERSION);
-          if ( (fsize != -1) &&
+          {
+            if (0 == fmt2)
+            {
+              fmt2 = 1;
+              ADD ("MPEG1", EXTRACTOR_METATYPE_FORMAT_VERSION);
+            }
+          }
+          if ( (0 == did_seek) &&
+               (fsize != -1) &&
                (fsize > 1024 * 256 * 2) )
             {
               /* skip to the end of the mpeg for speed */
+              did_seek = 1;
               ec->seek (ec->cls,
                         fsize - 256 * 1024,
                         SEEK_SET);
@@ -126,10 +184,12 @@ EXTRACTOR_mpeg_extract_method (struct EXTRACTOR_ExtractContext *ec)
           if ( (NULL != info->gop) &&
                (0 != info->gop->pictures) )
             {
-              snprintf (gop_format, 
+              snprintf (gop_format,
                         sizeof (gop_format),
                         "%02u:%02u:%02u (%u frames)",
-                        info->gop->hours, info->gop->minutes, info->gop->seconds,
+                        info->gop->hours,
+                        info->gop->minutes,
+                        info->gop->seconds,
                         info->gop->pictures);
               have_gop = 1;
             }
@@ -148,7 +208,7 @@ EXTRACTOR_mpeg_extract_method (struct EXTRACTOR_ExtractContext *ec)
     }
  EXIT:
   if (1 == have_gop)
-    ADD (gop_format, EXTRACTOR_METATYPE_DURATION);    
+    ADD (gop_format, EXTRACTOR_METATYPE_DURATION);
   mpeg2_close (handle);
 }