Fix null pointer read while parsing CDX file

Author: the-blank-x

src/warc.c

@@ -1427,7 +1427,8 @@ store_warc_record (const char *uri, const char *date, const char *uuid,
    checksum and record ID fields. */
 static bool
 warc_parse_cdx_header (char *lineptr, int *field_num_original_url,
-                       int *field_num_checksum, int *field_num_record_id)
+                       int *field_num_date, int *field_num_checksum,
+                       int *field_num_record_id)
 {
   char *token;
   char *save_ptr;
@@ -1451,6 +1452,9 @@ warc_parse_cdx_header (char *lineptr, int *field_num_original_url,
                 case 'a':
                   *field_num_original_url = field_num;
                   break;
+                case 'b':
+                  *field_num_date = field_num;
+                  break;
                 case 'k':
                   *field_num_checksum = field_num;
                   break;
@@ -1464,16 +1468,19 @@ warc_parse_cdx_header (char *lineptr, int *field_num_original_url,
     }
 
   return *field_num_original_url != -1
+         && *field_num_date != -1
          && *field_num_checksum != -1
          && *field_num_record_id != -1;
 }
 
 /* Parse the CDX record and add it to the warc_dedup_table hash table. */
 static void
 warc_process_cdx_line (char *lineptr, int field_num_original_url,
-                       int field_num_checksum, int field_num_record_id)
+                       int field_num_date, int field_num_checksum,
+                       int field_num_record_id)
 {
   char *original_url = NULL;
+  char *date = NULL;
   char *checksum = NULL;
   char *record_id = NULL;
   char *token;
@@ -1487,6 +1494,8 @@ warc_process_cdx_line (char *lineptr, int field_num_original_url,
       char **val;
       if (field_num == field_num_original_url)
         val = &original_url;
+      else if (field_num == field_num_date)
+        val = &date;
       else if (field_num == field_num_checksum)
         val = &checksum;
       else if (field_num == field_num_record_id)
@@ -1501,7 +1510,10 @@ warc_process_cdx_line (char *lineptr, int field_num_original_url,
       field_num++;
     }
 
-  if (original_url != NULL && checksum != NULL && record_id != NULL)
+  if (original_url != NULL
+      && date != NULL
+      && checksum != NULL
+      && record_id != NULL)
     {
       /* For some extra efficiency, we decode the base32 encoded
          checksum value.  This should produce exactly SHA1_DIGEST_SIZE
@@ -1515,12 +1527,13 @@ warc_process_cdx_line (char *lineptr, int field_num_original_url,
       if (checksum_v != NULL && checksum_l == SHA1_DIGEST_SIZE)
         {
           /* This is a valid line with a valid checksum. */
-          store_warc_record(original_url, NULL, record_id, checksum_v);
+          store_warc_record(original_url, date, record_id, checksum_v);
           xfree (checksum_v);
         }
       else
         {
           xfree (original_url);
+          xfree (date);
           xfree (checksum_v);
           xfree (record_id);
         }
@@ -1529,6 +1542,7 @@ warc_process_cdx_line (char *lineptr, int field_num_original_url,
     {
       xfree(checksum);
       xfree(original_url);
+      xfree(date);
       xfree(record_id);
     }
 }
@@ -1543,6 +1557,7 @@ warc_load_cdx_dedup_file (void)
   size_t n = 0;
   ssize_t line_length;
   int field_num_original_url = -1;
+  int field_num_date = -1;
   int field_num_checksum = -1;
   int field_num_record_id = -1;
 
@@ -1558,7 +1573,8 @@ warc_load_cdx_dedup_file (void)
   line_length = getline (&lineptr, &n, f);
   if (line_length != -1)
     warc_parse_cdx_header (lineptr, &field_num_original_url,
-                           &field_num_checksum, &field_num_record_id);
+                           &field_num_date, &field_num_checksum,
+                           &field_num_record_id);
 
   /* If the file contains all three fields, read the complete file. */
   if (field_num_original_url == -1
@@ -1568,6 +1584,9 @@ warc_load_cdx_dedup_file (void)
       if (field_num_original_url == -1)
         logprintf (LOG_NOTQUIET,
 _("CDX file does not list original urls. (Missing column 'a'.)\n"));
+      if (field_num_date == -1)
+        logprintf (LOG_NOTQUIET,
+_("CDX file does not list dates. (Missing column 'b'.)\n"));
       if (field_num_checksum == -1)
         logprintf (LOG_NOTQUIET,
 _("CDX file does not list checksums. (Missing column 'k'.)\n"));
@@ -1587,7 +1606,8 @@ _("CDX file does not list record ids. (Missing column 'u'.)\n"));
           if (line_length != -1)
             {
               warc_process_cdx_line (lineptr, field_num_original_url,
-                            field_num_checksum, field_num_record_id);
+                            field_num_date, field_num_checksum,
+                            field_num_record_id);
             }
 
         }