iso9660: validate directory record length

diff --git a/libarchive/archive_read_support_format_iso9660.c b/libarchive/archive_read_support_format_iso9660.c
index f01d37bf682e2832120dba1f6c5ca15b85429eb3..089bb7236cd17afc08fd92522ae1f733fa0497b6 100644 (file)
--- a/libarchive/archive_read_support_format_iso9660.c
+++ b/libarchive/archive_read_support_format_iso9660.c
@@ -409,7 +409,8 @@ static int  next_entry_seek(struct archive_read *, struct iso9660 *,
                    struct file_info **);
 static struct file_info *
                parse_file_info(struct archive_read *a,
-                   struct file_info *parent, const unsigned char *isodirrec);
+                   struct file_info *parent, const unsigned char *isodirrec,
+                   size_t reclen);
 static int     parse_rockridge(struct archive_read *a,
                    struct file_info *file, const unsigned char *start,
                    const unsigned char *end);
@@ -1022,7 +1023,7 @@ read_children(struct archive_read *a, struct file_info *parent)
                        if (*(p + DR_name_len_offset) == 1
                            && *(p + DR_name_offset) == '\001')
                                continue;
-                       child = parse_file_info(a, parent, p);
+                       child = parse_file_info(a, parent, p, b - p);
                        if (child == NULL) {
                                __archive_read_consume(a, skip_size);
                                return (ARCHIVE_FATAL);
@@ -1112,7 +1113,7 @@ choose_volume(struct archive_read *a, struct iso9660 *iso9660)
         */
        seenJoliet = iso9660->seenJoliet;/* Save flag. */
        iso9660->seenJoliet = 0;
-       file = parse_file_info(a, NULL, block);
+       file = parse_file_info(a, NULL, block, vd->size);
        if (file == NULL)
                return (ARCHIVE_FATAL);
        iso9660->seenJoliet = seenJoliet;
@@ -1144,7 +1145,7 @@ choose_volume(struct archive_read *a, struct iso9660 *iso9660)
                        return (ARCHIVE_FATAL);
                }
                iso9660->seenJoliet = 0;
-               file = parse_file_info(a, NULL, block);
+               file = parse_file_info(a, NULL, block, vd->size);
                if (file == NULL)
                        return (ARCHIVE_FATAL);
                iso9660->seenJoliet = seenJoliet;
@@ -1749,7 +1750,7 @@ archive_read_format_iso9660_cleanup(struct archive_read *a)
  */
 static struct file_info *
 parse_file_info(struct archive_read *a, struct file_info *parent,
-    const unsigned char *isodirrec)
+    const unsigned char *isodirrec, size_t reclen)
 {
        struct iso9660 *iso9660;
        struct file_info *file, *filep;
@@ -1763,7 +1764,11 @@ parse_file_info(struct archive_read *a, struct file_info *parent,
 
        iso9660 = (struct iso9660 *)(a->format->data);
 
-       dr_len = (size_t)isodirrec[DR_length_offset];
+       if (reclen == 0 || reclen < (dr_len = (size_t)isodirrec[DR_length_offset])) {
+               archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
+                       "Invalid directory record length");
+               return (NULL);
+       }
        name_len = (size_t)isodirrec[DR_name_len_offset];
        location = archive_le32dec(isodirrec + DR_extent_offset);
        fsize = toi(isodirrec + DR_size_offset, DR_size_size);