dd: harden functions against directory traversal issues

Test correctness of all accessed dump dir files in all dd* functions.
Before this commit, the callers were allowed to pass strings like
"../../etc/shadow" in the filename argument of all dd* functions.

Related: #1214457

Signed-off-by: Jakub Filak <jfilak@redhat.com>

src/lib/create_dump_dir.c

@@ -42,6 +42,12 @@ struct dump_dir *create_dump_dir_from_problem_data(problem_data_t *problem_data,
         return NULL;
     }
 
+    if (!str_is_correct_filename(type))
+    {
+        error_msg(_("'%s' is not correct file name"), FILENAME_ANALYZER);
+        return NULL;
+    }
+
     uid_t uid = (uid_t)-1L;
     char *uid_str = problem_data_get_content_or_NULL(problem_data, FILENAME_UID);
 
@@ -105,6 +111,12 @@ struct dump_dir *create_dump_dir_from_problem_data(problem_data_t *problem_data,
     g_hash_table_iter_init(&iter, problem_data);
     while (g_hash_table_iter_next(&iter, (void**)&name, (void**)&value))
     {
+        if (!str_is_correct_filename(name))
+        {
+            error_msg("Problem data field name contains disallowed chars: '%s'", name);
+            continue;
+        }
+
         if (value->flags & CD_FLAG_BIN)
         {
             char *dest = concat_path_file(dd->dd_dirname, name);
@@ -119,13 +131,6 @@ struct dump_dir *create_dump_dir_from_problem_data(problem_data_t *problem_data,
             continue;
         }
 
-        /* only files should contain '/' and those are handled earlier */
-        if (name[0] == '.' || strchr(name, '/'))
-        {
-            error_msg("Problem data field name contains disallowed chars: '%s'", name);
-            continue;
-        }
-
         dd_save_text(dd, name, value->content);
     }
 

src/lib/dump_dir.c

@@ -345,6 +345,9 @@ static inline struct dump_dir *dd_init(void)
 
 int dd_exist(const struct dump_dir *dd, const char *path)
 {
+    if (!str_is_correct_filename(path))
+        error_msg_and_die("Cannot test existence. '%s' is not a valid file name", path);
+
     char *full_path = concat_path_file(dd->dd_dirname, path);
     int ret = exist_file_dir(full_path);
     free(full_path);
@@ -1044,6 +1047,13 @@ char* dd_load_text_ext(const struct dump_dir *dd, const char *name, unsigned fla
 //    if (!dd->locked)
 //        error_msg_and_die("dump_dir is not opened"); /* bug */
 
+    if (!str_is_correct_filename(name))
+    {
+        error_msg("Cannot load text. '%s' is not a valid file name", name);
+        if (!(flags & DD_LOAD_TEXT_RETURN_NULL_ON_FAILURE))
+            xfunc_die();
+    }
+
     /* Compat with old abrt dumps. Remove in abrt-2.1 */
     if (strcmp(name, "release") == 0)
         name = FILENAME_OS_RELEASE;
@@ -1065,6 +1075,9 @@ void dd_save_text(struct dump_dir *dd, const char *name, const char *data)
     if (!dd->locked)
         error_msg_and_die("dump_dir is not opened"); /* bug */
 
+    if (!str_is_correct_filename(name))
+        error_msg_and_die("Cannot save text. '%s' is not a valid file name", name);
+
     char *full_path = concat_path_file(dd->dd_dirname, name);
     save_binary_file(full_path, data, strlen(data), dd->dd_uid, dd->dd_gid, dd->mode);
     free(full_path);
@@ -1075,13 +1088,19 @@ void dd_save_binary(struct dump_dir* dd, const char* name, const char* data, uns
     if (!dd->locked)
         error_msg_and_die("dump_dir is not opened"); /* bug */
 
+    if (!str_is_correct_filename(name))
+        error_msg_and_die("Cannot save binary. '%s' is not a valid file name", name);
+
     char *full_path = concat_path_file(dd->dd_dirname, name);
     save_binary_file(full_path, data, size, dd->dd_uid, dd->dd_gid, dd->mode);
     free(full_path);
 }
 
 long dd_get_item_size(struct dump_dir *dd, const char *name)
 {
+    if (!str_is_correct_filename(name))
+        error_msg_and_die("Cannot get item size. '%s' is not a valid file name", name);
+
     long size = -1;
     char *iname = concat_path_file(dd->dd_dirname, name);
     struct stat statbuf;
@@ -1106,6 +1125,9 @@ int dd_delete_item(struct dump_dir *dd, const char *name)
     if (!dd->locked)
         error_msg_and_die("dump_dir is not opened"); /* bug */
 
+    if (!str_is_correct_filename(name))
+        error_msg_and_die("Cannot delete item. '%s' is not a valid file name", name);
+
     char *path = concat_path_file(dd->dd_dirname, name);
     int res = unlink(path);