diff options
Diffstat (limited to 'src/script')
| -rw-r--r-- | src/script/cpp_api/s_security.cpp | 26 |
1 files changed, 18 insertions, 8 deletions
diff --git a/src/script/cpp_api/s_security.cpp b/src/script/cpp_api/s_security.cpp index b915747c6..1b1f148cd 100644 --- a/src/script/cpp_api/s_security.cpp +++ b/src/script/cpp_api/s_security.cpp @@ -344,8 +344,7 @@ bool ScriptApiSecurity::checkPath(lua_State *L, const char *path, std::string str; // Transient - std::string norel_path = fs::RemoveRelativePathComponents(path); - std::string abs_path = fs::AbsolutePath(norel_path); + std::string abs_path = fs::AbsolutePath(path); if (!abs_path.empty()) { // Don't allow accessing the settings file @@ -356,18 +355,29 @@ bool ScriptApiSecurity::checkPath(lua_State *L, const char *path, // If we couldn't find the absolute path (path doesn't exist) then // try removing the last components until it works (to allow // non-existent files/folders for mkdir). - std::string cur_path = norel_path; + std::string cur_path = path; std::string removed; while (abs_path.empty() && !cur_path.empty()) { - std::string tmp_rmed; - cur_path = fs::RemoveLastPathComponent(cur_path, &tmp_rmed); - removed = tmp_rmed + (removed.empty() ? "" : DIR_DELIM + removed); + std::string component; + cur_path = fs::RemoveLastPathComponent(cur_path, &component); + if (component == "..") { + // Parent components can't be allowed or we could allow something like + // /home/user/minetest/worlds/foo/noexist/../../../../../../etc/passwd. + // If we have previous non-relative elements in the path we might be + // able to remove them so that things like worlds/foo/noexist/../auth.txt + // could be allowed, but those paths will be interpreted as nonexistent + // by the operating system anyways. + return false; + } + removed = component + (removed.empty() ? "" : DIR_DELIM + removed); abs_path = fs::AbsolutePath(cur_path); } - if (abs_path.empty()) return false; + if (abs_path.empty()) + return false; // Add the removed parts back so that you can't, eg, create a // directory in worldmods if worldmods doesn't exist. - if (!removed.empty()) abs_path += DIR_DELIM + removed; + if (!removed.empty()) + abs_path += DIR_DELIM + removed; // Get server from registry lua_rawgeti(L, LUA_REGISTRYINDEX, CUSTOM_RIDX_SCRIPTAPI); |