diff options
| -rw-r--r-- | compiler/GHC/Runtime/Loader.hs | 48 |
1 files changed, 47 insertions, 1 deletions
diff --git a/compiler/GHC/Runtime/Loader.hs b/compiler/GHC/Runtime/Loader.hs index b59071d5f6..baf63d4dd7 100644 --- a/compiler/GHC/Runtime/Loader.hs +++ b/compiler/GHC/Runtime/Loader.hs @@ -35,6 +35,7 @@ import GHC.Runtime.Interpreter.Types import GHC.Tc.Utils.Monad ( initTcInteractive, initIfaceTcRn ) import GHC.Iface.Load ( loadPluginInterface, cannotFindModule ) +import GHC.Iface.Recomp ( addFingerprints ) import GHC.Rename.Names ( gresFromAvails ) import GHC.Builtin.Names ( pluginTyConName, frontendPluginTyConName ) @@ -156,10 +157,42 @@ checkExternalInterpreter hsc_env = case interpInstance <$> hsc_interp hsc_env of -> throwIO (InstallationError "Plugins require -fno-external-interpreter") _ -> pure () +{- +Note [Loading Plugins] +~~~~~~~~~~~~~~~~~~~~~~ + + +When loading plugins, we must be careful to check that certain packages we +depend on, like ghc the library, are ABI compatible with the packages the +plugin was linked against. + +Currently, ghc the library and the boot packages don't have an ABI hash in +their identifier. Consequently, when loading a plugin that was linked against +ghc-v-xxx into a module that is being linked against ghc-v-yyy, we must +(somehow) guarantee that xxx and yyy are indeed the same, which isn't trivial +because xxx and yyy aren't available in the package identifier. Or we risk +linking the plugin against an incompatible ghc of the same version, leading to +crashes and segmentation faults (since the loaded plugin will make use of an +incompatible library thinking it's compatible). + +A solution is to re-compute the ABI hash of the plugin being loaded and compare +it against the ABI hash of the plugin as computed by the compiler that compiled +it. If the hashes are one and the same, it's safe to load the plugin. + +-- Because the ABI hash (see addFingerprints) depends on ... ? + +See also #20742 + + +-} + loadPlugin' :: OccName -> Name -> HscEnv -> ModuleName -> IO (a, ModIface, [Linkable], PkgsLoaded) loadPlugin' occ_name plugin_name hsc_env mod_name = do { let plugin_rdr_name = mkRdrQual mod_name occ_name dflags = hsc_dflags hsc_env + + -- Find plugin_name (e.g. "plugin", "frontendPlugin") + -- in the module of the plugin to load ; mb_name <- lookupRdrNameInModuleForPlugins hsc_env mod_name plugin_rdr_name ; case mb_name of { @@ -168,8 +201,21 @@ loadPlugin' occ_name plugin_name hsc_env mod_name [ text "The module", ppr mod_name , text "did not export the plugin name" , ppr plugin_rdr_name ]) ; + -- The modiface of the plugin as compiled by possibly other compiler Just (name, mod_iface) -> + -- The modiface of the plugin as compiled by us + do { our_mod_iface <- addFingerprints hsc_env + (mod_iface{mi_final_exts = (), mi_decls = map snd (mi_decls mod_iface)}) + + -- Compare ABI hashes of module being loaded. See Note [Loading Plugins] + ; if mi_mod_hash (mi_final_exts mod_iface) /= mi_mod_hash (mi_final_exts our_mod_iface) + then + throwGhcExceptionIO (CmdLineError $ showSDoc dflags $ hsep + [ text "The plugin", ppr mod_name + , text "was built with a compiler that is ABI incompatible with the one loading it" + ]) ; + else -- pprTrace "(Their ABI hash, Our ABI Hash):" (ppr (mi_mod_hash $ mi_final_exts mod_iface, mi_mod_hash $ mi_final_exts our_mod_iface)) $ do { plugin_tycon <- forceLoadTyCon hsc_env plugin_name ; eith_plugin <- getValueSafely hsc_env name (mkTyConTy plugin_tycon) ; case eith_plugin of @@ -182,7 +228,7 @@ loadPlugin' occ_name plugin_name hsc_env mod_name , text "did not have the type" , text "GHC.Plugins.Plugin" , text "as required"]) - Right (plugin, links, pkgs) -> return (plugin, mod_iface, links, pkgs) } } } + Right (plugin, links, pkgs) -> return (plugin, mod_iface, links, pkgs) } } } } -- | Force the interfaces for the given modules to be loaded. The 'SDoc' parameter is used |