From: deraadt <deraadt@openbsd.org>
Date: Wed, 9 Nov 2022 19:50:25 +0000 (+0000)
Subject: Now that dlopen() sets object->nodelete for RTLD_NODELETE, _dl_load_dep_libs()
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=82e9b32ad49a55c04069e26596c5b24c2e9f5e0e;p=openbsd

Now that dlopen() sets object->nodelete for RTLD_NODELETE, _dl_load_dep_libs()
can consider this same as the "booting" case, and instruct lower layers to
do immutability. With this change in place, the not-yet-commited
library-immutable diff leaves 1 page of libc (malloc related) and 6
non-RTLD_NODELETE libraries mutable in chrome.
Everything else is immutable, except for the program's transient memory
allocations & file mappings.  This is an unexpected result.
---

diff --git a/libexec/ld.so/loader.c b/libexec/ld.so/loader.c
index 4d08adfd633..c1922d06ee5 100644
--- a/libexec/ld.so/loader.c
+++ b/libexec/ld.so/loader.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: loader.c,v 1.203 2022/11/08 13:47:22 deraadt Exp $ */
+/*	$OpenBSD: loader.c,v 1.204 2022/11/09 19:50:25 deraadt Exp $ */
 
 /*
  * Copyright (c) 1998 Per Fogelstrom, Opsycon AB
@@ -320,7 +320,7 @@ _dl_load_dep_libs(elf_object_t *object, int flags, int booting)
 	Elf_Dyn *dynp;
 	unsigned int loop;
 	int libcount;
-	int depflags;
+	int depflags, nodelete = 0;
 
 	dynobj = object;
 	while (dynobj) {
@@ -329,6 +329,8 @@ _dl_load_dep_libs(elf_object_t *object, int flags, int booting)
 
 		/* propagate DF_1_NOW to deplibs (can be set by dynamic tags) */
 		depflags = flags | (dynobj->obj_flags & DF_1_NOW);
+		if (booting || object->nodelete)
+			nodelete = 1;
 
 		for (dynp = dynobj->load_dyn; dynp->d_tag; dynp++) {
 			if (dynp->d_tag == DT_NEEDED) {
@@ -379,7 +381,7 @@ _dl_load_dep_libs(elf_object_t *object, int flags, int booting)
 				DL_DEB(("loading: %s required by %s\n", libname,
 				    dynobj->load_name));
 				depobj = _dl_load_shlib(libname, dynobj,
-				    OBJTYPE_LIB, depflags, booting);
+				    OBJTYPE_LIB, depflags, nodelete);
 				if (depobj == 0) {
 					if (booting) {
 						_dl_die(