From: deraadt <deraadt@openbsd.org>
Date: Wed, 12 Oct 2022 02:39:16 +0000 (+0000)
Subject: The sigaltstack() MAP_STACK re-map mechanism is incompatible with immutable
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=10781bd23a219dbb37d81e609f7ef4499f15754b;p=openbsd

The sigaltstack() MAP_STACK re-map mechanism is incompatible with immutable
regions, so immutable stack isn't viable yet. There are configure programs
which create sigstacks upon their own stacks, and there is no simple fix for
the sigaltstack mechanism...
discovered by sthen and tb
---

diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c
index 8f9fc6ec8cd..0e4ac0170fb 100644
--- a/sys/kern/kern_exec.c
+++ b/sys/kern/kern_exec.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_exec.c,v 1.234 2022/10/08 17:03:09 deraadt Exp $	*/
+/*	$OpenBSD: kern_exec.c,v 1.235 2022/10/12 02:39:16 deraadt Exp $	*/
 /*	$NetBSD: kern_exec.c,v 1.75 1996/02/09 18:59:28 christos Exp $	*/
 
 /*-
@@ -476,9 +476,6 @@ sys_execve(struct proc *p, void *v, register_t *retval)
                 goto exec_abort;
 #endif
 
-	uvm_map_immutable(&p->p_vmspace->vm_map, (vaddr_t)vm->vm_maxsaddr,
-	    (vaddr_t)vm->vm_minsaddr, 1, "stack");
-
 	memset(&arginfo, 0, sizeof(arginfo));
 
 	/* remember information about the process */