From: deraadt <deraadt@openbsd.org>
Date: Wed, 25 Jan 2023 23:42:03 +0000 (+0000)
Subject: In the previous commit, FIXPROT would upgrade a PROT_NONE mapping too far.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=c74ea1ce49c33a5a0b9c9686e76338d41ee46261;p=openbsd

In the previous commit, FIXPROT would upgrade a PROT_NONE mapping too far.
Correct the logic, still blocking PROT_EXEC
ok anton kettenis
---

diff --git a/sys/uvm/uvm_map.c b/sys/uvm/uvm_map.c
index f99ac269303..f5c23a642b9 100644
--- a/sys/uvm/uvm_map.c
+++ b/sys/uvm/uvm_map.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_map.c,v 1.307 2023/01/24 00:16:08 deraadt Exp $	*/
+/*	$OpenBSD: uvm_map.c,v 1.308 2023/01/25 23:42:03 deraadt Exp $	*/
 /*	$NetBSD: uvm_map.c,v 1.86 2000/11/27 08:40:03 chs Exp $	*/
 
 /*
@@ -4469,9 +4469,12 @@ uvm_map_extract(struct vm_map *srcmap, vaddr_t start, vsize_t len,
 			goto fail2_unmap;
 		}
 		kernel_map->size += cp_len;
-		if (flags & UVM_EXTRACT_FIXPROT)
-			newentry->protection = newentry->max_protection &
-			    ~PROT_EXEC;
+
+		/* Figure out the best protection */ 
+		if ((flags & UVM_EXTRACT_FIXPROT) &&
+		    newentry->protection != PROT_NONE)
+			newentry->protection = newentry->max_protection;
+		newentry->protection &= ~PROT_EXEC;
 
 		/*
 		 * Step 2: perform pmap copy.