[ros-diffs] [reactos] 01/01: [NTOS:MM] Fix PTE protection for executable CoW pages

[Timo Kreuzer]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=c0590f5de0fd4747fbe78…

commit c0590f5de0fd4747fbe78bbfea21d9972daeacf7
Author:     Timo Kreuzer <timo.kreuzer(a)reactos.org>
AuthorDate: Mon Sep 23 21:26:37 2024 +0300
Commit:     Timo Kreuzer <timo.kreuzer(a)reactos.org>
CommitDate: Thu Oct 10 17:37:56 2024 +0300

    [NTOS:MM] Fix PTE protection for executable CoW pages
    
    Fixes Blender x64.
    See https://jira.reactos.org/browse/CORE-19761
---
 ntoskrnl/mm/section.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/ntoskrnl/mm/section.c b/ntoskrnl/mm/section.c
index 1949d026149..f935e6f30c1 100644
--- a/ntoskrnl/mm/section.c
+++ b/ntoskrnl/mm/section.c
@@ -1509,7 +1509,12 @@ MmAlterViewAttributes(PMMSUPPORT AddressSpace,
                  */
                 Page = MmGetPfnForProcess(Process, Address);
 
-                Protect = PAGE_READONLY;
+                /* Choose protection based on what was requested */
+                if (NewProtect == PAGE_EXECUTE_READWRITE)
+                    Protect = PAGE_EXECUTE_READ;
+                else
+                    Protect = PAGE_READONLY;
+
                 if (IS_SWAP_FROM_SSE(Entry) || PFN_FROM_SSE(Entry) != Page)
                 {
                     Protect = NewProtect;