diff --git a/reactos/ntoskrnl/include/internal/mm.h b/reactos/ntoskrnl/include/internal/mm.h
index c76b669ff75..ca0ef374933 100644
--- a/reactos/ntoskrnl/include/internal/mm.h
+++ b/reactos/ntoskrnl/include/internal/mm.h
@@ -140,6 +140,16 @@ typedef ULONG PFN_TYPE, *PPFN_TYPE;
     PAGE_NOACCESS | \
     PAGE_NOCACHE)
 
+#define PAGE_FLAGS_VALID_FOR_SECTION \
+    (PAGE_READONLY | \
+     PAGE_READWRITE | \
+     PAGE_WRITECOPY | \
+     PAGE_EXECUTE | \
+     PAGE_EXECUTE_READ | \
+     PAGE_EXECUTE_READWRITE | \
+     PAGE_EXECUTE_WRITECOPY | \
+     PAGE_NOACCESS)
+
 #define PAGE_IS_READABLE                    \
     (PAGE_READONLY | \
     PAGE_READWRITE | \
diff --git a/reactos/ntoskrnl/mm/anonmem.c b/reactos/ntoskrnl/mm/anonmem.c
index b75c6b7e874..30456dc9124 100644
--- a/reactos/ntoskrnl/mm/anonmem.c
+++ b/reactos/ntoskrnl/mm/anonmem.c
@@ -569,7 +569,7 @@ NtAllocateVirtualMemory(IN     HANDLE ProcessHandle,
           Protect);
 
    /* Check for valid protection flags */
-   if (!(Protect & PAGE_FLAGS_VALID_FROM_USER_MODE))
+   if (!Protect || Protect & ~PAGE_FLAGS_VALID_FROM_USER_MODE)
    {
       DPRINT1("Invalid page protection\n");
       return STATUS_INVALID_PAGE_PROTECTION;
diff --git a/reactos/ntoskrnl/mm/section.c b/reactos/ntoskrnl/mm/section.c
index 5c2eb518e40..e09044b44eb 100644
--- a/reactos/ntoskrnl/mm/section.c
+++ b/reactos/ntoskrnl/mm/section.c
@@ -4538,10 +4538,7 @@ MmMapViewOfSection(IN PVOID SectionObject,
 
    ASSERT(Process);
 
-   if (!(Protect & (PAGE_READONLY | PAGE_READWRITE | 
-                   PAGE_WRITECOPY | PAGE_EXECUTE |
-                   PAGE_EXECUTE_READ | PAGE_EXECUTE_READWRITE |
-                   PAGE_EXECUTE_WRITECOPY | PAGE_NOACCESS)))
+   if (!Protect || Protect & ~PAGE_FLAGS_VALID_FOR_SECTION)
    {
       return STATUS_INVALID_PAGE_PROTECTION;
    }