[PATCH 3/3] UML - pte_mkread fix

From: Jeff Dike
Date: Tue Feb 20 2007 - 12:06:23 EST

Fix the fact that pte_mkread set _PAGE_RW instead of _PAGE_USER (the logic is
copied from i386 in most place, so it is really as bad as you're thinking).

Thus currently page tables are more permissive than they should.

Such a change may trigger other latent bugs, so be careful with this.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@xxxxxxxx>
Signed-off-by: Jeff Dike <jdike@xxxxxxxxxxx>
include/asm-um/pgtable.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-2.6.18-mm/include/asm-um/pgtable.h
--- linux-2.6.18-mm.orig/include/asm-um/pgtable.h 2006-10-03 12:53:16.000000000 -0400
+++ linux-2.6.18-mm/include/asm-um/pgtable.h 2006-10-09 12:25:44.000000000 -0400
@@ -270,7 +270,7 @@ static inline pte_t pte_wrprotect(pte_t

static inline pte_t pte_mkread(pte_t pte)
- pte_set_bits(pte, _PAGE_RW);
+ pte_set_bits(pte, _PAGE_USER);

Work email - jdike at linux dot intel dot com
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