dect/linux-2.6
Archived
14
0
Fork 0
Code Releases Activity

[PATCH] uml: fix fault handler on write

Browse source 
The UML fault handler was recently changed to enforce PROT_NONE protections,
by requiring VM_READ or VM_EXEC on VMA's.

However, by mistake, things were changed such that VM_READ is always checked,
also on write faults; so a VMA mapped with only PROT_WRITE is not readable
(unless it's prefaulted with MAP_POPULATE or with a write), which is different
from i386.

Discovered while testing remap_file_pages protection support.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Paolo 'Blaisorblade' Giarrusso 2005-09-10 19:44:57 +02:00 committed by Linus Torvalds
parent d99c4022f6
commit d129f31236
1 changed files with 2 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
arch/um/kernel/trap_kern.c
View file

@ -57,7 +57,8 @@ good_area:
if(is_write && !(vma->vm_flags & VM_WRITE))
goto out;
if(!(vma->vm_flags & (VM_READ | VM_EXEC)))
/* Don't require VM_READ|VM_EXEC for write faults! */
if(!is_write && !(vma->vm_flags & (VM_READ | VM_EXEC)))
goto out;
do {