add linus stable bugfix directly from linux-2.6
see https://bugzilla.kernel.org/show_bug.cgi?id=16588 for details. svn path=/dists/trunk/linux-2.6/; revision=16147
This commit is contained in:
parent
c50014dac2
commit
27de5d7e30
|
@ -2,6 +2,7 @@ linux-2.6 (2.6.35-1~experimental.2) UNRELEASED; urgency=low
|
|||
|
||||
* images: Nuke modules.devname on removal. (closes: #590607)
|
||||
* Add stable 2.6.35.1 and 2.6.35.2.
|
||||
* mm: fix page table unmap for stack guard page properly.
|
||||
|
||||
-- maximilian attems <maks@debian.org> Tue, 04 Aug 2010 20:21:16 +0200
|
||||
|
||||
|
|
76
debian/patches/bugfix/all/mm-fix-page-table-unmap-for-stack-guard-page-properl.patch
vendored
Normal file
76
debian/patches/bugfix/all/mm-fix-page-table-unmap-for-stack-guard-page-properl.patch
vendored
Normal file
|
@ -0,0 +1,76 @@
|
|||
From 11ac552477e32835cb6970bf0a70c210807f5673 Mon Sep 17 00:00:00 2001
|
||||
From: Linus Torvalds <torvalds@linux-foundation.org>
|
||||
Date: Sat, 14 Aug 2010 11:44:56 -0700
|
||||
Subject: [PATCH] mm: fix page table unmap for stack guard page properly
|
||||
MIME-Version: 1.0
|
||||
Content-Type: text/plain; charset=UTF-8
|
||||
Content-Transfer-Encoding: 8bit
|
||||
|
||||
We do in fact need to unmap the page table _before_ doing the whole
|
||||
stack guard page logic, because if it is needed (mainly 32-bit x86 with
|
||||
PAE and CONFIG_HIGHPTE, but other architectures may use it too) then it
|
||||
will do a kmap_atomic/kunmap_atomic.
|
||||
|
||||
And those kmaps will create an atomic region that we cannot do
|
||||
allocations in. However, the whole stack expand code will need to do
|
||||
anon_vma_prepare() and vma_lock_anon_vma() and they cannot do that in an
|
||||
atomic region.
|
||||
|
||||
Now, a better model might actually be to do the anon_vma_prepare() when
|
||||
_creating_ a VM_GROWSDOWN segment, and not have to worry about any of
|
||||
this at page fault time. But in the meantime, this is the
|
||||
straightforward fix for the issue.
|
||||
|
||||
See https://bugzilla.kernel.org/show_bug.cgi?id=16588 for details.
|
||||
|
||||
Reported-by: Wylda <wylda@volny.cz>
|
||||
Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
|
||||
Reported-by: Mike Pagano <mpagano@gentoo.org>
|
||||
Reported-by: François Valenduc <francois.valenduc@tvcablenet.be>
|
||||
Tested-by: Ed Tomlinson <edt@aei.ca>
|
||||
Cc: Pekka Enberg <penberg@kernel.org>
|
||||
Cc: Greg KH <gregkh@suse.de>
|
||||
Cc: stable@kernel.org
|
||||
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||||
---
|
||||
mm/memory.c | 13 ++++++-------
|
||||
1 files changed, 6 insertions(+), 7 deletions(-)
|
||||
|
||||
diff --git a/mm/memory.c b/mm/memory.c
|
||||
index 9b3b73f..b6e5fd2 100644
|
||||
--- a/mm/memory.c
|
||||
+++ b/mm/memory.c
|
||||
@@ -2792,24 +2792,23 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
|
||||
spinlock_t *ptl;
|
||||
pte_t entry;
|
||||
|
||||
- if (check_stack_guard_page(vma, address) < 0) {
|
||||
- pte_unmap(page_table);
|
||||
+ pte_unmap(page_table);
|
||||
+
|
||||
+ /* Check if we need to add a guard page to the stack */
|
||||
+ if (check_stack_guard_page(vma, address) < 0)
|
||||
return VM_FAULT_SIGBUS;
|
||||
- }
|
||||
|
||||
+ /* Use the zero-page for reads */
|
||||
if (!(flags & FAULT_FLAG_WRITE)) {
|
||||
entry = pte_mkspecial(pfn_pte(my_zero_pfn(address),
|
||||
vma->vm_page_prot));
|
||||
- ptl = pte_lockptr(mm, pmd);
|
||||
- spin_lock(ptl);
|
||||
+ page_table = pte_offset_map_lock(mm, pmd, address, &ptl);
|
||||
if (!pte_none(*page_table))
|
||||
goto unlock;
|
||||
goto setpte;
|
||||
}
|
||||
|
||||
/* Allocate our own private page. */
|
||||
- pte_unmap(page_table);
|
||||
-
|
||||
if (unlikely(anon_vma_prepare(vma)))
|
||||
goto oom;
|
||||
page = alloc_zeroed_user_highpage_movable(vma, address);
|
||||
--
|
||||
1.7.1
|
||||
|
|
@ -1,2 +1,3 @@
|
|||
+ bugfix/all/stable/2.6.35.1.patch
|
||||
+ bugfix/all/stable/2.6.35.2.patch
|
||||
+ bugfix/all/mm-fix-page-table-unmap-for-stack-guard-page-properl.patch
|
||||
|
|
Loading…
Reference in New Issue