Re: [PATCH] [4.2 fix] x86, mpx: do not set ->vm_ops on mpx VMAs
On Tue, Aug 04, 2015 at 12:39:13AM +0300, Kirill A. Shutemov wrote: > On Mon, Aug 03, 2015 at 01:36:23PM -0700, Greg KH wrote: > > On Mon, Aug 03, 2015 at 10:40:55PM +0300, Kirill A. Shutemov wrote: > > > On Mon, Aug 03, 2015 at 09:19:14AM -0700, Greg KH wrote: > > > > On Mon, Aug 03, 2015 at 01:34:28PM +0300, Kirill A. Shutemov wrote: > > > > > Greg KH wrote: > > > > > > On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote: > > > > > > > > > > > > > > (sorry for the spam, I screwed up the stable@ address). > > > > > > > > > > > > > > BTW, thanks to Kirill for doing this patch! He posted it to LKML > > > > > > > but we need to ensure it is picked up for 4.2 and any -stable > > > > > > > kernels where this commit is applied: > > > > > > > > > > > > > > 6b7339f4: mm: avoid setting up anonymous pages into > > > > > > > file mapping > > > > > > > > > > > > > > That broke MPX support because MPX sets a vma->vm_ops on an > > > > > > > anonymous VMA. We need this patch to make it work again, > > > > > > > basically removing MPX's use of ->vm_ops. Kirill made me aware > > > > > > > of this long ago, but I didn't double-check that his fix got > > > > > > > submitted and merged. > > > > > > > > > > > > > > I (Dave) fixed up a minor merge conflict and added the > > > > > > > try_unmap_single_bt() use of is_mpx_vma() (which were added > > > > > > > post-4.1). > > > > > > > > > > > > > > Note for -stable: The first hunk may not apply cleanly because of > > > > > > > other activity in arch/x86/mm/mmap.c, but should be trivial to > > > > > > > apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc > > > > > > > kernels. > > > > > > > > > > > > Can someone send a version that is known to apply, you don't want to > > > > > > rely on me to get it right :) > > > > > > > > > > Here it is. > > > > > > > > > > MPX support was introduced in 3.19, so it only need to be applied to > > > > > 4.1-stable. > > > > > > > > Thanks, now applied. > > > > > > Just to make clear: we don't need MPX patch for older stables, but we > > > *do* need 6b7339f4 (mm: avoid setting up anonymous pages into file > > > mapping) to be ported into all stables. > > > > Can you provide that backport, it isn't a direct cherry-pick. > > Patches are in attach. > > 0001-mm-avoid-setting-up-anonymous-pages-3.18.patch is rebased onto v3.18. > Thanks, I'm queuing this for the 3.16 kernel as well. Cheers, -- Luís > 0001-mm-avoid-setting-up-anonymous-pages-3.14.patch is rebased onto v3.14, > also applies cleanly to v3.12, v3.10, v3.4, v3.2. > > 0001-mm-avoid-setting-up-anonymous-pages-2.6.32.patch is rebased onto > v2.6.32. > > Build tested for all these versions. > > -- > Kirill A. Shutemov -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] [4.2 fix] x86, mpx: do not set -vm_ops on mpx VMAs
On Tue, Aug 04, 2015 at 12:39:13AM +0300, Kirill A. Shutemov wrote: On Mon, Aug 03, 2015 at 01:36:23PM -0700, Greg KH wrote: On Mon, Aug 03, 2015 at 10:40:55PM +0300, Kirill A. Shutemov wrote: On Mon, Aug 03, 2015 at 09:19:14AM -0700, Greg KH wrote: On Mon, Aug 03, 2015 at 01:34:28PM +0300, Kirill A. Shutemov wrote: Greg KH wrote: On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote: (sorry for the spam, I screwed up the stable@ address). BTW, thanks to Kirill for doing this patch! He posted it to LKML but we need to ensure it is picked up for 4.2 and any -stable kernels where this commit is applied: 6b7339f4: mm: avoid setting up anonymous pages into file mapping That broke MPX support because MPX sets a vma-vm_ops on an anonymous VMA. We need this patch to make it work again, basically removing MPX's use of -vm_ops. Kirill made me aware of this long ago, but I didn't double-check that his fix got submitted and merged. I (Dave) fixed up a minor merge conflict and added the try_unmap_single_bt() use of is_mpx_vma() (which were added post-4.1). Note for -stable: The first hunk may not apply cleanly because of other activity in arch/x86/mm/mmap.c, but should be trivial to apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels. Can someone send a version that is known to apply, you don't want to rely on me to get it right :) Here it is. MPX support was introduced in 3.19, so it only need to be applied to 4.1-stable. Thanks, now applied. Just to make clear: we don't need MPX patch for older stables, but we *do* need 6b7339f4 (mm: avoid setting up anonymous pages into file mapping) to be ported into all stables. Can you provide that backport, it isn't a direct cherry-pick. Patches are in attach. 0001-mm-avoid-setting-up-anonymous-pages-3.18.patch is rebased onto v3.18. Thanks, I'm queuing this for the 3.16 kernel as well. Cheers, -- Luís 0001-mm-avoid-setting-up-anonymous-pages-3.14.patch is rebased onto v3.14, also applies cleanly to v3.12, v3.10, v3.4, v3.2. 0001-mm-avoid-setting-up-anonymous-pages-2.6.32.patch is rebased onto v2.6.32. Build tested for all these versions. -- Kirill A. Shutemov -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] [4.2 fix] x86, mpx: do not set ->vm_ops on mpx VMAs
On Tue, Aug 04, 2015 at 12:39:13AM +0300, Kirill A. Shutemov wrote: > On Mon, Aug 03, 2015 at 01:36:23PM -0700, Greg KH wrote: > > On Mon, Aug 03, 2015 at 10:40:55PM +0300, Kirill A. Shutemov wrote: > > > On Mon, Aug 03, 2015 at 09:19:14AM -0700, Greg KH wrote: > > > > On Mon, Aug 03, 2015 at 01:34:28PM +0300, Kirill A. Shutemov wrote: > > > > > Greg KH wrote: > > > > > > On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote: > > > > > > > > > > > > > > (sorry for the spam, I screwed up the stable@ address). > > > > > > > > > > > > > > BTW, thanks to Kirill for doing this patch! He posted it to LKML > > > > > > > but we need to ensure it is picked up for 4.2 and any -stable > > > > > > > kernels where this commit is applied: > > > > > > > > > > > > > > 6b7339f4: mm: avoid setting up anonymous pages into > > > > > > > file mapping > > > > > > > > > > > > > > That broke MPX support because MPX sets a vma->vm_ops on an > > > > > > > anonymous VMA. We need this patch to make it work again, > > > > > > > basically removing MPX's use of ->vm_ops. Kirill made me aware > > > > > > > of this long ago, but I didn't double-check that his fix got > > > > > > > submitted and merged. > > > > > > > > > > > > > > I (Dave) fixed up a minor merge conflict and added the > > > > > > > try_unmap_single_bt() use of is_mpx_vma() (which were added > > > > > > > post-4.1). > > > > > > > > > > > > > > Note for -stable: The first hunk may not apply cleanly because of > > > > > > > other activity in arch/x86/mm/mmap.c, but should be trivial to > > > > > > > apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc > > > > > > > kernels. > > > > > > > > > > > > Can someone send a version that is known to apply, you don't want to > > > > > > rely on me to get it right :) > > > > > > > > > > Here it is. > > > > > > > > > > MPX support was introduced in 3.19, so it only need to be applied to > > > > > 4.1-stable. > > > > > > > > Thanks, now applied. > > > > > > Just to make clear: we don't need MPX patch for older stables, but we > > > *do* need 6b7339f4 (mm: avoid setting up anonymous pages into file > > > mapping) to be ported into all stables. > > > > Can you provide that backport, it isn't a direct cherry-pick. > > Patches are in attach. > > 0001-mm-avoid-setting-up-anonymous-pages-3.18.patch is rebased onto v3.18. > > 0001-mm-avoid-setting-up-anonymous-pages-3.14.patch is rebased onto v3.14, > also applies cleanly to v3.12, v3.10, v3.4, v3.2. Thanks, I've taken this patch now for 3.10 and 3.14. greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] [4.2 fix] x86, mpx: do not set -vm_ops on mpx VMAs
On Tue, Aug 04, 2015 at 12:39:13AM +0300, Kirill A. Shutemov wrote: On Mon, Aug 03, 2015 at 01:36:23PM -0700, Greg KH wrote: On Mon, Aug 03, 2015 at 10:40:55PM +0300, Kirill A. Shutemov wrote: On Mon, Aug 03, 2015 at 09:19:14AM -0700, Greg KH wrote: On Mon, Aug 03, 2015 at 01:34:28PM +0300, Kirill A. Shutemov wrote: Greg KH wrote: On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote: (sorry for the spam, I screwed up the stable@ address). BTW, thanks to Kirill for doing this patch! He posted it to LKML but we need to ensure it is picked up for 4.2 and any -stable kernels where this commit is applied: 6b7339f4: mm: avoid setting up anonymous pages into file mapping That broke MPX support because MPX sets a vma-vm_ops on an anonymous VMA. We need this patch to make it work again, basically removing MPX's use of -vm_ops. Kirill made me aware of this long ago, but I didn't double-check that his fix got submitted and merged. I (Dave) fixed up a minor merge conflict and added the try_unmap_single_bt() use of is_mpx_vma() (which were added post-4.1). Note for -stable: The first hunk may not apply cleanly because of other activity in arch/x86/mm/mmap.c, but should be trivial to apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels. Can someone send a version that is known to apply, you don't want to rely on me to get it right :) Here it is. MPX support was introduced in 3.19, so it only need to be applied to 4.1-stable. Thanks, now applied. Just to make clear: we don't need MPX patch for older stables, but we *do* need 6b7339f4 (mm: avoid setting up anonymous pages into file mapping) to be ported into all stables. Can you provide that backport, it isn't a direct cherry-pick. Patches are in attach. 0001-mm-avoid-setting-up-anonymous-pages-3.18.patch is rebased onto v3.18. 0001-mm-avoid-setting-up-anonymous-pages-3.14.patch is rebased onto v3.14, also applies cleanly to v3.12, v3.10, v3.4, v3.2. Thanks, I've taken this patch now for 3.10 and 3.14. greg k-h -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] [4.2 fix] x86, mpx: do not set ->vm_ops on mpx VMAs
On Mon, Aug 03, 2015 at 01:36:23PM -0700, Greg KH wrote:
> On Mon, Aug 03, 2015 at 10:40:55PM +0300, Kirill A. Shutemov wrote:
> > On Mon, Aug 03, 2015 at 09:19:14AM -0700, Greg KH wrote:
> > > On Mon, Aug 03, 2015 at 01:34:28PM +0300, Kirill A. Shutemov wrote:
> > > > Greg KH wrote:
> > > > > On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote:
> > > > > >
> > > > > > (sorry for the spam, I screwed up the stable@ address).
> > > > > >
> > > > > > BTW, thanks to Kirill for doing this patch! He posted it to LKML
> > > > > > but we need to ensure it is picked up for 4.2 and any -stable
> > > > > > kernels where this commit is applied:
> > > > > >
> > > > > > 6b7339f4: mm: avoid setting up anonymous pages into
> > > > > > file mapping
> > > > > >
> > > > > > That broke MPX support because MPX sets a vma->vm_ops on an
> > > > > > anonymous VMA. We need this patch to make it work again,
> > > > > > basically removing MPX's use of ->vm_ops. Kirill made me aware
> > > > > > of this long ago, but I didn't double-check that his fix got
> > > > > > submitted and merged.
> > > > > >
> > > > > > I (Dave) fixed up a minor merge conflict and added the
> > > > > > try_unmap_single_bt() use of is_mpx_vma() (which were added
> > > > > > post-4.1).
> > > > > >
> > > > > > Note for -stable: The first hunk may not apply cleanly because of
> > > > > > other activity in arch/x86/mm/mmap.c, but should be trivial to
> > > > > > apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels.
> > > > >
> > > > > Can someone send a version that is known to apply, you don't want to
> > > > > rely on me to get it right :)
> > > >
> > > > Here it is.
> > > >
> > > > MPX support was introduced in 3.19, so it only need to be applied to
> > > > 4.1-stable.
> > >
> > > Thanks, now applied.
> >
> > Just to make clear: we don't need MPX patch for older stables, but we
> > *do* need 6b7339f4 (mm: avoid setting up anonymous pages into file
> > mapping) to be ported into all stables.
>
> Can you provide that backport, it isn't a direct cherry-pick.
Patches are in attach.
0001-mm-avoid-setting-up-anonymous-pages-3.18.patch is rebased onto v3.18.
0001-mm-avoid-setting-up-anonymous-pages-3.14.patch is rebased onto v3.14,
also applies cleanly to v3.12, v3.10, v3.4, v3.2.
0001-mm-avoid-setting-up-anonymous-pages-2.6.32.patch is rebased onto
v2.6.32.
Build tested for all these versions.
--
Kirill A. Shutemov
>From 41456c4806bb0b4561602e037183790020a13532 Mon Sep 17 00:00:00 2001
From: "Kirill A. Shutemov"
Date: Mon, 6 Jul 2015 23:18:37 +0300
Subject: [PATCH] mm: avoid setting up anonymous pages into file mapping
Reading page fault handler code I've noticed that under right
circumstances kernel would map anonymous pages into file mappings: if
the VMA doesn't have vm_ops->fault() and the VMA wasn't fully populated
on ->mmap(), kernel would handle page fault to not populated pte with
do_anonymous_page().
Let's change page fault handler to use do_anonymous_page() only on
anonymous VMA (->vm_ops == NULL) and make sure that the VMA is not
shared.
For file mappings without vm_ops->fault() or shred VMA without vm_ops,
page fault on pte_none() entry would lead to SIGBUS.
Signed-off-by: Kirill A. Shutemov
Acked-by: Oleg Nesterov
Cc: Andrew Morton
Cc: Willy Tarreau
Cc: sta...@vger.kernel.org
Signed-off-by: Linus Torvalds
---
mm/memory.c | 14 ++
1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c
index d5f2ae9c4a23..04979a2b3eb4 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2636,6 +2636,10 @@ static int do_anonymous_page(struct mm_struct *mm,
struct vm_area_struct *vma,
pte_unmap(page_table);
+ /* File mapping without ->vm_ops ? */
+ if (vma->vm_flags & VM_SHARED)
+ return VM_FAULT_SIGBUS;
+
/* Check if we need to add a guard page to the stack */
if (check_stack_guard_page(vma, address) < 0)
return VM_FAULT_SIGBUS;
@@ -3040,6 +3044,9 @@ static int do_linear_fault(struct mm_struct *mm, struct
vm_area_struct *vma,
- vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
pte_unmap(page_table);
+ /* The VMA was not fully populated on mmap() or missing VM_DONTEXPAND */
+ if (!vma->vm_ops->fault)
+ return VM_FAULT_SIGBUS;
if (!(flags & FAULT_FLAG_WRITE))
return do_read_fault(mm, vma, address, pmd, pgoff, flags,
orig_pte);
@@ -3205,11 +3212,10 @@ static int handle_pte_fault(struct mm_struct *mm,
entry = ACCESS_ONCE(*pte);
if (!pte_present(entry)) {
if (pte_none(entry)) {
- if (vma->vm_ops) {
- if (likely(vma->vm_ops->fault))
- return do_linear_fault(mm, vma, address,
+ if (vma->vm_ops)
+ return
Re: [PATCH] [4.2 fix] x86, mpx: do not set ->vm_ops on mpx VMAs
On Mon, Aug 03, 2015 at 10:40:55PM +0300, Kirill A. Shutemov wrote: > On Mon, Aug 03, 2015 at 09:19:14AM -0700, Greg KH wrote: > > On Mon, Aug 03, 2015 at 01:34:28PM +0300, Kirill A. Shutemov wrote: > > > Greg KH wrote: > > > > On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote: > > > > > > > > > > (sorry for the spam, I screwed up the stable@ address). > > > > > > > > > > BTW, thanks to Kirill for doing this patch! He posted it to LKML > > > > > but we need to ensure it is picked up for 4.2 and any -stable > > > > > kernels where this commit is applied: > > > > > > > > > > 6b7339f4: mm: avoid setting up anonymous pages into file mapping > > > > > > > > > > That broke MPX support because MPX sets a vma->vm_ops on an > > > > > anonymous VMA. We need this patch to make it work again, > > > > > basically removing MPX's use of ->vm_ops. Kirill made me aware > > > > > of this long ago, but I didn't double-check that his fix got > > > > > submitted and merged. > > > > > > > > > > I (Dave) fixed up a minor merge conflict and added the > > > > > try_unmap_single_bt() use of is_mpx_vma() (which were added > > > > > post-4.1). > > > > > > > > > > Note for -stable: The first hunk may not apply cleanly because of > > > > > other activity in arch/x86/mm/mmap.c, but should be trivial to > > > > > apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels. > > > > > > > > Can someone send a version that is known to apply, you don't want to > > > > rely on me to get it right :) > > > > > > Here it is. > > > > > > MPX support was introduced in 3.19, so it only need to be applied to > > > 4.1-stable. > > > > Thanks, now applied. > > Just to make clear: we don't need MPX patch for older stables, but we > *do* need 6b7339f4 (mm: avoid setting up anonymous pages into file > mapping) to be ported into all stables. Can you provide that backport, it isn't a direct cherry-pick. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] [4.2 fix] x86, mpx: do not set ->vm_ops on mpx VMAs
On Mon, Aug 03, 2015 at 09:19:14AM -0700, Greg KH wrote: > On Mon, Aug 03, 2015 at 01:34:28PM +0300, Kirill A. Shutemov wrote: > > Greg KH wrote: > > > On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote: > > > > > > > > (sorry for the spam, I screwed up the stable@ address). > > > > > > > > BTW, thanks to Kirill for doing this patch! He posted it to LKML > > > > but we need to ensure it is picked up for 4.2 and any -stable > > > > kernels where this commit is applied: > > > > > > > > 6b7339f4: mm: avoid setting up anonymous pages into file mapping > > > > > > > > That broke MPX support because MPX sets a vma->vm_ops on an > > > > anonymous VMA. We need this patch to make it work again, > > > > basically removing MPX's use of ->vm_ops. Kirill made me aware > > > > of this long ago, but I didn't double-check that his fix got > > > > submitted and merged. > > > > > > > > I (Dave) fixed up a minor merge conflict and added the > > > > try_unmap_single_bt() use of is_mpx_vma() (which were added > > > > post-4.1). > > > > > > > > Note for -stable: The first hunk may not apply cleanly because of > > > > other activity in arch/x86/mm/mmap.c, but should be trivial to > > > > apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels. > > > > > > Can someone send a version that is known to apply, you don't want to > > > rely on me to get it right :) > > > > Here it is. > > > > MPX support was introduced in 3.19, so it only need to be applied to > > 4.1-stable. > > Thanks, now applied. Just to make clear: we don't need MPX patch for older stables, but we *do* need 6b7339f4 (mm: avoid setting up anonymous pages into file mapping) to be ported into all stables. -- Kirill A. Shutemov -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] [4.2 fix] x86, mpx: do not set ->vm_ops on mpx VMAs
On Mon, Aug 03, 2015 at 01:34:28PM +0300, Kirill A. Shutemov wrote: > Greg KH wrote: > > On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote: > > > > > > (sorry for the spam, I screwed up the stable@ address). > > > > > > BTW, thanks to Kirill for doing this patch! He posted it to LKML > > > but we need to ensure it is picked up for 4.2 and any -stable > > > kernels where this commit is applied: > > > > > > 6b7339f4: mm: avoid setting up anonymous pages into file mapping > > > > > > That broke MPX support because MPX sets a vma->vm_ops on an > > > anonymous VMA. We need this patch to make it work again, > > > basically removing MPX's use of ->vm_ops. Kirill made me aware > > > of this long ago, but I didn't double-check that his fix got > > > submitted and merged. > > > > > > I (Dave) fixed up a minor merge conflict and added the > > > try_unmap_single_bt() use of is_mpx_vma() (which were added > > > post-4.1). > > > > > > Note for -stable: The first hunk may not apply cleanly because of > > > other activity in arch/x86/mm/mmap.c, but should be trivial to > > > apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels. > > > > Can someone send a version that is known to apply, you don't want to > > rely on me to get it right :) > > Here it is. > > MPX support was introduced in 3.19, so it only need to be applied to > 4.1-stable. Thanks, now applied. greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] [4.2 fix] x86, mpx: do not set ->vm_ops on mpx VMAs
Greg KH wrote:
> On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote:
> >
> > (sorry for the spam, I screwed up the stable@ address).
> >
> > BTW, thanks to Kirill for doing this patch! He posted it to LKML
> > but we need to ensure it is picked up for 4.2 and any -stable
> > kernels where this commit is applied:
> >
> > 6b7339f4: mm: avoid setting up anonymous pages into file mapping
> >
> > That broke MPX support because MPX sets a vma->vm_ops on an
> > anonymous VMA. We need this patch to make it work again,
> > basically removing MPX's use of ->vm_ops. Kirill made me aware
> > of this long ago, but I didn't double-check that his fix got
> > submitted and merged.
> >
> > I (Dave) fixed up a minor merge conflict and added the
> > try_unmap_single_bt() use of is_mpx_vma() (which were added
> > post-4.1).
> >
> > Note for -stable: The first hunk may not apply cleanly because of
> > other activity in arch/x86/mm/mmap.c, but should be trivial to
> > apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels.
>
> Can someone send a version that is known to apply, you don't want to
> rely on me to get it right :)
Here it is.
MPX support was introduced in 3.19, so it only need to be applied to
4.1-stable.
>From 62d8093f0bfd79eff2c87e8924cb9276116aaabe Mon Sep 17 00:00:00 2001
From: "Kirill A. Shutemov"
Date: Mon, 20 Jul 2015 14:29:58 -0700
Subject: [PATCH] x86/mpx: Do not set ->vm_ops on MPX VMAs
MPX setups private anonymous mapping, but uses vma->vm_ops too.
This can confuse core VM, as it relies on vm->vm_ops to
distinguish file VMAs from anonymous.
As result we will get SIGBUS, because handle_pte_fault() thinks
it's file VMA without vm_ops->fault and it doesn't know how to
handle the situation properly.
Let's fix that by not setting ->vm_ops.
We don't really need ->vm_ops here: MPX VMA can be detected with
VM_MPX flag. And vma_merge() will not merge MPX VMA with non-MPX
VMA, because ->vm_flags won't match.
The only thing left is name of VMA. I'm not sure if it's part of
ABI, or we can just drop it. The patch keep it by providing
arch_vma_name() on x86.
Signed-off-by: Kirill A. Shutemov
Signed-off-by: Dave Hansen
Cc: # Fixes: 6b7339f4 (mm: avoid setting up anonymous
pages into file mapping)
Cc: Andy Lutomirski
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: d...@sr71.net
Link: http://lkml.kernel.org/r/20150720212958.305cc...@viggo.jf.intel.com
Signed-off-by: Ingo Molnar
---
arch/x86/mm/mmap.c | 7 +++
arch/x86/mm/mpx.c | 20 +---
2 files changed, 8 insertions(+), 19 deletions(-)
diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c
index 9d518d693b4b..844b06d67df4 100644
--- a/arch/x86/mm/mmap.c
+++ b/arch/x86/mm/mmap.c
@@ -126,3 +126,10 @@ void arch_pick_mmap_layout(struct mm_struct *mm)
mm->get_unmapped_area = arch_get_unmapped_area_topdown;
}
}
+
+const char *arch_vma_name(struct vm_area_struct *vma)
+{
+ if (vma->vm_flags & VM_MPX)
+ return "[mpx]";
+ return NULL;
+}
diff --git a/arch/x86/mm/mpx.c b/arch/x86/mm/mpx.c
index c439ec478216..4d1c11c07fe1 100644
--- a/arch/x86/mm/mpx.c
+++ b/arch/x86/mm/mpx.c
@@ -18,26 +18,9 @@
#include
#include
-static const char *mpx_mapping_name(struct vm_area_struct *vma)
-{
- return "[mpx]";
-}
-
-static struct vm_operations_struct mpx_vma_ops = {
- .name = mpx_mapping_name,
-};
-
-static int is_mpx_vma(struct vm_area_struct *vma)
-{
- return (vma->vm_ops == _vma_ops);
-}
-
/*
* This is really a simplified "vm_mmap". it only handles MPX
* bounds tables (the bounds directory is user-allocated).
- *
- * Later on, we use the vma->vm_ops to uniquely identify these
- * VMAs.
*/
static unsigned long mpx_mmap(unsigned long len)
{
@@ -83,7 +66,6 @@ static unsigned long mpx_mmap(unsigned long len)
ret = -ENOMEM;
goto out;
}
- vma->vm_ops = _vma_ops;
if (vm_flags & VM_LOCKED) {
up_write(>mmap_sem);
@@ -661,7 +643,7 @@ static int zap_bt_entries(struct mm_struct *mm,
* so stop immediately and return an error. This
* probably results in a SIGSEGV.
*/
- if (!is_mpx_vma(vma))
+ if (!(vma->vm_flags & VM_MPX))
return -EINVAL;
len = min(vma->vm_end, end) - addr;
--
2.4.6
--
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Re: [PATCH] [4.2 fix] x86, mpx: do not set -vm_ops on mpx VMAs
On Mon, Aug 03, 2015 at 01:34:28PM +0300, Kirill A. Shutemov wrote: Greg KH wrote: On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote: (sorry for the spam, I screwed up the stable@ address). BTW, thanks to Kirill for doing this patch! He posted it to LKML but we need to ensure it is picked up for 4.2 and any -stable kernels where this commit is applied: 6b7339f4: mm: avoid setting up anonymous pages into file mapping That broke MPX support because MPX sets a vma-vm_ops on an anonymous VMA. We need this patch to make it work again, basically removing MPX's use of -vm_ops. Kirill made me aware of this long ago, but I didn't double-check that his fix got submitted and merged. I (Dave) fixed up a minor merge conflict and added the try_unmap_single_bt() use of is_mpx_vma() (which were added post-4.1). Note for -stable: The first hunk may not apply cleanly because of other activity in arch/x86/mm/mmap.c, but should be trivial to apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels. Can someone send a version that is known to apply, you don't want to rely on me to get it right :) Here it is. MPX support was introduced in 3.19, so it only need to be applied to 4.1-stable. Thanks, now applied. greg k-h -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] [4.2 fix] x86, mpx: do not set -vm_ops on mpx VMAs
On Mon, Aug 03, 2015 at 01:36:23PM -0700, Greg KH wrote:
On Mon, Aug 03, 2015 at 10:40:55PM +0300, Kirill A. Shutemov wrote:
On Mon, Aug 03, 2015 at 09:19:14AM -0700, Greg KH wrote:
On Mon, Aug 03, 2015 at 01:34:28PM +0300, Kirill A. Shutemov wrote:
Greg KH wrote:
On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote:
(sorry for the spam, I screwed up the stable@ address).
BTW, thanks to Kirill for doing this patch! He posted it to LKML
but we need to ensure it is picked up for 4.2 and any -stable
kernels where this commit is applied:
6b7339f4: mm: avoid setting up anonymous pages into
file mapping
That broke MPX support because MPX sets a vma-vm_ops on an
anonymous VMA. We need this patch to make it work again,
basically removing MPX's use of -vm_ops. Kirill made me aware
of this long ago, but I didn't double-check that his fix got
submitted and merged.
I (Dave) fixed up a minor merge conflict and added the
try_unmap_single_bt() use of is_mpx_vma() (which were added
post-4.1).
Note for -stable: The first hunk may not apply cleanly because of
other activity in arch/x86/mm/mmap.c, but should be trivial to
apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels.
Can someone send a version that is known to apply, you don't want to
rely on me to get it right :)
Here it is.
MPX support was introduced in 3.19, so it only need to be applied to
4.1-stable.
Thanks, now applied.
Just to make clear: we don't need MPX patch for older stables, but we
*do* need 6b7339f4 (mm: avoid setting up anonymous pages into file
mapping) to be ported into all stables.
Can you provide that backport, it isn't a direct cherry-pick.
Patches are in attach.
0001-mm-avoid-setting-up-anonymous-pages-3.18.patch is rebased onto v3.18.
0001-mm-avoid-setting-up-anonymous-pages-3.14.patch is rebased onto v3.14,
also applies cleanly to v3.12, v3.10, v3.4, v3.2.
0001-mm-avoid-setting-up-anonymous-pages-2.6.32.patch is rebased onto
v2.6.32.
Build tested for all these versions.
--
Kirill A. Shutemov
From 41456c4806bb0b4561602e037183790020a13532 Mon Sep 17 00:00:00 2001
From: Kirill A. Shutemov kirill.shute...@linux.intel.com
Date: Mon, 6 Jul 2015 23:18:37 +0300
Subject: [PATCH] mm: avoid setting up anonymous pages into file mapping
Reading page fault handler code I've noticed that under right
circumstances kernel would map anonymous pages into file mappings: if
the VMA doesn't have vm_ops-fault() and the VMA wasn't fully populated
on -mmap(), kernel would handle page fault to not populated pte with
do_anonymous_page().
Let's change page fault handler to use do_anonymous_page() only on
anonymous VMA (-vm_ops == NULL) and make sure that the VMA is not
shared.
For file mappings without vm_ops-fault() or shred VMA without vm_ops,
page fault on pte_none() entry would lead to SIGBUS.
Signed-off-by: Kirill A. Shutemov kirill.shute...@linux.intel.com
Acked-by: Oleg Nesterov o...@redhat.com
Cc: Andrew Morton a...@linux-foundation.org
Cc: Willy Tarreau w...@1wt.eu
Cc: sta...@vger.kernel.org
Signed-off-by: Linus Torvalds torva...@linux-foundation.org
---
mm/memory.c | 14 ++
1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c
index d5f2ae9c4a23..04979a2b3eb4 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2636,6 +2636,10 @@ static int do_anonymous_page(struct mm_struct *mm,
struct vm_area_struct *vma,
pte_unmap(page_table);
+ /* File mapping without -vm_ops ? */
+ if (vma-vm_flags VM_SHARED)
+ return VM_FAULT_SIGBUS;
+
/* Check if we need to add a guard page to the stack */
if (check_stack_guard_page(vma, address) 0)
return VM_FAULT_SIGBUS;
@@ -3040,6 +3044,9 @@ static int do_linear_fault(struct mm_struct *mm, struct
vm_area_struct *vma,
- vma-vm_start) PAGE_SHIFT) + vma-vm_pgoff;
pte_unmap(page_table);
+ /* The VMA was not fully populated on mmap() or missing VM_DONTEXPAND */
+ if (!vma-vm_ops-fault)
+ return VM_FAULT_SIGBUS;
if (!(flags FAULT_FLAG_WRITE))
return do_read_fault(mm, vma, address, pmd, pgoff, flags,
orig_pte);
@@ -3205,11 +3212,10 @@ static int handle_pte_fault(struct mm_struct *mm,
entry = ACCESS_ONCE(*pte);
if (!pte_present(entry)) {
if (pte_none(entry)) {
- if (vma-vm_ops) {
- if (likely(vma-vm_ops-fault))
- return do_linear_fault(mm, vma, address,
+ if (vma-vm_ops)
+ return do_linear_fault(mm, vma, address,
pte, pmd, flags,
Re: [PATCH] [4.2 fix] x86, mpx: do not set -vm_ops on mpx VMAs
Greg KH wrote:
On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote:
(sorry for the spam, I screwed up the stable@ address).
BTW, thanks to Kirill for doing this patch! He posted it to LKML
but we need to ensure it is picked up for 4.2 and any -stable
kernels where this commit is applied:
6b7339f4: mm: avoid setting up anonymous pages into file mapping
That broke MPX support because MPX sets a vma-vm_ops on an
anonymous VMA. We need this patch to make it work again,
basically removing MPX's use of -vm_ops. Kirill made me aware
of this long ago, but I didn't double-check that his fix got
submitted and merged.
I (Dave) fixed up a minor merge conflict and added the
try_unmap_single_bt() use of is_mpx_vma() (which were added
post-4.1).
Note for -stable: The first hunk may not apply cleanly because of
other activity in arch/x86/mm/mmap.c, but should be trivial to
apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels.
Can someone send a version that is known to apply, you don't want to
rely on me to get it right :)
Here it is.
MPX support was introduced in 3.19, so it only need to be applied to
4.1-stable.
From 62d8093f0bfd79eff2c87e8924cb9276116aaabe Mon Sep 17 00:00:00 2001
From: Kirill A. Shutemov kirill.shute...@linux.intel.com
Date: Mon, 20 Jul 2015 14:29:58 -0700
Subject: [PATCH] x86/mpx: Do not set -vm_ops on MPX VMAs
MPX setups private anonymous mapping, but uses vma-vm_ops too.
This can confuse core VM, as it relies on vm-vm_ops to
distinguish file VMAs from anonymous.
As result we will get SIGBUS, because handle_pte_fault() thinks
it's file VMA without vm_ops-fault and it doesn't know how to
handle the situation properly.
Let's fix that by not setting -vm_ops.
We don't really need -vm_ops here: MPX VMA can be detected with
VM_MPX flag. And vma_merge() will not merge MPX VMA with non-MPX
VMA, because -vm_flags won't match.
The only thing left is name of VMA. I'm not sure if it's part of
ABI, or we can just drop it. The patch keep it by providing
arch_vma_name() on x86.
Signed-off-by: Kirill A. Shutemov kirill.shute...@linux.intel.com
Signed-off-by: Dave Hansen dave.han...@linux.intel.com
Cc: sta...@vger.kernel.org # Fixes: 6b7339f4 (mm: avoid setting up anonymous
pages into file mapping)
Cc: Andy Lutomirski l...@amacapital.net
Cc: Linus Torvalds torva...@linux-foundation.org
Cc: Peter Zijlstra pet...@infradead.org
Cc: Thomas Gleixner t...@linutronix.de
Cc: d...@sr71.net
Link: http://lkml.kernel.org/r/20150720212958.305cc...@viggo.jf.intel.com
Signed-off-by: Ingo Molnar mi...@kernel.org
---
arch/x86/mm/mmap.c | 7 +++
arch/x86/mm/mpx.c | 20 +---
2 files changed, 8 insertions(+), 19 deletions(-)
diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c
index 9d518d693b4b..844b06d67df4 100644
--- a/arch/x86/mm/mmap.c
+++ b/arch/x86/mm/mmap.c
@@ -126,3 +126,10 @@ void arch_pick_mmap_layout(struct mm_struct *mm)
mm-get_unmapped_area = arch_get_unmapped_area_topdown;
}
}
+
+const char *arch_vma_name(struct vm_area_struct *vma)
+{
+ if (vma-vm_flags VM_MPX)
+ return [mpx];
+ return NULL;
+}
diff --git a/arch/x86/mm/mpx.c b/arch/x86/mm/mpx.c
index c439ec478216..4d1c11c07fe1 100644
--- a/arch/x86/mm/mpx.c
+++ b/arch/x86/mm/mpx.c
@@ -18,26 +18,9 @@
#include asm/processor.h
#include asm/fpu-internal.h
-static const char *mpx_mapping_name(struct vm_area_struct *vma)
-{
- return [mpx];
-}
-
-static struct vm_operations_struct mpx_vma_ops = {
- .name = mpx_mapping_name,
-};
-
-static int is_mpx_vma(struct vm_area_struct *vma)
-{
- return (vma-vm_ops == mpx_vma_ops);
-}
-
/*
* This is really a simplified vm_mmap. it only handles MPX
* bounds tables (the bounds directory is user-allocated).
- *
- * Later on, we use the vma-vm_ops to uniquely identify these
- * VMAs.
*/
static unsigned long mpx_mmap(unsigned long len)
{
@@ -83,7 +66,6 @@ static unsigned long mpx_mmap(unsigned long len)
ret = -ENOMEM;
goto out;
}
- vma-vm_ops = mpx_vma_ops;
if (vm_flags VM_LOCKED) {
up_write(mm-mmap_sem);
@@ -661,7 +643,7 @@ static int zap_bt_entries(struct mm_struct *mm,
* so stop immediately and return an error. This
* probably results in a SIGSEGV.
*/
- if (!is_mpx_vma(vma))
+ if (!(vma-vm_flags VM_MPX))
return -EINVAL;
len = min(vma-vm_end, end) - addr;
--
2.4.6
--
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Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] [4.2 fix] x86, mpx: do not set -vm_ops on mpx VMAs
On Mon, Aug 03, 2015 at 09:19:14AM -0700, Greg KH wrote: On Mon, Aug 03, 2015 at 01:34:28PM +0300, Kirill A. Shutemov wrote: Greg KH wrote: On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote: (sorry for the spam, I screwed up the stable@ address). BTW, thanks to Kirill for doing this patch! He posted it to LKML but we need to ensure it is picked up for 4.2 and any -stable kernels where this commit is applied: 6b7339f4: mm: avoid setting up anonymous pages into file mapping That broke MPX support because MPX sets a vma-vm_ops on an anonymous VMA. We need this patch to make it work again, basically removing MPX's use of -vm_ops. Kirill made me aware of this long ago, but I didn't double-check that his fix got submitted and merged. I (Dave) fixed up a minor merge conflict and added the try_unmap_single_bt() use of is_mpx_vma() (which were added post-4.1). Note for -stable: The first hunk may not apply cleanly because of other activity in arch/x86/mm/mmap.c, but should be trivial to apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels. Can someone send a version that is known to apply, you don't want to rely on me to get it right :) Here it is. MPX support was introduced in 3.19, so it only need to be applied to 4.1-stable. Thanks, now applied. Just to make clear: we don't need MPX patch for older stables, but we *do* need 6b7339f4 (mm: avoid setting up anonymous pages into file mapping) to be ported into all stables. -- Kirill A. Shutemov -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] [4.2 fix] x86, mpx: do not set -vm_ops on mpx VMAs
On Mon, Aug 03, 2015 at 10:40:55PM +0300, Kirill A. Shutemov wrote: On Mon, Aug 03, 2015 at 09:19:14AM -0700, Greg KH wrote: On Mon, Aug 03, 2015 at 01:34:28PM +0300, Kirill A. Shutemov wrote: Greg KH wrote: On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote: (sorry for the spam, I screwed up the stable@ address). BTW, thanks to Kirill for doing this patch! He posted it to LKML but we need to ensure it is picked up for 4.2 and any -stable kernels where this commit is applied: 6b7339f4: mm: avoid setting up anonymous pages into file mapping That broke MPX support because MPX sets a vma-vm_ops on an anonymous VMA. We need this patch to make it work again, basically removing MPX's use of -vm_ops. Kirill made me aware of this long ago, but I didn't double-check that his fix got submitted and merged. I (Dave) fixed up a minor merge conflict and added the try_unmap_single_bt() use of is_mpx_vma() (which were added post-4.1). Note for -stable: The first hunk may not apply cleanly because of other activity in arch/x86/mm/mmap.c, but should be trivial to apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels. Can someone send a version that is known to apply, you don't want to rely on me to get it right :) Here it is. MPX support was introduced in 3.19, so it only need to be applied to 4.1-stable. Thanks, now applied. Just to make clear: we don't need MPX patch for older stables, but we *do* need 6b7339f4 (mm: avoid setting up anonymous pages into file mapping) to be ported into all stables. Can you provide that backport, it isn't a direct cherry-pick. thanks, greg k-h -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] [4.2 fix] x86, mpx: do not set ->vm_ops on mpx VMAs
On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote: > > (sorry for the spam, I screwed up the stable@ address). > > BTW, thanks to Kirill for doing this patch! He posted it to LKML > but we need to ensure it is picked up for 4.2 and any -stable > kernels where this commit is applied: > > 6b7339f4: mm: avoid setting up anonymous pages into file mapping > > That broke MPX support because MPX sets a vma->vm_ops on an > anonymous VMA. We need this patch to make it work again, > basically removing MPX's use of ->vm_ops. Kirill made me aware > of this long ago, but I didn't double-check that his fix got > submitted and merged. > > I (Dave) fixed up a minor merge conflict and added the > try_unmap_single_bt() use of is_mpx_vma() (which were added > post-4.1). > > Note for -stable: The first hunk may not apply cleanly because of > other activity in arch/x86/mm/mmap.c, but should be trivial to > apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels. Can someone send a version that is known to apply, you don't want to rely on me to get it right :) thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] [4.2 fix] x86, mpx: do not set -vm_ops on mpx VMAs
On Mon, Jul 20, 2015 at 02:29:58PM -0700, Dave Hansen wrote: (sorry for the spam, I screwed up the stable@ address). BTW, thanks to Kirill for doing this patch! He posted it to LKML but we need to ensure it is picked up for 4.2 and any -stable kernels where this commit is applied: 6b7339f4: mm: avoid setting up anonymous pages into file mapping That broke MPX support because MPX sets a vma-vm_ops on an anonymous VMA. We need this patch to make it work again, basically removing MPX's use of -vm_ops. Kirill made me aware of this long ago, but I didn't double-check that his fix got submitted and merged. I (Dave) fixed up a minor merge conflict and added the try_unmap_single_bt() use of is_mpx_vma() (which were added post-4.1). Note for -stable: The first hunk may not apply cleanly because of other activity in arch/x86/mm/mmap.c, but should be trivial to apply by hand. Hunk #5 on mpx.c is only present on 4.2-rc kernels. Can someone send a version that is known to apply, you don't want to rely on me to get it right :) thanks, greg k-h -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
