diff mbox series

[v7,3/7] mseal, system mappings: enable x86-64

Message ID 20250224225246.3712295-4-jeffxu@google.com (mailing list archive)
State New
Headers show
Series mseal system mappings | expand

Commit Message

Jeff Xu Feb. 24, 2025, 10:52 p.m. UTC 
From: Jeff Xu <jeffxu@chromium.org>

Provide support for CONFIG_MSEAL_SYSTEM_MAPPINGS on x86-64,
covering the vdso, vvar, vvar_vclock.

Production release testing passes on Android and Chrome OS.

Signed-off-by: Jeff Xu <jeffxu@chromium.org>
---
 arch/x86/Kconfig          |  1 +
 arch/x86/entry/vdso/vma.c | 16 ++++++++++------
 2 files changed, 11 insertions(+), 6 deletions(-)

Comments

Kees Cook Feb. 25, 2025, 1:03 a.m. UTC | #1 
On Mon, Feb 24, 2025 at 10:52:42PM +0000, jeffxu@chromium.org wrote:
> From: Jeff Xu <jeffxu@chromium.org>
> 
> Provide support for CONFIG_MSEAL_SYSTEM_MAPPINGS on x86-64,
> covering the vdso, vvar, vvar_vclock.
> 
> Production release testing passes on Android and Chrome OS.
> 
> Signed-off-by: Jeff Xu <jeffxu@chromium.org>
> ---
>  arch/x86/Kconfig          |  1 +
>  arch/x86/entry/vdso/vma.c | 16 ++++++++++------
>  2 files changed, 11 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 87198d957e2f..8fa17032ca46 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -26,6 +26,7 @@ config X86_64
>  	depends on 64BIT
>  	# Options that are inherently 64-bit kernel only:
>  	select ARCH_HAS_GIGANTIC_PAGE
> +	select ARCH_HAS_MSEAL_SYSTEM_MAPPINGS
>  	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
>  	select ARCH_SUPPORTS_PER_VMA_LOCK
>  	select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
> diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
> index 39e6efc1a9ca..1b1c009f20a8 100644
> --- a/arch/x86/entry/vdso/vma.c
> +++ b/arch/x86/entry/vdso/vma.c
> @@ -247,6 +247,7 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
>  	struct mm_struct *mm = current->mm;
>  	struct vm_area_struct *vma;
>  	unsigned long text_start;
> +	unsigned long vm_flags;
>  	int ret = 0;
>  
>  	if (mmap_write_lock_killable(mm))
> @@ -264,11 +265,12 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
>  	/*
>  	 * MAYWRITE to allow gdb to COW and set breakpoints
>  	 */
> +	vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC;
> +	vm_flags |= VM_SEALED_SYSMAP;
>  	vma = _install_special_mapping(mm,
>  				       text_start,
>  				       image->size,
> -				       VM_READ|VM_EXEC|
> -				       VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
> +				       vm_flags,
>  				       &vdso_mapping);

I think these (in all patches) were supposed to be reworked without the
"vm_flags" variable addition?
Thomas Weißschuh Feb. 25, 2025, 8:08 a.m. UTC | #2 
Hi Jeff,

On Mon, Feb 24, 2025 at 10:52:42PM +0000, jeffxu@chromium.org wrote:
> From: Jeff Xu <jeffxu@chromium.org>
> 
> Provide support for CONFIG_MSEAL_SYSTEM_MAPPINGS on x86-64,
> covering the vdso, vvar, vvar_vclock.
> 
> Production release testing passes on Android and Chrome OS.
> 
> Signed-off-by: Jeff Xu <jeffxu@chromium.org>
> ---
>  arch/x86/Kconfig          |  1 +
>  arch/x86/entry/vdso/vma.c | 16 ++++++++++------
>  2 files changed, 11 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 87198d957e2f..8fa17032ca46 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -26,6 +26,7 @@ config X86_64
>  	depends on 64BIT
>  	# Options that are inherently 64-bit kernel only:
>  	select ARCH_HAS_GIGANTIC_PAGE
> +	select ARCH_HAS_MSEAL_SYSTEM_MAPPINGS
>  	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
>  	select ARCH_SUPPORTS_PER_VMA_LOCK
>  	select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
> diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
> index 39e6efc1a9ca..1b1c009f20a8 100644
> --- a/arch/x86/entry/vdso/vma.c
> +++ b/arch/x86/entry/vdso/vma.c
> @@ -247,6 +247,7 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
>  	struct mm_struct *mm = current->mm;
>  	struct vm_area_struct *vma;
>  	unsigned long text_start;
> +	unsigned long vm_flags;
>  	int ret = 0;
>  
>  	if (mmap_write_lock_killable(mm))
> @@ -264,11 +265,12 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
>  	/*
>  	 * MAYWRITE to allow gdb to COW and set breakpoints
>  	 */
> +	vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC;
> +	vm_flags |= VM_SEALED_SYSMAP;
>  	vma = _install_special_mapping(mm,
>  				       text_start,
>  				       image->size,
> -				       VM_READ|VM_EXEC|
> -				       VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
> +				       vm_flags,
>  				       &vdso_mapping);
>  
>  	if (IS_ERR(vma)) {
> @@ -276,11 +278,12 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
>  		goto up_fail;
>  	}
>  
> +	vm_flags = VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|VM_PFNMAP;
> +	vm_flags |= VM_SEALED_SYSMAP;
>  	vma = _install_special_mapping(mm,
>  				       addr,
>  				       (__VVAR_PAGES - VDSO_NR_VCLOCK_PAGES) * PAGE_SIZE,
> -				       VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|
> -				       VM_PFNMAP,
> +				       vm_flags,
>  				       &vvar_mapping);

This hunk (and the vvar mapping in the arm64 patch) will conflict with my
"Generic vDSO datapage" series.
That series is already part of the tip tree (branch timers/vdso) and scheduled
for the next merge window.

https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/log/?h=timers/vdso

The conflict resolution is fairly easy:
Move the new flag logic into lib/vdso/datastore.c

Depending on the expected mainline timing for this series either mention this
somewhere for the conflict resolution by Linus or rebase your series on top of
tip/timers/vdso.

>  	if (IS_ERR(vma)) {
> @@ -289,11 +292,12 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
>  		goto up_fail;
>  	}
>  
> +	vm_flags = VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|VM_PFNMAP;
> +	vm_flags |= VM_SEALED_SYSMAP;
>  	vma = _install_special_mapping(mm,
>  				       addr + (__VVAR_PAGES - VDSO_NR_VCLOCK_PAGES) * PAGE_SIZE,
>  				       VDSO_NR_VCLOCK_PAGES * PAGE_SIZE,
> -				       VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|
> -				       VM_PFNMAP,
> +				       vm_flags,
>  				       &vvar_vclock_mapping);
>  
>  	if (IS_ERR(vma)) {
> -- 
> 2.48.1.658.g4767266eb4-goog
>
Jeff Xu Feb. 26, 2025, 12:21 a.m. UTC | #3 
On Mon, Feb 24, 2025 at 5:03 PM Kees Cook <kees@kernel.org> wrote:
>
> On Mon, Feb 24, 2025 at 10:52:42PM +0000, jeffxu@chromium.org wrote:
> > From: Jeff Xu <jeffxu@chromium.org>
> >
> > Provide support for CONFIG_MSEAL_SYSTEM_MAPPINGS on x86-64,
> > covering the vdso, vvar, vvar_vclock.
> >
> > Production release testing passes on Android and Chrome OS.
> >
> > Signed-off-by: Jeff Xu <jeffxu@chromium.org>
> > ---
> >  arch/x86/Kconfig          |  1 +
> >  arch/x86/entry/vdso/vma.c | 16 ++++++++++------
> >  2 files changed, 11 insertions(+), 6 deletions(-)
> >
> > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> > index 87198d957e2f..8fa17032ca46 100644
> > --- a/arch/x86/Kconfig
> > +++ b/arch/x86/Kconfig
> > @@ -26,6 +26,7 @@ config X86_64
> >       depends on 64BIT
> >       # Options that are inherently 64-bit kernel only:
> >       select ARCH_HAS_GIGANTIC_PAGE
> > +     select ARCH_HAS_MSEAL_SYSTEM_MAPPINGS
> >       select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
> >       select ARCH_SUPPORTS_PER_VMA_LOCK
> >       select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
> > diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
> > index 39e6efc1a9ca..1b1c009f20a8 100644
> > --- a/arch/x86/entry/vdso/vma.c
> > +++ b/arch/x86/entry/vdso/vma.c
> > @@ -247,6 +247,7 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
> >       struct mm_struct *mm = current->mm;
> >       struct vm_area_struct *vma;
> >       unsigned long text_start;
> > +     unsigned long vm_flags;
> >       int ret = 0;
> >
> >       if (mmap_write_lock_killable(mm))
> > @@ -264,11 +265,12 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
> >       /*
> >        * MAYWRITE to allow gdb to COW and set breakpoints
> >        */
> > +     vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC;
> > +     vm_flags |= VM_SEALED_SYSMAP;
> >       vma = _install_special_mapping(mm,
> >                                      text_start,
> >                                      image->size,
> > -                                    VM_READ|VM_EXEC|
> > -                                    VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
> > +                                    vm_flags,
> >                                      &vdso_mapping);
>
> I think these (in all patches) were supposed to be reworked without the
> "vm_flags" variable addition?
>
OK.

> --
> Kees Cook
Jeff Xu Feb. 26, 2025, 12:48 a.m. UTC | #4 
On Tue, Feb 25, 2025 at 12:08 AM Thomas Weißschuh
<thomas.weissschuh@linutronix.de> wrote:
>
> Hi Jeff,
>
> On Mon, Feb 24, 2025 at 10:52:42PM +0000, jeffxu@chromium.org wrote:
> > From: Jeff Xu <jeffxu@chromium.org>
> >
> > Provide support for CONFIG_MSEAL_SYSTEM_MAPPINGS on x86-64,
> > covering the vdso, vvar, vvar_vclock.
> >
> > Production release testing passes on Android and Chrome OS.
> >
> > Signed-off-by: Jeff Xu <jeffxu@chromium.org>
> > ---
> >  arch/x86/Kconfig          |  1 +
> >  arch/x86/entry/vdso/vma.c | 16 ++++++++++------
> >  2 files changed, 11 insertions(+), 6 deletions(-)
> >
> > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> > index 87198d957e2f..8fa17032ca46 100644
> > --- a/arch/x86/Kconfig
> > +++ b/arch/x86/Kconfig
> > @@ -26,6 +26,7 @@ config X86_64
> >       depends on 64BIT
> >       # Options that are inherently 64-bit kernel only:
> >       select ARCH_HAS_GIGANTIC_PAGE
> > +     select ARCH_HAS_MSEAL_SYSTEM_MAPPINGS
> >       select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
> >       select ARCH_SUPPORTS_PER_VMA_LOCK
> >       select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
> > diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
> > index 39e6efc1a9ca..1b1c009f20a8 100644
> > --- a/arch/x86/entry/vdso/vma.c
> > +++ b/arch/x86/entry/vdso/vma.c
> > @@ -247,6 +247,7 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
> >       struct mm_struct *mm = current->mm;
> >       struct vm_area_struct *vma;
> >       unsigned long text_start;
> > +     unsigned long vm_flags;
> >       int ret = 0;
> >
> >       if (mmap_write_lock_killable(mm))
> > @@ -264,11 +265,12 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
> >       /*
> >        * MAYWRITE to allow gdb to COW and set breakpoints
> >        */
> > +     vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC;
> > +     vm_flags |= VM_SEALED_SYSMAP;
> >       vma = _install_special_mapping(mm,
> >                                      text_start,
> >                                      image->size,
> > -                                    VM_READ|VM_EXEC|
> > -                                    VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
> > +                                    vm_flags,
> >                                      &vdso_mapping);
> >
> >       if (IS_ERR(vma)) {
> > @@ -276,11 +278,12 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
> >               goto up_fail;
> >       }
> >
> > +     vm_flags = VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|VM_PFNMAP;
> > +     vm_flags |= VM_SEALED_SYSMAP;
> >       vma = _install_special_mapping(mm,
> >                                      addr,
> >                                      (__VVAR_PAGES - VDSO_NR_VCLOCK_PAGES) * PAGE_SIZE,
> > -                                    VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|
> > -                                    VM_PFNMAP,
> > +                                    vm_flags,
> >                                      &vvar_mapping);
>
> This hunk (and the vvar mapping in the arm64 patch) will conflict with my
> "Generic vDSO datapage" series.
> That series is already part of the tip tree (branch timers/vdso) and scheduled
> for the next merge window.
>
> https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/log/?h=timers/vdso
>
> The conflict resolution is fairly easy:
> Move the new flag logic into lib/vdso/datastore.c
>
Thank you for bringing this to my attention.

In your change,  it seems lib/vdso/datastore.c implements a
vdso_install_vvar_mapping(), then all the architectures call this
function.

So merging conflict won't be as straightforward.  Maybe a better
approach is that I continue resolving all the comments, based on the
latest main. Then wait for your change to be merged and submit another
version.

Thanks
-Jeff

-Jeff
Thomas Weißschuh Feb. 26, 2025, 7:35 a.m. UTC | #5 
On Tue, Feb 25, 2025 at 04:48:47PM -0800, Jeff Xu wrote:
> On Tue, Feb 25, 2025 at 12:08 AM Thomas Weißschuh
> <thomas.weissschuh@linutronix.de> wrote:
> > On Mon, Feb 24, 2025 at 10:52:42PM +0000, jeffxu@chromium.org wrote:
> > > From: Jeff Xu <jeffxu@chromium.org>
> > >
> > > Provide support for CONFIG_MSEAL_SYSTEM_MAPPINGS on x86-64,
> > > covering the vdso, vvar, vvar_vclock.
> > >
> > > Production release testing passes on Android and Chrome OS.
> > >
> > > Signed-off-by: Jeff Xu <jeffxu@chromium.org>
> > > ---
> > >  arch/x86/Kconfig          |  1 +
> > >  arch/x86/entry/vdso/vma.c | 16 ++++++++++------
> > >  2 files changed, 11 insertions(+), 6 deletions(-)
> > >
> > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> > > index 87198d957e2f..8fa17032ca46 100644
> > > --- a/arch/x86/Kconfig
> > > +++ b/arch/x86/Kconfig
> > > @@ -26,6 +26,7 @@ config X86_64
> > >       depends on 64BIT
> > >       # Options that are inherently 64-bit kernel only:
> > >       select ARCH_HAS_GIGANTIC_PAGE
> > > +     select ARCH_HAS_MSEAL_SYSTEM_MAPPINGS
> > >       select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
> > >       select ARCH_SUPPORTS_PER_VMA_LOCK
> > >       select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
> > > diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
> > > index 39e6efc1a9ca..1b1c009f20a8 100644
> > > --- a/arch/x86/entry/vdso/vma.c
> > > +++ b/arch/x86/entry/vdso/vma.c
> > > @@ -247,6 +247,7 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
> > >       struct mm_struct *mm = current->mm;
> > >       struct vm_area_struct *vma;
> > >       unsigned long text_start;
> > > +     unsigned long vm_flags;
> > >       int ret = 0;
> > >
> > >       if (mmap_write_lock_killable(mm))
> > > @@ -264,11 +265,12 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
> > >       /*
> > >        * MAYWRITE to allow gdb to COW and set breakpoints
> > >        */
> > > +     vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC;
> > > +     vm_flags |= VM_SEALED_SYSMAP;
> > >       vma = _install_special_mapping(mm,
> > >                                      text_start,
> > >                                      image->size,
> > > -                                    VM_READ|VM_EXEC|
> > > -                                    VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
> > > +                                    vm_flags,
> > >                                      &vdso_mapping);
> > >
> > >       if (IS_ERR(vma)) {
> > > @@ -276,11 +278,12 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
> > >               goto up_fail;
> > >       }
> > >
> > > +     vm_flags = VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|VM_PFNMAP;
> > > +     vm_flags |= VM_SEALED_SYSMAP;
> > >       vma = _install_special_mapping(mm,
> > >                                      addr,
> > >                                      (__VVAR_PAGES - VDSO_NR_VCLOCK_PAGES) * PAGE_SIZE,
> > > -                                    VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|
> > > -                                    VM_PFNMAP,
> > > +                                    vm_flags,
> > >                                      &vvar_mapping);
> >
> > This hunk (and the vvar mapping in the arm64 patch) will conflict with my
> > "Generic vDSO datapage" series.
> > That series is already part of the tip tree (branch timers/vdso) and scheduled
> > for the next merge window.
> >
> > https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/log/?h=timers/vdso
> >
> > The conflict resolution is fairly easy:
> > Move the new flag logic into lib/vdso/datastore.c
> >
> Thank you for bringing this to my attention.
> 
> In your change,  it seems lib/vdso/datastore.c implements a
> vdso_install_vvar_mapping(), then all the architectures call this
> function.

Correct.

At least all the architectures using the generic vDSO infrastructure,
which are the ones you care about.
Sparc for example has its own implementation.

> So merging conflict won't be as straightforward.

Wouldn't it be enough to unconditionally use VM_SEALED_SYSMAP in
vdso_install_vvar_mapping()?
The symbol is a noop on architectures or configurations where the new
functionality is not available or enabled.

> Maybe a better
> approach is that I continue resolving all the comments, based on the
> latest main. Then wait for your change to be merged and submit another
> version.

That would work, too. As you prefer.
diff mbox series

Patch

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 87198d957e2f..8fa17032ca46 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -26,6 +26,7 @@  config X86_64
 	depends on 64BIT
 	# Options that are inherently 64-bit kernel only:
 	select ARCH_HAS_GIGANTIC_PAGE
+	select ARCH_HAS_MSEAL_SYSTEM_MAPPINGS
 	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
 	select ARCH_SUPPORTS_PER_VMA_LOCK
 	select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 39e6efc1a9ca..1b1c009f20a8 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -247,6 +247,7 @@  static int map_vdso(const struct vdso_image *image, unsigned long addr)
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma;
 	unsigned long text_start;
+	unsigned long vm_flags;
 	int ret = 0;
 
 	if (mmap_write_lock_killable(mm))
@@ -264,11 +265,12 @@  static int map_vdso(const struct vdso_image *image, unsigned long addr)
 	/*
 	 * MAYWRITE to allow gdb to COW and set breakpoints
 	 */
+	vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC;
+	vm_flags |= VM_SEALED_SYSMAP;
 	vma = _install_special_mapping(mm,
 				       text_start,
 				       image->size,
-				       VM_READ|VM_EXEC|
-				       VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
+				       vm_flags,
 				       &vdso_mapping);
 
 	if (IS_ERR(vma)) {
@@ -276,11 +278,12 @@  static int map_vdso(const struct vdso_image *image, unsigned long addr)
 		goto up_fail;
 	}
 
+	vm_flags = VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|VM_PFNMAP;
+	vm_flags |= VM_SEALED_SYSMAP;
 	vma = _install_special_mapping(mm,
 				       addr,
 				       (__VVAR_PAGES - VDSO_NR_VCLOCK_PAGES) * PAGE_SIZE,
-				       VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|
-				       VM_PFNMAP,
+				       vm_flags,
 				       &vvar_mapping);
 
 	if (IS_ERR(vma)) {
@@ -289,11 +292,12 @@  static int map_vdso(const struct vdso_image *image, unsigned long addr)
 		goto up_fail;
 	}
 
+	vm_flags = VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|VM_PFNMAP;
+	vm_flags |= VM_SEALED_SYSMAP;
 	vma = _install_special_mapping(mm,
 				       addr + (__VVAR_PAGES - VDSO_NR_VCLOCK_PAGES) * PAGE_SIZE,
 				       VDSO_NR_VCLOCK_PAGES * PAGE_SIZE,
-				       VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|
-				       VM_PFNMAP,
+				       vm_flags,
 				       &vvar_vclock_mapping);
 
 	if (IS_ERR(vma)) {