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?
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)) {