mseal sysmap: enable x86-64

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.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Jeff Xu <[email protected]>
Reviewed-by: Lorenzo Stoakes <[email protected]>
Reviewed-by: Liam R. Howlett <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Cc: Adhemerval Zanella <[email protected]>
Cc: Alexander Mikhalitsyn <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Cc: Andrei Vagin <[email protected]>
Cc: Anna-Maria Behnsen <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Benjamin Berg <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Elliot Hughes <[email protected]>
Cc: Florian Faineli <[email protected]>
Cc: Greg Ungerer <[email protected]>
Cc: Guenter Roeck <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Helge Deller <[email protected]>
Cc: Hyeonggon Yoo <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jann Horn <[email protected]>
Cc: Jason A. Donenfeld <[email protected]>
Cc: Johannes Berg <[email protected]>
Cc: Jorge Lucangeli Obes <[email protected]>
Cc: Linus Waleij <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Matthew Wilcow (Oracle) <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Miguel Ojeda <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Pedro Falcato <[email protected]>
Cc: Peter Xu <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Stephen Röttger <[email protected]>
Cc: Thomas Weißschuh <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: peaktocreek

arch/x86/Kconfig

@@ -27,6 +27,7 @@ config X86_64
 	# Options that are inherently 64-bit kernel only:
 	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_HAS_PTDUMP
+	select ARCH_SUPPORTS_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

arch/x86/entry/vdso/vma.c

@@ -162,7 +162,8 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
 				       text_start,
 				       image->size,
 				       VM_READ|VM_EXEC|
-				       VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
+				       VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
+				       VM_SEALED_SYSMAP,
 				       &vdso_mapping);
 
 	if (IS_ERR(vma)) {
@@ -181,7 +182,7 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
 				       VDSO_VCLOCK_PAGES_START(addr),
 				       VDSO_NR_VCLOCK_PAGES * PAGE_SIZE,
 				       VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|
-				       VM_PFNMAP,
+				       VM_PFNMAP|VM_SEALED_SYSMAP,
 				       &vvar_vclock_mapping);
 
 	if (IS_ERR(vma)) {