Commit 38dd767d authored by Andrey Konovalov's avatar Andrey Konovalov Committed by Linus Torvalds
Browse files

kasan: allow VMAP_STACK for HW_TAGS mode 

Even though hardware tag-based mode currently doesn't support checking
vmalloc allocations, it doesn't use shadow memory and works with
VMAP_STACK as is. Change VMAP_STACK definition accordingly.

Link: https://lkml.kernel.org/r/ecdb2a1658ebd88eb276dee2493518ac0e82de41.1606162397.git.andreyknvl@google.com
Link: https://linux-review.googlesource.com/id/I3552cbc12321dec82cd7372676e9372a2eb452ac


Signed-off-by: default avatarAndrey Konovalov <andreyknvl@google.com>
Reviewed-by: default avatarMarco Elver <elver@google.com>
Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Reviewed-by: default avatarDmitry Vyukov <dvyukov@google.com>
Tested-by: default avatarVincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent d56a9ef8

arch/Kconfig

+4 −4
Original line number Diff line number Diff line
@@ -976,16 +976,16 @@ config VMAP_STACK 
	default y

	bool "Use a virtually-mapped stack"

	depends on HAVE_ARCH_VMAP_STACK

	depends on !KASAN || KASAN_VMALLOC

	depends on !KASAN || KASAN_HW_TAGS || KASAN_VMALLOC

	help

	  Enable this if you want the use virtually-mapped kernel stacks

	  with guard pages.  This causes kernel stack overflows to be

	  caught immediately rather than causing difficult-to-diagnose

	  corruption.



	  To use this with KASAN, the architecture must support backing

	  virtual mappings with real shadow memory, and KASAN_VMALLOC must

	  be enabled.

	  To use this with software KASAN modes, the architecture must support

	  backing virtual mappings with real shadow memory, and KASAN_VMALLOC

	  must be enabled.



config ARCH_OPTIONAL_KERNEL_RWX

	def_bool n