[PATCH 1/2] ARM: kasan: Support CONFIG_KASAN_VMALLOC

[Alexander A Sverdlin]

From: Alexander Sverdlin <alexander.sverdlin at nokia.com>

Create KASAN mapping between VMALLOC_START and VMALLOC_END instead of
early shadow if KASAN_VMALLOC is configured.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin at nokia.com>
---
 arch/arm/Kconfig         | 1 +
 arch/arm/mm/kasan_init.c | 7 ++++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 2e8091e..f440cf5 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -75,6 +75,7 @@ config ARM
 	select HAVE_ARCH_KFENCE if MMU && !XIP_KERNEL
 	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
 	select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
+	select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
 	select HAVE_ARCH_MMAP_RND_BITS if MMU
 	select HAVE_ARCH_PFN_VALID
 	select HAVE_ARCH_SECCOMP
diff --git a/arch/arm/mm/kasan_init.c b/arch/arm/mm/kasan_init.c
index 5ad0d6c5..c2f49f7 100644
--- a/arch/arm/mm/kasan_init.c
+++ b/arch/arm/mm/kasan_init.c
@@ -236,7 +236,12 @@ void __init kasan_init(void)
 
 	clear_pgds(KASAN_SHADOW_START, KASAN_SHADOW_END);
 
-	kasan_populate_early_shadow(kasan_mem_to_shadow((void *)VMALLOC_START),
+	if (IS_ENABLED(CONFIG_KASAN_VMALLOC))
+		create_mapping((void *)VMALLOC_START, (void *)VMALLOC_END);
+	else
+		kasan_populate_early_shadow(kasan_mem_to_shadow((void *)VMALLOC_START),
+					    kasan_mem_to_shadow((void *)VMALLOC_END));
+	kasan_populate_early_shadow(kasan_mem_to_shadow((void *)VMALLOC_END),
 				    kasan_mem_to_shadow((void *)-1UL) + 1);
 
 	for_each_mem_range(i, &pa_start, &pa_end) {
-- 
2.10.2