ARM: 9202/1: kasan: support CONFIG_KASAN_VMALLOC

Simply make shadow of vmalloc area mapped on demand.

Since the virtual address of vmalloc for Arm is also between
MODULE_VADDR and 0x100000000 (ZONE_HIGHMEM), which means the shadow
address has already included between KASAN_SHADOW_START and
KASAN_SHADOW_END.
Thus we need to change nothing for memory map of Arm.

This can fix ARM_MODULE_PLTS with KASan, support KASan for higmem
and support CONFIG_VMAP_STACK with KASan.

Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 7630ba9..545d2d4 100644 (file)
--- 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 5ad0d6c..29caee9 100644 (file)
--- a/arch/arm/mm/kasan_init.c
+++ b/arch/arm/mm/kasan_init.c
@@ -236,7 +236,11 @@ 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))
+               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) {