From: Alexandre Ghiti alexandre.ghiti@canonical.com
commit 54c5639d8f507ebefa814f574cb6f763033a72a5 upstream.
Nathan reported that because KASAN_SHADOW_OFFSET was not defined in Kconfig, it prevents asan-stack from getting disabled with clang even when CONFIG_KASAN_STACK is disabled: fix this by defining the corresponding config.
Reported-by: Nathan Chancellor nathan@kernel.org Signed-off-by: Alexandre Ghiti alexandre.ghiti@canonical.com Fixes: 8ad8b72721d0 ("riscv: Add KASAN support") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt palmerdabbelt@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/riscv/Kconfig | 6 ++++++ arch/riscv/include/asm/kasan.h | 3 +-- arch/riscv/mm/kasan_init.c | 3 +++ 3 files changed, 10 insertions(+), 2 deletions(-)
--- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -138,6 +138,12 @@ config PAGE_OFFSET default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
+config KASAN_SHADOW_OFFSET + hex + depends on KASAN_GENERIC + default 0xdfffffc800000000 if 64BIT + default 0xffffffff if 32BIT + config ARCH_FLATMEM_ENABLE def_bool y
--- a/arch/riscv/include/asm/kasan.h +++ b/arch/riscv/include/asm/kasan.h @@ -14,8 +14,7 @@ #define KASAN_SHADOW_START KERN_VIRT_START /* 2^64 - 2^38 */ #define KASAN_SHADOW_END (KASAN_SHADOW_START + KASAN_SHADOW_SIZE)
-#define KASAN_SHADOW_OFFSET (KASAN_SHADOW_END - (1ULL << \ - (64 - KASAN_SHADOW_SCALE_SHIFT))) +#define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
void kasan_init(void); asmlinkage void kasan_early_init(void); --- a/arch/riscv/mm/kasan_init.c +++ b/arch/riscv/mm/kasan_init.c @@ -16,6 +16,9 @@ asmlinkage void __init kasan_early_init( uintptr_t i; pgd_t *pgd = early_pg_dir + pgd_index(KASAN_SHADOW_START);
+ BUILD_BUG_ON(KASAN_SHADOW_OFFSET != + KASAN_SHADOW_END - (1UL << (64 - KASAN_SHADOW_SCALE_SHIFT))); + for (i = 0; i < PTRS_PER_PTE; ++i) set_pte(kasan_early_shadow_pte + i, mk_pte(virt_to_page(kasan_early_shadow_page),