diff options
| author | Breno Leitao <leitao@debian.org> | 2025-07-04 05:47:07 -0700 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2025-07-04 14:47:06 +0100 |
| commit | ef8923e6c051a98164c2889db943df9695a39888 (patch) | |
| tree | ea5eee060784a73c7b77ce9564ed597d52a0b58c | |
| parent | 39dfc971e42d886e7df01371cd1bef505076d84c (diff) | |
arm64: efi: Fix KASAN false positive for EFI runtime stack
KASAN reports invalid accesses during arch_stack_walk() for EFI runtime
services due to vmalloc tagging[1]. The EFI runtime stack must be allocated
with KASAN tags reset to avoid false positives.
This patch uses arch_alloc_vmap_stack() instead of __vmalloc_node() for
EFI stack allocation, which internally calls kasan_reset_tag()
The changes ensure EFI runtime stacks are properly sanitized for KASAN
while maintaining functional consistency.
Link: https://lore.kernel.org/all/aFVVEgD0236LdrL6@gmail.com/ [1]
Suggested-by: Andrey Konovalov <andreyknvl@gmail.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://lore.kernel.org/r/20250704-arm_kasan-v2-1-32ebb4fd7607@debian.org
Signed-off-by: Will Deacon <will@kernel.org>
| -rw-r--r-- | arch/arm64/kernel/efi.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c index 3857fd7ee8d4..62230d6dd919 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -15,6 +15,7 @@ #include <asm/efi.h> #include <asm/stacktrace.h> +#include <asm/vmap_stack.h> static bool region_is_misaligned(const efi_memory_desc_t *md) { @@ -214,9 +215,13 @@ static int __init arm64_efi_rt_init(void) if (!efi_enabled(EFI_RUNTIME_SERVICES)) return 0; - p = __vmalloc_node(THREAD_SIZE, THREAD_ALIGN, GFP_KERNEL, - NUMA_NO_NODE, &&l); -l: if (!p) { + if (!IS_ENABLED(CONFIG_VMAP_STACK)) { + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); + return -ENOMEM; + } + + p = arch_alloc_vmap_stack(THREAD_SIZE, NUMA_NO_NODE); + if (!p) { pr_warn("Failed to allocate EFI runtime stack\n"); clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); return -ENOMEM; |