@@ -755,6 +755,7 @@ CFLAGS_KASAN_MINIMAL := $(call cc-option, -fsanitize=kernel-address)
CFLAGS_KASAN := $(call cc-option, -fsanitize=kernel-address \
-fasan-shadow-offset=$(CONFIG_KASAN_SHADOW_OFFSET) \
+ --param asan-stack=1 \
--param asan-instrumentation-with-call-threshold=$(call_threshold))
ifeq ($(CFLAGS_KASAN_MINIMAL),)
@@ -1,17 +1,23 @@
#ifndef _ASM_X86_PAGE_64_DEFS_H
#define _ASM_X86_PAGE_64_DEFS_H
-#define THREAD_SIZE_ORDER 2
+#ifdef CONFIG_KASAN
+#define KASAN_STACK_ORDER 1
+#else
+#define KASAN_STACK_ORDER 0
+#endif
+
+#define THREAD_SIZE_ORDER (2 + KASAN_STACK_ORDER)
#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
#define CURRENT_MASK (~(THREAD_SIZE - 1))
-#define EXCEPTION_STACK_ORDER 0
+#define EXCEPTION_STACK_ORDER (0 + KASAN_STACK_ORDER)
#define EXCEPTION_STKSZ (PAGE_SIZE << EXCEPTION_STACK_ORDER)
#define DEBUG_STACK_ORDER (EXCEPTION_STACK_ORDER + 1)
#define DEBUG_STKSZ (PAGE_SIZE << DEBUG_STACK_ORDER)
-#define IRQ_STACK_ORDER 2
+#define IRQ_STACK_ORDER (2 + KASAN_STACK_ORDER)
#define IRQ_STACK_SIZE (PAGE_SIZE << IRQ_STACK_ORDER)
#define DOUBLEFAULT_STACK 1
@@ -17,6 +17,8 @@ CFLAGS_REMOVE_early_printk.o = -pg
endif
KASAN_SANITIZE_head$(BITS).o := n
+KASAN_SANITIZE_dumpstack.o := n
+KASAN_SANITIZE_dumpstack_$(BITS).o := n
CFLAGS_irq.o := -I$(src)/../include/asm/trace
@@ -207,9 +207,17 @@ void __init kasan_init(void)
kasan_mem_to_shadow(KASAN_SHADOW_END));
populate_zero_shadow(kasan_mem_to_shadow(KASAN_SHADOW_END),
+ kasan_mem_to_shadow(__START_KERNEL_map));
+
+ vmemmap_populate(kasan_mem_to_shadow((unsigned long)_stext),
+ kasan_mem_to_shadow((unsigned long)_end),
+ NUMA_NO_NODE);
+
+ populate_zero_shadow(kasan_mem_to_shadow(MODULES_VADDR),
KASAN_SHADOW_END);
memset(kasan_poisoned_page, KASAN_SHADOW_GAP, PAGE_SIZE);
load_cr3(init_level4_pgt);
+ init_task.kasan_depth = 0;
}
@@ -175,6 +175,13 @@ extern struct task_group root_task_group;
# define INIT_NUMA_BALANCING(tsk)
#endif
+#ifdef CONFIG_KASAN
+# define INIT_KASAN(tsk) \
+ .kasan_depth = 1,
+#else
+# define INIT_KASAN(tsk)
+#endif
+
/*
* INIT_TASK is used to set up the first task table, touch at
* your own risk!. Base=0, limit=0x1fffff (=2MB)
@@ -247,6 +254,7 @@ extern struct task_group root_task_group;
INIT_RT_MUTEXES(tsk) \
INIT_VTIME(tsk) \
INIT_NUMA_BALANCING(tsk) \
+ INIT_KASAN(tsk) \
}
@@ -17,6 +17,15 @@ struct page;
#define KASAN_KMALLOC_FREE 0xFB /* object was freed (kmem_cache_free/kfree) */
#define KASAN_SHADOW_GAP 0xF9 /* address belongs to shadow memory */
+/*
+ * Stack redzone shadow values
+ * (Those are compiler's ABI, don't change them)
+ */
+#define KASAN_STACK_LEFT 0xF1
+#define KASAN_STACK_MID 0xF2
+#define KASAN_STACK_RIGHT 0xF3
+#define KASAN_STACK_PARTIAL 0xF4
+
#include <asm/kasan.h>
#include <linux/sched.h>
@@ -67,6 +67,12 @@ static void print_error_description(struct access_info *info)
case KASAN_SHADOW_GAP:
bug_type = "wild memory access";
break;
+ case KASAN_STACK_LEFT:
+ case KASAN_STACK_MID:
+ case KASAN_STACK_RIGHT:
+ case KASAN_STACK_PARTIAL:
+ bug_type = "out of bounds on stack";
+ break;
}
pr_err("BUG: AddressSanitizer: %s in %pS at addr %p\n",
Stack instrumentation allows to detect out of bounds memory accesses for variables allocated on stack. Compiler adds redzones around every variable on stack and poisons redzones in function's prologue. Such approach significantly increases stack usage, so all in-kernel stacks size were doubled. Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com> --- Makefile | 1 + arch/x86/include/asm/page_64_types.h | 12 +++++++++--- arch/x86/kernel/Makefile | 2 ++ arch/x86/mm/kasan_init_64.c | 8 ++++++++ include/linux/init_task.h | 8 ++++++++ include/linux/kasan.h | 9 +++++++++ mm/kasan/report.c | 6 ++++++ 7 files changed, 43 insertions(+), 3 deletions(-)