A tag-based KASAN shadow memory cell contains a memory tag, that
corresponds to the tag in the top byte of the pointer, that points to that
memory. The native top byte value of kernel pointers is 0xff, so with
tag-based KASAN we need to initialize shadow memory to 0xff.
[cai@lca.pw: arm64: skip kmemleak for KASAN again\
Link: http://lkml.kernel.org/r/20181226020550.63712-1-cai@lca.pw
Link: http://lkml.kernel.org/r/5cc1b789aad7c99cf4f3ec5b328b147ad53edb40.1544099024.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+static phys_addr_t __init kasan_alloc_raw_page(int node)
+{
+ void *p = memblock_alloc_try_nid_raw(PAGE_SIZE, PAGE_SIZE,
+ __pa(MAX_DMA_ADDRESS),
+ MEMBLOCK_ALLOC_KASAN, node);
+ return __pa(p);
+}
+
static pte_t *__init kasan_pte_offset(pmd_t *pmdp, unsigned long addr, int node,
bool early)
{
static pte_t *__init kasan_pte_offset(pmd_t *pmdp, unsigned long addr, int node,
bool early)
{
do {
phys_addr_t page_phys = early ?
__pa_symbol(kasan_early_shadow_page)
do {
phys_addr_t page_phys = early ?
__pa_symbol(kasan_early_shadow_page)
- : kasan_alloc_zeroed_page(node);
+ : kasan_alloc_raw_page(node);
+ if (!early)
+ memset(__va(page_phys), KASAN_SHADOW_INIT, PAGE_SIZE);
next = addr + PAGE_SIZE;
set_pte(ptep, pfn_pte(__phys_to_pfn(page_phys), PAGE_KERNEL));
} while (ptep++, addr = next, addr != end && pte_none(READ_ONCE(*ptep)));
next = addr + PAGE_SIZE;
set_pte(ptep, pfn_pte(__phys_to_pfn(page_phys), PAGE_KERNEL));
} while (ptep++, addr = next, addr != end && pte_none(READ_ONCE(*ptep)));
pfn_pte(sym_to_pfn(kasan_early_shadow_page),
PAGE_KERNEL_RO));
pfn_pte(sym_to_pfn(kasan_early_shadow_page),
PAGE_KERNEL_RO));
- memset(kasan_early_shadow_page, 0, PAGE_SIZE);
+ memset(kasan_early_shadow_page, KASAN_SHADOW_INIT, PAGE_SIZE);
cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
/* At this point kasan is fully initialized. Enable error messages */
cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
/* At this point kasan is fully initialized. Enable error messages */
#ifdef CONFIG_KASAN_GENERIC
#ifdef CONFIG_KASAN_GENERIC
+#define KASAN_SHADOW_INIT 0
+
void kasan_cache_shrink(struct kmem_cache *cache);
void kasan_cache_shutdown(struct kmem_cache *cache);
void kasan_cache_shrink(struct kmem_cache *cache);
void kasan_cache_shutdown(struct kmem_cache *cache);
#endif /* CONFIG_KASAN_GENERIC */
#endif /* CONFIG_KASAN_GENERIC */
+#ifdef CONFIG_KASAN_SW_TAGS
+
+#define KASAN_SHADOW_INIT 0xFF
+
+#endif /* CONFIG_KASAN_SW_TAGS */
+
#endif /* LINUX_KASAN_H */
#endif /* LINUX_KASAN_H */
ret = __vmalloc_node_range(shadow_size, 1, shadow_start,
shadow_start + shadow_size,
ret = __vmalloc_node_range(shadow_size, 1, shadow_start,
shadow_start + shadow_size,
- GFP_KERNEL | __GFP_ZERO,
PAGE_KERNEL, VM_NO_GUARD, NUMA_NO_NODE,
__builtin_return_address(0));
if (ret) {
PAGE_KERNEL, VM_NO_GUARD, NUMA_NO_NODE,
__builtin_return_address(0));
if (ret) {
+ __memset(ret, KASAN_SHADOW_INIT, shadow_size);
find_vm_area(addr)->flags |= VM_KASAN;
kmemleak_ignore(ret);
return 0;
find_vm_area(addr)->flags |= VM_KASAN;
kmemleak_ignore(ret);
return 0;