diff options
author | Andrey Ryabinin <aryabinin@virtuozzo.com> | 2018-08-18 01:47:04 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-18 02:20:30 +0300 |
commit | 0207df4fa1a869281ddbf72db6203dbf036b3e1a (patch) | |
tree | ff843a903d9149fd06632658d4984dc724e5e7fa /include/linux | |
parent | 50f8b92f21d23789bd4ada593e8ddc56cc4f79fe (diff) | |
download | linux-0207df4fa1a869281ddbf72db6203dbf036b3e1a.tar.xz |
kernel/memremap, kasan: make ZONE_DEVICE with work with KASAN
KASAN learns about hotadded memory via the memory hotplug notifier.
devm_memremap_pages() intentionally skips calling memory hotplug
notifiers. So KASAN doesn't know anything about new memory added by
devm_memremap_pages(). This causes a crash when KASAN tries to access
non-existent shadow memory:
BUG: unable to handle kernel paging request at ffffed0078000000
RIP: 0010:check_memory_region+0x82/0x1e0
Call Trace:
memcpy+0x1f/0x50
pmem_do_bvec+0x163/0x720
pmem_make_request+0x305/0xac0
generic_make_request+0x54f/0xcf0
submit_bio+0x9c/0x370
submit_bh_wbc+0x4c7/0x700
block_read_full_page+0x5ef/0x870
do_read_cache_page+0x2b8/0xb30
read_dev_sector+0xbd/0x3f0
read_lba.isra.0+0x277/0x670
efi_partition+0x41a/0x18f0
check_partition+0x30d/0x5e9
rescan_partitions+0x18c/0x840
__blkdev_get+0x859/0x1060
blkdev_get+0x23f/0x810
__device_add_disk+0x9c8/0xde0
pmem_attach_disk+0x9a8/0xf50
nvdimm_bus_probe+0xf3/0x3c0
driver_probe_device+0x493/0xbd0
bus_for_each_drv+0x118/0x1b0
__device_attach+0x1cd/0x2b0
bus_probe_device+0x1ac/0x260
device_add+0x90d/0x1380
nd_async_device_register+0xe/0x50
async_run_entry_fn+0xc3/0x5d0
process_one_work+0xa0a/0x1810
worker_thread+0x87/0xe80
kthread+0x2d7/0x390
ret_from_fork+0x3a/0x50
Add kasan_add_zero_shadow()/kasan_remove_zero_shadow() - post mm_init()
interface to map/unmap kasan_zero_page at requested virtual addresses.
And use it to add/remove the shadow memory for hotplugged/unplugged
device memory.
Link: http://lkml.kernel.org/r/20180629164932.740-1-aryabinin@virtuozzo.com
Fixes: 41e94a851304 ("add devm_memremap_pages")
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reported-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux')
-rw-r--r-- | include/linux/kasan.h | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/include/linux/kasan.h b/include/linux/kasan.h index de784fd11d12..46aae129917c 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -20,7 +20,7 @@ extern pmd_t kasan_zero_pmd[PTRS_PER_PMD]; extern pud_t kasan_zero_pud[PTRS_PER_PUD]; extern p4d_t kasan_zero_p4d[MAX_PTRS_PER_P4D]; -void kasan_populate_zero_shadow(const void *shadow_start, +int kasan_populate_zero_shadow(const void *shadow_start, const void *shadow_end); static inline void *kasan_mem_to_shadow(const void *addr) @@ -71,6 +71,9 @@ struct kasan_cache { int kasan_module_alloc(void *addr, size_t size); void kasan_free_shadow(const struct vm_struct *vm); +int kasan_add_zero_shadow(void *start, unsigned long size); +void kasan_remove_zero_shadow(void *start, unsigned long size); + size_t ksize(const void *); static inline void kasan_unpoison_slab(const void *ptr) { ksize(ptr); } size_t kasan_metadata_size(struct kmem_cache *cache); @@ -124,6 +127,14 @@ static inline bool kasan_slab_free(struct kmem_cache *s, void *object, static inline int kasan_module_alloc(void *addr, size_t size) { return 0; } static inline void kasan_free_shadow(const struct vm_struct *vm) {} +static inline int kasan_add_zero_shadow(void *start, unsigned long size) +{ + return 0; +} +static inline void kasan_remove_zero_shadow(void *start, + unsigned long size) +{} + static inline void kasan_unpoison_slab(const void *ptr) { } static inline size_t kasan_metadata_size(struct kmem_cache *cache) { return 0; } |