Use struct sctp_assoc_value instead
==================================================================
BUG: KASAN: use-after-free in __le32_to_cpup include/uapi/linux/byteorder/little_endian.h:58 [inline]
BUG: KASAN: use-after-free in le32_to_cpuvp crypto/chacha20_generic.c:19 [inline]
BUG: KASAN: use-after-free in crypto_chacha20_init crypto/chacha20_generic.c:58 [inline]
BUG: KASAN: use-after-free in crypto_chacha20_crypt+0xb1a/0xc00 crypto/chacha20_generic.c:91
Read of size 4 at addr ffff8801c31114c0 by task kworker/1:5/19642

CPU: 1 PID: 19642 Comm: kworker/1:5 Not tainted 4.15.0-rc4+ #164
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: crypto cryptd_queue_worker
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x25b/0x340 mm/kasan/report.c:409
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429
 __le32_to_cpup include/uapi/linux/byteorder/little_endian.h:58 [inline]
 le32_to_cpuvp crypto/chacha20_generic.c:19 [inline]
 crypto_chacha20_init crypto/chacha20_generic.c:58 [inline]
 crypto_chacha20_crypt+0xb1a/0xc00 crypto/chacha20_generic.c:91
 chacha20_simd+0xe4/0x410 arch/x86/crypto/chacha20_glue.c:78
 crypto_skcipher_decrypt include/crypto/skcipher.h:463 [inline]
 cryptd_skcipher_decrypt+0x2ed/0x5c0 crypto/cryptd.c:523
 cryptd_queue_worker+0xff/0x1b0 crypto/cryptd.c:190
 process_one_work+0xbbf/0x1b10 kernel/workqueue.c:2112
 worker_thread+0x223/0x1990 kernel/workqueue.c:2246
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:515

Allocated by task 904:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
 __do_kmalloc mm/slab.c:3708 [inline]
 __kmalloc+0x162/0x760 mm/slab.c:3717
 kmalloc include/linux/slab.h:504 [inline]
 sock_kmalloc+0x112/0x190 net/core/sock.c:1989
 skcipher_accept_parent_nokey+0xde/0x4b0 crypto/algif_skcipher.c:375
 skcipher_accept_parent+0x95/0xd0 crypto/algif_skcipher.c:407
 af_alg_accept+0x125/0x670 crypto/af_alg.c:294
 alg_accept+0x46/0x60 crypto/af_alg.c:330
 SYSC_accept4+0x38d/0x870 net/socket.c:1543
 SyS_accept4 net/socket.c:1494 [inline]
 SYSC_accept net/socket.c:1577 [inline]
 SyS_accept+0x26/0x30 net/socket.c:1574
 entry_SYSCALL_64_fastpath+0x1f/0x96

Freed by task 900:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3488 [inline]
 kfree+0xd6/0x260 mm/slab.c:3803
 kzfree+0x28/0x30 mm/slab_common.c:1482
 __sock_kfree_s net/core/sock.c:2008 [inline]
 sock_kzfree_s+0x29/0x60 net/core/sock.c:2022
 skcipher_sock_destruct+0x132/0x1e0 crypto/algif_skcipher.c:358
 __sk_destruct+0xfd/0x910 net/core/sock.c:1563
 sk_destruct+0x47/0x80 net/core/sock.c:1598
 __sk_free+0xf1/0x2b0 net/core/sock.c:1609
 sk_free+0x2a/0x40 net/core/sock.c:1620
 sock_put include/net/sock.h:1652 [inline]
 af_alg_release+0x5d/0x70 crypto/af_alg.c:126
 sock_release+0x8d/0x1e0 net/socket.c:593
 sock_close+0x16/0x20 net/socket.c:1121
 __fput+0x327/0x7e0 fs/file_table.c:210
 ____fput+0x15/0x20 fs/file_table.c:244
 task_work_run+0x199/0x270 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x9bb/0x1ad0 kernel/exit.c:865
 do_group_exit+0x149/0x400 kernel/exit.c:968
 SYSC_exit_group kernel/exit.c:979 [inline]
 SyS_exit_group+0x1d/0x20 kernel/exit.c:977
 entry_SYSCALL_64_fastpath+0x1f/0x96

The buggy address belongs to the object at ffff8801c31114c0
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes inside of
 32-byte region [ffff8801c31114c0, ffff8801c31114e0)
The buggy address belongs to the page:
page:0000000021e49c2b count:1 mapcount:0 mapping:000000003955e7f6 index:0xffff8801c3111fc1
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801c3111000 ffff8801c3111fc1 000000010000003b
raw: ffffea0007322ea0 ffffea0007297960 ffff8801db0001c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c3111380: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
 ffff8801c3111400: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
>ffff8801c3111480: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
                                           ^
 ffff8801c3111500: 00 00 fc fc fc fc fc fc 03 fc fc fc fc fc fc fc
 ffff8801c3111580: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
==================================================================