==================================================================
BUG: KASAN: slab-out-of-bounds in sctp_send_reset_streams+0xadf/0xc10 net/sctp/stream.c:314
Read of size 2 at addr ffff8801d9842788 by task syz-executor3/8852

CPU: 0 PID: 8852 Comm: syz-executor3 Not tainted 4.15.0-rc3+ #220
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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_load2_noabort+0x14/0x20 mm/kasan/report.c:428
 sctp_send_reset_streams+0xadf/0xc10 net/sctp/stream.c:314
 sctp_setsockopt_reset_streams net/sctp/socket.c:3905 [inline]
 sctp_setsockopt+0x70d/0x5d50 net/sctp/socket.c:4195
 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2968
 SYSC_setsockopt net/socket.c:1829 [inline]
 SyS_setsockopt+0x189/0x360 net/socket.c:1808
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x452a39
RSP: 002b:00007ff5d3d53c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452a39
RDX: 0000000000000077 RSI: 0000000000000084 RDI: 0000000000000017
RBP: 000000000000055e R08: 0000000000000008 R09: 0000000000000000
R10: 0000000020b30000 R11: 0000000000000212 R12: 00000000006f6170
R13: 00000000ffffffff R14: 00007ff5d3d546d4 R15: 0000000000000000

Allocated by task 8852:
 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:3711 [inline]
 __kmalloc_track_caller+0x15e/0x760 mm/slab.c:3726
 memdup_user+0x2c/0x90 mm/util.c:164
 sctp_setsockopt_reset_streams net/sctp/socket.c:3897 [inline]
 sctp_setsockopt+0x6a6/0x5d50 net/sctp/socket.c:4195
 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2968
 SYSC_setsockopt net/socket.c:1829 [inline]
 SyS_setsockopt+0x189/0x360 net/socket.c:1808
 entry_SYSCALL_64_fastpath+0x1f/0x96

Freed by task 7094:
 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:3491 [inline]
 kfree+0xca/0x250 mm/slab.c:3806
 selinux_sk_free_security+0x4f/0x60 security/selinux/hooks.c:4908
 security_sk_free+0x48/0x80 security/security.c:1431
 sk_prot_free net/core/sock.c:1502 [inline]
 __sk_destruct+0x609/0x910 net/core/sock.c:1585
 sk_destruct+0x47/0x80 net/core/sock.c:1593
 __sk_free+0x57/0x230 net/core/sock.c:1601
 sk_free+0x2a/0x40 net/core/sock.c:1612
 sock_put include/net/sock.h:1651 [inline]
 dccp_close+0x6de/0xc10 net/dccp/proto.c:1086
 inet_release+0xed/0x1c0 net/ipv4/af_inet.c:426
 sock_release+0x8d/0x1e0 net/socket.c:600
 SYSC_socketpair net/socket.c:1401 [inline]
 SyS_socketpair+0x481/0x6f0 net/socket.c:1346
 entry_SYSCALL_64_fastpath+0x1f/0x96

The buggy address belongs to the object at ffff8801d9842780
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 8 bytes inside of
 32-byte region [ffff8801d9842780, ffff8801d98427a0)
The buggy address belongs to the page:
page:000000005042da1b count:1 mapcount:0 mapping:000000006740f74c index:0xffff8801d9842fc1
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801d9842000 ffff8801d9842fc1 0000000100000039
raw: ffffea0007660de0 ffffea000738c860 ffff8801db0001c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d9842680: 00 01 fc fc fc fc fc fc fb fb fb fb fc fc fc fc
 ffff8801d9842700: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
>ffff8801d9842780: 00 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc
                      ^
 ffff8801d9842800: fb fb fb fb fc fc fc fc 00 01 fc fc fc fc fc fc
 ffff8801d9842880: 00 01 fc fc fc fc fc fc fb fb fb fb fc fc fc fc
==================================================================