==================================================================
BUG: KASAN: use-after-free in ip6_dst_idev include/net/ip6_fib.h:141 [inline]
BUG: KASAN: use-after-free in ip6_xmit+0x177c/0x1a00 net/ipv6/ip6_output.c:237
Read of size 8 at addr ffff8801d4127a18 by task syz-executor6/9346

CPU: 1 PID: 9346 Comm: syz-executor6 Not tainted 4.4.152-ge5c5f1f #89
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 4c89e580e99e858b ffff8801bbc775c8 ffffffff81e15fed
 ffffea00075049c0 ffff8801d4127a18 0000000000000000 ffff8801d4127a18
 0000000000001000 ffff8801bbc77600 ffffffff8151b489 ffff8801d4127a18
Call Trace:
 [<ffffffff81e15fed>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81e15fed>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff8151b489>] print_address_description+0x6c/0x216 mm/kasan/report.c:252
 [<ffffffff8151b7a8>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff8151b7a8>] kasan_report.cold.7+0x175/0x2f7 mm/kasan/report.c:408
 [<ffffffff814fe734>] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:429
 [<ffffffff83435efc>] ip6_dst_idev include/net/ip6_fib.h:141 [inline]
 [<ffffffff83435efc>] ip6_xmit+0x177c/0x1a00 net/ipv6/ip6_output.c:237
 [<ffffffff834f60c5>] inet6_csk_xmit+0x245/0x490 net/ipv6/inet6_connection_sock.c:176
 [<ffffffff835a570c>] l2tp_xmit_core net/l2tp/l2tp_core.c:1084 [inline]
 [<ffffffff835a570c>] l2tp_xmit_skb+0xb9c/0xe80 net/l2tp/l2tp_core.c:1179
 [<ffffffff835b1c60>] pppol2tp_sendmsg+0x4e0/0x7d0 net/l2tp/l2tp_ppp.c:355
hid-generic 1000:0000:0001.0005: unknown main item tag 0x0
hid-generic 1000:0000:0001.0005: unknown main item tag 0x0
hid-generic 1000:0000:0001.0005: unknown main item tag 0x0
hid-generic 1000:0000:0001.0005: unknown main item tag 0x0
hid-generic 1000:0000:0001.0005: unknown main item tag 0x0
hid-generic 1000:0000:0001.0005: unknown main item tag 0x0
hid-generic 1000:0000:0001.0005: unknown main item tag 0x0
hid-generic 1000:0000:0001.0005: unknown main item tag 0x0
hid-generic 1000:0000:0001.0005: unknown main item tag 0x0
hid-generic 1000:0000:0001.0005: unknown main item tag 0x0
hid-generic 1000:0000:0001.0005: unknown main item tag 0x0
hid-generic 1000:0000:0001.0005: hidraw0: <UNKNOWN> HID v0.00 Device [syz1] on syz1
IPVS: ip_vs_svc_hash(): request for already hashed, called from do_ip_vs_set_ctl+0xb15/0xbd0 net/netfilter/ipvs/ip_vs_ctl.c:2430
hid-generic 1000:0000:0001.0006: unknown main item tag 0x0
hid-generic 1000:0000:0001.0006: unknown main item tag 0x0
hid-generic 1000:0000:0001.0006: unknown main item tag 0x0
hid-generic 1000:0000:0001.0006: unknown main item tag 0x0
hid-generic 1000:0000:0001.0006: unknown main item tag 0x0
hid-generic 1000:0000:0001.0006: unknown main item tag 0x0
hid-generic 1000:0000:0001.0006: unknown main item tag 0x0
hid-generic 1000:0000:0001.0006: unknown main item tag 0x0
hid-generic 1000:0000:0001.0006: unknown main item tag 0x0
hid-generic 1000:0000:0001.0006: unknown main item tag 0x0
hid-generic 1000:0000:0001.0006: unknown main item tag 0x0
hid-generic 1000:0000:0001.0006: hidraw0: <UNKNOWN> HID v0.00 Device [syz1] on syz1
IPVS: ip_vs_svc_hash(): request for already hashed, called from do_ip_vs_set_ctl+0xb15/0xbd0 net/netfilter/ipvs/ip_vs_ctl.c:2430
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=275 sclass=netlink_route_socket
 [<ffffffff82f2727c>] sock_sendmsg_nosec net/socket.c:638 [inline]
 [<ffffffff82f2727c>] sock_sendmsg+0xcc/0x110 net/socket.c:648
 [<ffffffff82f28a41>] ___sys_sendmsg+0x441/0x880 net/socket.c:1975
 [<ffffffff82f2b02e>] __sys_sendmmsg+0x12e/0x2e0 net/socket.c:2060
 [<ffffffff82f2b215>] SYSC_sendmmsg net/socket.c:2090 [inline]
 [<ffffffff82f2b215>] SyS_sendmmsg+0x35/0x60 net/socket.c:2085
 [<ffffffff838cc565>] entry_SYSCALL_64_fastpath+0x22/0x9e

Allocated by task 7828:
 [<ffffffff81034676>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814fd7d3>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814fdab7>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814fdab7>] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:616
 [<ffffffff814fe082>] kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:554
 [<ffffffff814f9b9e>] slab_post_alloc_hook mm/slub.c:1349 [inline]
 [<ffffffff814f9b9e>] slab_alloc_node mm/slub.c:2615 [inline]
 [<ffffffff814f9b9e>] slab_alloc mm/slub.c:2623 [inline]
 [<ffffffff814f9b9e>] kmem_cache_alloc+0xbe/0x2a0 mm/slub.c:2628
 [<ffffffff82fa5835>] dst_alloc+0xb5/0x1a0 net/core/dst.c:210
 [<ffffffff831f29c8>] rt_dst_alloc+0x78/0x430 net/ipv4/route.c:1478
 [<ffffffff831fbe8c>] __mkroute_output net/ipv4/route.c:2132 [inline]
 [<ffffffff831fbe8c>] __ip_route_output_key_hash+0x9ac/0x2380 net/ipv4/route.c:2344
 [<ffffffff831fe339>] __ip_route_output_key include/net/route.h:124 [inline]
 [<ffffffff831fe339>] ip_route_output_flow+0x29/0xa0 net/ipv4/route.c:2431
 [<ffffffff832da7c0>] udp_sendmsg+0x1480/0x1c70 net/ipv4/udp.c:1040
 [<ffffffff8349fbcd>] udpv6_sendmsg+0x12cd/0x24c0 net/ipv6/udp.c:1173
 [<ffffffff8330a633>] inet_sendmsg+0x203/0x4d0 net/ipv4/af_inet.c:755
 [<ffffffff82f2727c>] sock_sendmsg_nosec net/socket.c:638 [inline]
 [<ffffffff82f2727c>] sock_sendmsg+0xcc/0x110 net/socket.c:648
 [<ffffffff82f276b3>] kernel_sendmsg+0x43/0x50 net/socket.c:656
 [<ffffffff82f2eb42>] sock_no_sendpage+0x112/0x150 net/core/sock.c:2282
 [<ffffffff82f25a63>] kernel_sendpage+0x93/0xf0 net/socket.c:3315
 [<ffffffff82f25b4c>] sock_sendpage+0x8c/0xc0 net/socket.c:793
 [<ffffffff815badc6>] pipe_to_sendpage+0x266/0x330 fs/splice.c:724
 [<ffffffff815bd834>] splice_from_pipe_feed fs/splice.c:776 [inline]
 [<ffffffff815bd834>] __splice_from_pipe+0x364/0x790 fs/splice.c:901
 [<ffffffff815c0c49>] splice_from_pipe+0xf9/0x170 fs/splice.c:936
 [<ffffffff815c0cfc>] generic_splice_sendpage+0x3c/0x50 fs/splice.c:1109
 [<ffffffff815bafb8>] do_splice_from fs/splice.c:1128 [inline]
 [<ffffffff815bafb8>] direct_splice_actor+0x128/0x190 fs/splice.c:1294
 [<ffffffff815bc067>] splice_direct_to_actor+0x2c7/0x830 fs/splice.c:1247
 [<ffffffff815bc773>] do_splice_direct+0x1a3/0x270 fs/splice.c:1337
 [<ffffffff81526134>] do_sendfile+0x4e4/0xb80 fs/read_write.c:1227
 [<ffffffff81528123>] SYSC_sendfile64 fs/read_write.c:1282 [inline]
 [<ffffffff81528123>] SyS_sendfile64+0xc3/0x150 fs/read_write.c:1274
 [<ffffffff838cc565>] entry_SYSCALL_64_fastpath+0x22/0x9e

Freed by task 19:
 [<ffffffff81034676>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63
 [<ffffffff814fd7d3>] save_stack+0x43/0xd0 mm/kasan/kasan.c:512
 [<ffffffff814fe102>] set_track mm/kasan/kasan.c:524 [inline]
 [<ffffffff814fe102>] kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:589
 [<ffffffff814fb2ee>] slab_free_hook mm/slub.c:1383 [inline]
 [<ffffffff814fb2ee>] slab_free_freelist_hook mm/slub.c:1405 [inline]
 [<ffffffff814fb2ee>] slab_free mm/slub.c:2859 [inline]
 [<ffffffff814fb2ee>] kmem_cache_free+0xbe/0x340 mm/slub.c:2881
 [<ffffffff82fa4ae5>] dst_destroy.part.6+0x1f5/0x330 net/core/dst.c:270
 [<ffffffff82fa5165>] dst_destroy net/core/dst.c:252 [inline]
 [<ffffffff82fa5165>] dst_destroy_rcu+0x15/0x40 net/core/dst.c:295
 [<ffffffff81288d47>] __rcu_reclaim kernel/rcu/rcu.h:118 [inline]
 [<ffffffff81288d47>] rcu_do_batch kernel/rcu/tree.c:2705 [inline]
 [<ffffffff81288d47>] invoke_rcu_callbacks kernel/rcu/tree.c:2973 [inline]
 [<ffffffff81288d47>] __rcu_process_callbacks kernel/rcu/tree.c:2940 [inline]
 [<ffffffff81288d47>] rcu_process_callbacks+0x927/0x1440 kernel/rcu/tree.c:2957
 [<ffffffff838cfa7c>] __do_softirq+0x22c/0xa1a kernel/softirq.c:273

The buggy address belongs to the object at ffff8801d4127a00
 which belongs to the cache ip_dst_cache of size 208
The buggy address is located 24 bytes inside of
 208-byte region [ffff8801d4127a00, ffff8801d4127ad0)
The buggy address belongs to the page:
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 492 Comm: khungtaskd Not tainted 4.4.152-ge5c5f1f #89
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8800bac80000 task.stack: ffff8800bac50000
RIP: 0010:[<ffffffff8135c00b>]  [<ffffffff8135c00b>] check_hung_uninterruptible_tasks kernel/hung_task.c:181 [inline]
RIP: 0010:[<ffffffff8135c00b>]  [<ffffffff8135c00b>] watchdog+0x1eb/0x9a0 kernel/hung_task.c:238
RSP: 0018:ffff8800bac57d88  EFLAGS: 00010206
RAX: 0fffffffffffff50 RBX: 7ffffffffffffa80 RCX: 1ffffffff0942cd0
RDX: 0000000000000000 RSI: ffffffff8135c004 RDI: ffffea00075049c0
RBP: ffff8800bac57e00 R08: ffff8800bac80900 R09: 0000000000000000
R10: 0000000000000001 R11: ffff8800bac80000 R12: 8000000000000080
R13: 7fffffffffffffff R14: 00000000003fff55 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f050c0ce000 CR3: 00000000b5fc5000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff8135bed0 000000000000008c fffffbfff0940d05 fffffbfff0940d08
 ffff8800a3e90000 ffff8800a3e90000 ffff8800a3e90770 ffff8800a3e90448
 0000035581193177 ffff8800a41385c0 ffff8800bac80000 ffff8800bac57f20
Call Trace:
 [<ffffffff81193a28>] kthread+0x268/0x300 kernel/kthread.c:211
 [<ffffffff838cc995>] ret_from_fork+0x55/0x80 arch/x86/entry/entry_64.S:510
Code: f0 0f 84 44 04 00 00 e8 54 85 ff ff 45 8d 74 24 ff 45 85 e4 0f 85 9a 00 00 00 e9 e1 02 00 00 e8 3c 85 ff ff 48 89 d8 48 c1 e8 03 <42> 80 3c 38 00 0f 85 7e 06 00 00 48 8b 03 48 83 f8 02 0f 84 de 
RIP  [<ffffffff8135c00b>] check_hung_uninterruptible_tasks kernel/hung_task.c:181 [inline]
RIP  [<ffffffff8135c00b>] watchdog+0x1eb/0x9a0 kernel/hung_task.c:238
 RSP <ffff8800bac57d88>
------------[ cut here ]------------
WARNING: CPU: 0 PID: 3522 at lib/list_debug.c:29 __list_add+0x120/0x1c0 lib/list_debug.c:26()
list_add corruption. next->prev should be prev (ffff8801db31fef0), but was ffffffff83aaae60. (next=ffff8801bbc24888).