==================================================================
BUG: KASAN: slab-out-of-bounds in __read_once_size include/linux/compiler.h:194 [inline]
BUG: KASAN: slab-out-of-bounds in ip6_dst_lookup_tail+0x1f15/0x1f90 net/ipv6/ip6_output.c:1026
Read of size 8 at addr ffff88809aca7764 by task syz-executor.4/4573

CPU: 1 PID: 4573 Comm: syz-executor.4 Not tainted 5.2.0-rc3+ #28
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:188
 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 kasan_report+0x12/0x20 mm/kasan/common.c:614
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132
 __read_once_size include/linux/compiler.h:194 [inline]
 ip6_dst_lookup_tail+0x1f15/0x1f90 net/ipv6/ip6_output.c:1026
 ip6_dst_lookup_flow+0xa8/0x220 net/ipv6/ip6_output.c:1150
 sctp_v6_get_dst+0x785/0x1ce0 net/sctp/ipv6.c:278
 sctp_transport_route+0x12d/0x360 net/sctp/transport.c:297
 sctp_assoc_add_peer+0x53e/0xfc0 net/sctp/associola.c:663
 sctp_process_param net/sctp/sm_make_chunk.c:2522 [inline]
 sctp_process_init+0x2458/0x2ad0 net/sctp/sm_make_chunk.c:2343
 sctp_sf_do_5_1D_ce+0x458/0x1390 net/sctp/sm_statefuns.c:767
 sctp_do_sm+0x121/0x5190 net/sctp/sm_sideeffect.c:1152
 sctp_endpoint_bh_rcv+0x451/0x950 net/sctp/endpointola.c:443
 sctp_inq_push+0x1e4/0x280 net/sctp/inqueue.c:80
 sctp_rcv+0x2807/0x35c0 net/sctp/input.c:256
 sctp6_rcv+0x17/0x30 net/sctp/ipv6.c:1049
 ip6_protocol_deliver_rcu+0x2fe/0x16c0 net/ipv6/ip6_input.c:397
 ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:438
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip6_input+0xe4/0x3f0 net/ipv6/ip6_input.c:447
 dst_input include/net/dst.h:439 [inline]
 ip6_rcv_finish+0x1de/0x310 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ipv6_rcv+0x10e/0x420 net/ipv6/ip6_input.c:272
 __netif_receive_skb_one_core+0x113/0x1a0 net/core/dev.c:4981
 __netif_receive_skb+0x2c/0x1d0 net/core/dev.c:5095
 process_backlog+0x206/0x750 net/core/dev.c:5906
 napi_poll net/core/dev.c:6329 [inline]
 net_rx_action+0x4f5/0x1070 net/core/dev.c:6395
 __do_softirq+0x25c/0x94c kernel/softirq.c:293
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1040
 </IRQ>
 do_softirq.part.0+0x11a/0x170 kernel/softirq.c:338
 do_softirq kernel/softirq.c:330 [inline]
 __local_bh_enable_ip+0x211/0x270 kernel/softirq.c:190
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:682 [inline]
 ip6_finish_output2+0x10a0/0x2550 net/ipv6/ip6_output.c:117
 __ip6_finish_output+0x444/0xaa0 net/ipv6/ip6_output.c:142
 ip6_finish_output+0x38/0x1f0 net/ipv6/ip6_output.c:152
 NF_HOOK_COND include/linux/netfilter.h:294 [inline]
 ip6_output+0x235/0x7f0 net/ipv6/ip6_output.c:175
 dst_output include/net/dst.h:433 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip6_xmit+0xe35/0x20b0 net/ipv6/ip6_output.c:279
 sctp_v6_xmit+0x313/0x660 net/sctp/ipv6.c:217
 sctp_packet_transmit+0x1ba5/0x36c0 net/sctp/output.c:626
 sctp_outq_flush_transports net/sctp/outqueue.c:1146 [inline]
 sctp_outq_flush+0x2b8/0x2780 net/sctp/outqueue.c:1194
 sctp_outq_uncork+0x6c/0x80 net/sctp/outqueue.c:757
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1781 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1184 [inline]
 sctp_do_sm+0x504/0x5190 net/sctp/sm_sideeffect.c:1155
 sctp_assoc_bh_rcv+0x343/0x660 net/sctp/associola.c:1059
 sctp_inq_push+0x1e4/0x280 net/sctp/inqueue.c:80
 sctp_backlog_rcv+0x196/0xbe0 net/sctp/input.c:339
 sk_backlog_rcv include/net/sock.h:945 [inline]
 __release_sock+0x129/0x390 net/core/sock.c:2412
 release_sock+0x59/0x1c0 net/core/sock.c:2928
 sctp_wait_for_connect+0x316/0x540 net/sctp/socket.c:9039
 __sctp_connect+0xab2/0xcd0 net/sctp/socket.c:1226
 __sctp_setsockopt_connectx+0x133/0x1a0 net/sctp/socket.c:1334
 sctp_setsockopt_connectx_old net/sctp/socket.c:1350 [inline]
 sctp_setsockopt net/sctp/socket.c:4644 [inline]
 sctp_setsockopt+0x22c0/0x6d10 net/sctp/socket.c:4608
 sock_common_setsockopt+0x94/0xd0 net/core/sock.c:3124
 __sys_setsockopt+0x17a/0x280 net/socket.c:2072
 __do_sys_setsockopt net/socket.c:2083 [inline]
 __se_sys_setsockopt net/socket.c:2080 [inline]
 __x64_sys_setsockopt+0xbe/0x150 net/socket.c:2080
 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4592c9
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f7f84505c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000004592c9
RDX: 000000000000006b RSI: 0000000000000084 RDI: 0000000000000005
RBP: 000000000075bf20 R08: 000000000000001c R09: 0000000000000000
R10: 000000002055bfe4 R11: 0000000000000246 R12: 00007f7f845066d4
R13: 00000000004ced98 R14: 00000000004dd4f0 R15: 00000000ffffffff

Allocated by task 3941:
 save_stack+0x23/0x90 mm/kasan/common.c:71
 set_track mm/kasan/common.c:79 [inline]
 __kasan_kmalloc mm/kasan/common.c:489 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462
 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:497
 slab_post_alloc_hook mm/slab.h:437 [inline]
 slab_alloc mm/slab.c:3326 [inline]
 kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3488
 dst_alloc+0x10e/0x200 net/core/dst.c:93
 ip6_dst_alloc+0x34/0xa0 net/ipv6/route.c:352
 ip6_rt_pcpu_alloc net/ipv6/route.c:1376 [inline]
 rt6_make_pcpu_route net/ipv6/route.c:1405 [inline]
 ip6_pol_route+0x536/0xe40 net/ipv6/route.c:2254
 ip6_pol_route_output+0x54/0x70 net/ipv6/route.c:2427
 __fib6_rule_action net/ipv6/fib6_rules.c:230 [inline]
 fib6_rule_action+0x49c/0xb40 net/ipv6/fib6_rules.c:261
 fib_rules_lookup+0x34c/0xa90 net/core/fib_rules.c:304
 fib6_rule_lookup+0x384/0x5a0 net/ipv6/fib6_rules.c:108
 ip6_route_output_flags+0x2c4/0x350 net/ipv6/route.c:2456
 ip6_route_output include/net/ip6_route.h:93 [inline]
 ip6_dst_lookup_tail+0xd1f/0x1f90 net/ipv6/ip6_output.c:1022
 ip6_dst_lookup_flow+0xa8/0x220 net/ipv6/ip6_output.c:1150
 sctp_v6_get_dst+0x785/0x1ce0 net/sctp/ipv6.c:278
 sctp_transport_route+0x12d/0x360 net/sctp/transport.c:297
 sctp_assoc_add_peer+0x53e/0xfc0 net/sctp/associola.c:663
 sctp_process_param net/sctp/sm_make_chunk.c:2522 [inline]
 sctp_process_init+0x2458/0x2ad0 net/sctp/sm_make_chunk.c:2343
 sctp_sf_do_5_1B_init+0x8ba/0xe50 net/sctp/sm_statefuns.c:401
 sctp_do_sm+0x121/0x5190 net/sctp/sm_sideeffect.c:1152
 sctp_endpoint_bh_rcv+0x451/0x950 net/sctp/endpointola.c:443
 sctp_inq_push+0x1e4/0x280 net/sctp/inqueue.c:80
 sctp_rcv+0x2807/0x35c0 net/sctp/input.c:256
 sctp6_rcv+0x17/0x30 net/sctp/ipv6.c:1049
 ip6_protocol_deliver_rcu+0x2fe/0x16c0 net/ipv6/ip6_input.c:397
 ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:438
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip6_input+0xe4/0x3f0 net/ipv6/ip6_input.c:447
 dst_input include/net/dst.h:439 [inline]
 ip6_rcv_finish+0x1de/0x310 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ipv6_rcv+0x10e/0x420 net/ipv6/ip6_input.c:272
 __netif_receive_skb_one_core+0x113/0x1a0 net/core/dev.c:4981
 __netif_receive_skb+0x2c/0x1d0 net/core/dev.c:5095
 process_backlog+0x206/0x750 net/core/dev.c:5906
 napi_poll net/core/dev.c:6329 [inline]
 net_rx_action+0x4f5/0x1070 net/core/dev.c:6395
 __do_softirq+0x25c/0x94c kernel/softirq.c:293

Freed by task 3880:
 save_stack+0x23/0x90 mm/kasan/common.c:71
 set_track mm/kasan/common.c:79 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459
 __cache_free mm/slab.c:3432 [inline]
 kmem_cache_free+0x86/0x260 mm/slab.c:3698
 dst_destroy+0x29e/0x3c0 net/core/dst.c:129
 dst_destroy_rcu+0x16/0x19 net/core/dst.c:142
 __rcu_reclaim kernel/rcu/rcu.h:222 [inline]
 rcu_do_batch kernel/rcu/tree.c:2092 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2310 [inline]
 rcu_core+0xba5/0x1500 kernel/rcu/tree.c:2291
 __do_softirq+0x25c/0x94c kernel/softirq.c:293

The buggy address belongs to the object at ffff88809aca7680
 which belongs to the cache ip6_dst_cache of size 224
The buggy address is located 4 bytes to the right of
 224-byte region [ffff88809aca7680, ffff88809aca7760)
The buggy address belongs to the page:
page:ffffea00026b29c0 refcount:1 mapcount:0 mapping:ffff8880a3049340 index:0x0
flags: 0x1fffc0000000200(slab)
raw: 01fffc0000000200 ffffea000256f808 ffffea0002220ac8 ffff8880a3049340
raw: 0000000000000000 ffff88809aca7040 000000010000000c 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809aca7600: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88809aca7680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88809aca7700: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
                                                       ^
 ffff88809aca7780: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
 ffff88809aca7800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================