==================================================================
BUG: KASAN: slab-out-of-bounds in fl6_update_dst+0x2bb/0x2c0 net/ipv6/exthdrs.c:1356
Read of size 16 at addr ffff8880a7decf78 by task syz-executor.5/29419

CPU: 0 PID: 29419 Comm: syz-executor.5 Not tainted 5.7.0-syzkaller #0
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+0x188/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd3/0x413 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 fl6_update_dst+0x2bb/0x2c0 net/ipv6/exthdrs.c:1356
 dccp_v6_send_response+0x361/0xb90 net/dccp/ipv6.c:210
 dccp_v6_conn_request+0xcb2/0x1670 net/dccp/ipv6.c:382
 dccp_rcv_state_process+0x603/0x18b4 net/dccp/input.c:609
 dccp_v6_do_rcv+0x264/0xb70 net/dccp/ipv6.c:638
 sk_backlog_rcv include/net/sock.h:996 [inline]
 __sk_receive_skb+0x323/0xc80 net/core/sock.c:519
 dccp_v6_rcv+0xe9c/0x1ce8 net/dccp/ipv6.c:775
 ip6_protocol_deliver_rcu+0x2e6/0x1660 net/ipv6/ip6_input.c:433
 ip6_input_finish+0x7f/0x160 net/ipv6/ip6_input.c:474
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ip6_input+0xcf/0x3d0 net/ipv6/ip6_input.c:483
 dst_input include/net/dst.h:441 [inline]
 ip6_rcv_finish+0x1d9/0x310 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ipv6_rcv+0xf8/0x3f0 net/ipv6/ip6_input.c:307
 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5268
 __netif_receive_skb+0x27/0x1c0 net/core/dev.c:5382
 process_backlog+0x21e/0x7a0 net/core/dev.c:6226
 napi_poll net/core/dev.c:6671 [inline]
 net_rx_action+0x4c2/0x1070 net/core/dev.c:6739
 __do_softirq+0x26c/0x9f7 kernel/softirq.c:292
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082
 </IRQ>
 do_softirq.part.0+0x10f/0x160 kernel/softirq.c:337
 do_softirq kernel/softirq.c:329 [inline]
 __local_bh_enable_ip+0x20e/0x270 kernel/softirq.c:189
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:723 [inline]
 ip6_finish_output2+0x10f8/0x25b0 net/ipv6/ip6_output.c:118
 __ip6_finish_output+0x442/0xab0 net/ipv6/ip6_output.c:143
 ip6_finish_output+0x34/0x1f0 net/ipv6/ip6_output.c:153
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x239/0x810 net/ipv6/ip6_output.c:176
 dst_output include/net/dst.h:435 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ip6_xmit+0xe1a/0x2090 net/ipv6/ip6_output.c:280
 inet6_csk_xmit+0x339/0x610 net/ipv6/inet6_connection_sock.c:135
 dccp_transmit_skb+0x968/0x12d0 net/dccp/output.c:138
 dccp_connect+0x31b/0x610 net/dccp/output.c:560
 dccp_v6_connect+0xc1e/0x19d0 net/dccp/ipv6.c:947
 __inet_stream_connect+0x80f/0xe30 net/ipv4/af_inet.c:658
 inet_stream_connect+0x53/0xa0 net/ipv4/af_inet.c:722
 __sys_connect_file+0x155/0x1a0 net/socket.c:1854
 __sys_connect+0x160/0x190 net/socket.c:1871
 __do_sys_connect net/socket.c:1882 [inline]
 __se_sys_connect net/socket.c:1879 [inline]
 __x64_sys_connect+0x6f/0xb0 net/socket.c:1879
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca69
Code: 0d 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 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f679647ec78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00000000004db160 RCX: 000000000045ca69
RDX: 000000000000001b RSI: 0000000020419000 RDI: 0000000000000004
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000084 R14: 00000000004c3402 R15: 00007f679647f6d4

Allocated by task 29419:
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc mm/kasan/common.c:494 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:467
 __do_kmalloc mm/slab.c:3656 [inline]
 __kmalloc+0x161/0x7a0 mm/slab.c:3665
 kmalloc include/linux/slab.h:560 [inline]
 sock_kmalloc net/core/sock.c:2255 [inline]
 sock_kmalloc+0xb5/0x100 net/core/sock.c:2246
 ipv6_renew_options+0x274/0x940 net/ipv6/exthdrs.c:1275
 do_ipv6_setsockopt.isra.0+0x2db4/0x4330 net/ipv6/ipv6_sockglue.c:471
 ipv6_setsockopt+0xfb/0x180 net/ipv6/ipv6_sockglue.c:900
 dccp_setsockopt net/dccp/proto.c:570 [inline]
 dccp_setsockopt+0x89/0xd0 net/dccp/proto.c:566
 __sys_setsockopt+0x248/0x480 net/socket.c:2127
 __do_sys_setsockopt net/socket.c:2143 [inline]
 __se_sys_setsockopt net/socket.c:2140 [inline]
 __x64_sys_setsockopt+0xba/0x150 net/socket.c:2140
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

Freed by task 8040:
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 kasan_set_free_info mm/kasan/common.c:316 [inline]
 __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:455
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x109/0x2b0 mm/slab.c:3757
 nf_conntrack_free+0x88/0xe0 net/netfilter/nf_conntrack_core.c:1557
 destroy_conntrack+0x19b/0x270 net/netfilter/nf_conntrack_core.c:628
 nf_conntrack_destroy+0xe7/0x230 net/netfilter/core.c:600
 nf_conntrack_put include/linux/netfilter/nf_conntrack_common.h:34 [inline]
 nf_conntrack_put include/linux/netfilter/nf_conntrack_common.h:31 [inline]
 nf_ct_put include/net/netfilter/nf_conntrack.h:162 [inline]
 nf_ct_gc_expired net/netfilter/nf_conntrack_core.c:722 [inline]
 nf_ct_gc_expired+0x1c6/0x330 net/netfilter/nf_conntrack_core.c:714
 gc_worker+0x9cc/0xd40 net/netfilter/nf_conntrack_core.c:1401
 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268
 worker_thread+0x96/0xe20 kernel/workqueue.c:2414
 kthread+0x388/0x470 kernel/kthread.c:268
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351

The buggy address belongs to the object at ffff8880a7decf00
 which belongs to the cache kmalloc-128 of size 128
The buggy address is located 120 bytes inside of
 128-byte region [ffff8880a7decf00, ffff8880a7decf80)
The buggy address belongs to the page:
page:ffffea00029f7b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea00026e1988 ffffea00028ff248 ffff8880aa000700
raw: 0000000000000000 ffff8880a7dec000 0000000100000010 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a7dece00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880a7dece80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880a7decf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc
                                                                ^
 ffff8880a7decf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a7ded000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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