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BUG: KASAN: slab-out-of-bounds in fl6_update_dst+0x2bb/0x2c0 net/ipv6/exthdrs.c:1356
Read of size 16 at addr ffff88809ed65cd8 by task syz-executor.3/9215

CPU: 0 PID: 9215 Comm: syz-executor.3 Not tainted 5.7.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __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:382
 __kasan_report.cold+0x20/0x38 mm/kasan/report.c:511
 kasan_report+0x33/0x50 mm/kasan/common.c:625
 fl6_update_dst+0x2bb/0x2c0 net/ipv6/exthdrs.c:1356
 sctp_v6_get_dst+0x5e7/0x1c30 net/sctp/ipv6.c:276
 sctp_transport_route+0x125/0x350 net/sctp/transport.c:297
 sctp_assoc_add_peer+0x5a0/0x1030 net/sctp/associola.c:659
 sctp_process_param net/sctp/sm_make_chunk.c:2527 [inline]
 sctp_process_init+0x23eb/0x2a50 net/sctp/sm_make_chunk.c:2348
 sctp_sf_do_unexpected_init net/sctp/sm_statefuns.c:1551 [inline]
 sctp_sf_do_unexpected_init.isra.0+0x797/0x12a0 net/sctp/sm_statefuns.c:1451
 sctp_do_sm+0x116/0x4eb0 net/sctp/sm_sideeffect.c:1153
 sctp_assoc_bh_rcv+0x386/0x6d0 net/sctp/associola.c:1044
 sctp_inq_push+0x1da/0x270 net/sctp/inqueue.c:80
 sctp_backlog_rcv+0x1f3/0x1290 net/sctp/input.c:344
 sk_backlog_rcv include/net/sock.h:996 [inline]
 __release_sock+0x134/0x3a0 net/core/sock.c:2459
 release_sock+0x54/0x1b0 net/core/sock.c:2975
 sctp_wait_for_connect+0x300/0x530 net/sctp/socket.c:9295
 __sctp_connect+0x9d2/0xc70 net/sctp/socket.c:1240
 sctp_connect net/sctp/socket.c:4908 [inline]
 sctp_inet_connect+0x14b/0x1b0 net/sctp/socket.c:4923
 __sys_connect_file+0x155/0x1a0 net/socket.c:1859
 __sys_connect+0x160/0x190 net/socket.c:1876
 __do_sys_connect net/socket.c:1887 [inline]
 __se_sys_connect net/socket.c:1884 [inline]
 __ia32_sys_connect+0x6e/0xb0 net/socket.c:1884
 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline]
 do_fast_syscall_32+0x270/0xe90 arch/x86/entry/common.c:396
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139

Allocated by task 9215:
 save_stack+0x1b/0x40 mm/kasan/common.c:49
 set_track mm/kasan/common.c:57 [inline]
 __kasan_kmalloc mm/kasan/common.c:495 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:468
 __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:2166 [inline]
 sock_kmalloc+0xb5/0x100 net/core/sock.c:2157
 ipv6_renew_options+0x274/0x940 net/ipv6/exthdrs.c:1275
 do_ipv6_setsockopt.isra.0+0x2eaf/0x42f0 net/ipv6/ipv6_sockglue.c:435
 ipv6_setsockopt+0xfb/0x180 net/ipv6/ipv6_sockglue.c:949
 sctp_setsockopt+0x13e/0x7090 net/sctp/socket.c:4685
 compat_sock_common_setsockopt+0xf6/0x120 net/core/sock.c:3184
 __compat_sys_setsockopt+0x15d/0x310 net/compat.c:400
 __do_compat_sys_setsockopt net/compat.c:413 [inline]
 __se_compat_sys_setsockopt net/compat.c:410 [inline]
 __ia32_compat_sys_setsockopt+0xb9/0x150 net/compat.c:410
 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline]
 do_fast_syscall_32+0x270/0xe90 arch/x86/entry/common.c:396
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139

Freed by task 8765:
 save_stack+0x1b/0x40 mm/kasan/common.c:49
 set_track mm/kasan/common.c:57 [inline]
 kasan_set_free_info mm/kasan/common.c:317 [inline]
 __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:456
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x109/0x2b0 mm/slab.c:3757
 ip_dst_metrics_put include/net/ip.h:491 [inline]
 ip6_dst_destroy+0x20d/0x280 net/ipv6/route.c:373
 dst_destroy+0x108/0x3a0 net/core/dst.c:120
 rcu_do_batch kernel/rcu/tree.c:2206 [inline]
 rcu_core+0x59f/0x1370 kernel/rcu/tree.c:2433
 __do_softirq+0x26c/0x9f7 kernel/softirq.c:292

The buggy address belongs to the object at ffff88809ed65c80
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 88 bytes inside of
 96-byte region [ffff88809ed65c80, ffff88809ed65ce0)
The buggy address belongs to the page:
page:ffffea00027b5940 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea0002498508 ffffea000242d408 ffff8880aa000540
raw: 0000000000000000 ffff88809ed65000 0000000100000020 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809ed65b80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff88809ed65c00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff88809ed65c80: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
                                                    ^
 ffff88809ed65d00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff88809ed65d80: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
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