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BUG: KASAN: use-after-free in __xfrm_policy_eval_candidates net/xfrm/xfrm_policy.c:2019 [inline]
BUG: KASAN: use-after-free in xfrm_policy_eval_candidates net/xfrm/xfrm_policy.c:2053 [inline]
BUG: KASAN: use-after-free in xfrm_policy_lookup_bytype+0xe52/0xe70 net/xfrm/xfrm_policy.c:2113
Read of size 4 at addr ffff88808ef25bb4 by task syz-executor4/3758

CPU: 0 PID: 3758 Comm: syz-executor4 Not tainted 4.20.0+ #362
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+0x1d3/0x2c6 lib/dump_stack.c:113
 print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432
 __xfrm_policy_eval_candidates net/xfrm/xfrm_policy.c:2019 [inline]
 xfrm_policy_eval_candidates net/xfrm/xfrm_policy.c:2053 [inline]
 xfrm_policy_lookup_bytype+0xe52/0xe70 net/xfrm/xfrm_policy.c:2113
 xfrm_policy_lookup+0x7e/0x80 net/xfrm/xfrm_policy.c:2145
 __xfrm_policy_check+0x14f0/0x2c40 net/xfrm/xfrm_policy.c:3354
 __xfrm_policy_check2 include/net/xfrm.h:1170 [inline]
 xfrm_policy_check include/net/xfrm.h:1175 [inline]
 sctp_rcv+0x27f4/0x4150 net/sctp/input.c:217
 sctp6_rcv+0x15/0x30 net/sctp/ipv6.c:1065
 ip6_protocol_deliver_rcu+0x372/0x1940 net/ipv6/ip6_input.c:394
 ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:434
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ip6_input+0xe9/0x600 net/ipv6/ip6_input.c:443
 dst_input include/net/dst.h:450 [inline]
 ip6_rcv_finish+0x17a/0x330 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ipv6_rcv+0x115/0x640 net/ipv6/ip6_input.c:272
 __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4973
 __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5083
 process_backlog+0x217/0x760 net/core/dev.c:5923
 napi_poll net/core/dev.c:6346 [inline]
 net_rx_action+0x7c5/0x1950 net/core/dev.c:6412
 __do_softirq+0x30c/0xb2e kernel/softirq.c:292
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027
 </IRQ>
 do_softirq.part.13+0x126/0x160 kernel/softirq.c:337
 do_softirq kernel/softirq.c:329 [inline]
 __local_bh_enable_ip+0x21d/0x260 kernel/softirq.c:189
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:696 [inline]
 ip6_finish_output2+0xcef/0x2930 net/ipv6/ip6_output.c:121
 ip6_finish_output+0x583/0xc50 net/ipv6/ip6_output.c:154
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip6_output+0x232/0x9d0 net/ipv6/ip6_output.c:171
 dst_output include/net/dst.h:444 [inline]
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ip6_xmit+0xf0d/0x24c0 net/ipv6/ip6_output.c:275
 sctp_v6_xmit+0x385/0x760 net/sctp/ipv6.c:234
 sctp_packet_transmit+0x1f05/0x3cd0 net/sctp/output.c:641
 sctp_packet_singleton net/sctp/outqueue.c:787 [inline]
 sctp_outq_flush_ctrl.constprop.11+0x7a9/0xe50 net/sctp/outqueue.c:918
 sctp_outq_flush+0x310/0x34f0 net/sctp/outqueue.c:1200
 sctp_outq_uncork+0x6a/0x80 net/sctp/outqueue.c:772
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1820 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1220 [inline]
 sctp_do_sm+0x5ff/0x7190 net/sctp/sm_sideeffect.c:1191
 sctp_primitive_ASSOCIATE+0x9d/0xd0 net/sctp/primitive.c:88
 __sctp_connect+0x9aa/0xda0 net/sctp/socket.c:1226
 __sctp_setsockopt_connectx+0x134/0x190 net/sctp/socket.c:1349
 sctp_setsockopt_connectx_old net/sctp/socket.c:1365 [inline]
 sctp_setsockopt+0x2109/0x7380 net/sctp/socket.c:4380
 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2986
 __sys_setsockopt+0x1ba/0x3c0 net/socket.c:1902
 __do_sys_setsockopt net/socket.c:1913 [inline]
 __se_sys_setsockopt net/socket.c:1910 [inline]
 __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1910
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4579b9
Code: fd b3 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 b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f7781224c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000004579b9
RDX: 000000000000006b RSI: 0000000000000084 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 000000000000001c R09: 0000000000000000
R10: 000000002055bfe4 R11: 0000000000000246 R12: 00007f77812256d4
R13: 00000000004cc370 R14: 00000000004d9810 R15: 00000000ffffffff

Allocated by task 7851:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553
 kmem_cache_alloc_trace+0x152/0x750 mm/slab.c:3620
 kmalloc include/linux/slab.h:546 [inline]
 syslog_print kernel/printk/printk.c:1302 [inline]
 do_syslog+0xbd7/0x1790 kernel/printk/printk.c:1475
 kmsg_read+0x8f/0xc0 fs/proc/kmsg.c:40
 proc_reg_read+0x2a3/0x3d0 fs/proc/inode.c:231
 __vfs_read+0x117/0x9b0 fs/read_write.c:416
 vfs_read+0x17f/0x3c0 fs/read_write.c:452
 ksys_read+0x101/0x260 fs/read_write.c:578
 __do_sys_read fs/read_write.c:588 [inline]
 __se_sys_read fs/read_write.c:586 [inline]
 __x64_sys_read+0x73/0xb0 fs/read_write.c:586
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 7851:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xcf/0x230 mm/slab.c:3817
 syslog_print kernel/printk/printk.c:1361 [inline]
 do_syslog+0x1572/0x1790 kernel/printk/printk.c:1475
 kmsg_read+0x8f/0xc0 fs/proc/kmsg.c:40
 proc_reg_read+0x2a3/0x3d0 fs/proc/inode.c:231
 __vfs_read+0x117/0x9b0 fs/read_write.c:416
 vfs_read+0x17f/0x3c0 fs/read_write.c:452
 ksys_read+0x101/0x260 fs/read_write.c:578
 __do_sys_read fs/read_write.c:588 [inline]
 __se_sys_read fs/read_write.c:586 [inline]
 __x64_sys_read+0x73/0xb0 fs/read_write.c:586
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff88808ef25b00
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 180 bytes inside of
 1024-byte region [ffff88808ef25b00, ffff88808ef25f00)
The buggy address belongs to the page:
page:ffffea00023bc900 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0xffff88808ef25680 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea0002394188 ffffea00021c8f88 ffff88812c3f0ac0
raw: ffff88808ef25680 ffff88808ef24000 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88808ef25a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88808ef25b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88808ef25b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff88808ef25c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808ef25c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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