==================================================================
BUG: KASAN: use-after-free in decode_session6 net/xfrm/xfrm_policy.c:3394 [inline]
BUG: KASAN: use-after-free in __xfrm_decode_session+0x1cfb/0x2e90 net/xfrm/xfrm_policy.c:3486
Read of size 1 at addr ffff8880a5740ff8 by task syz-executor.4/11106

CPU: 1 PID: 11106 Comm: syz-executor.4 Not tainted 5.7.0-rc5-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:382
 __kasan_report.cold+0x20/0x38 mm/kasan/report.c:511
 kasan_report+0x33/0x50 mm/kasan/common.c:625
 decode_session6 net/xfrm/xfrm_policy.c:3394 [inline]
 __xfrm_decode_session+0x1cfb/0x2e90 net/xfrm/xfrm_policy.c:3486
 xfrm_decode_session include/net/xfrm.h:1138 [inline]
 vti_tunnel_xmit+0x25c/0x19a0 net/ipv4/ip_vti.c:300
 __netdev_start_xmit include/linux/netdevice.h:4605 [inline]
 netdev_start_xmit include/linux/netdevice.h:4619 [inline]
 xmit_one net/core/dev.c:3545 [inline]
 dev_hard_start_xmit+0x1a4/0x9b0 net/core/dev.c:3561
 sch_direct_xmit+0x345/0xc20 net/sched/sch_generic.c:313
 qdisc_restart net/sched/sch_generic.c:376 [inline]
 __qdisc_run+0x4d1/0x17b0 net/sched/sch_generic.c:384
 __dev_xmit_skb net/core/dev.c:3784 [inline]
 __dev_queue_xmit+0x165b/0x3090 net/core/dev.c:4089
 neigh_output include/net/neighbour.h:510 [inline]
 ip6_finish_output2+0x1091/0x25b0 net/ipv6/ip6_output.c:117
 __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]
 mld_sendpack+0x961/0xdf0 net/ipv6/mcast.c:1679
 mld_send_cr net/ipv6/mcast.c:1975 [inline]
 mld_ifc_timer_expire+0x42e/0x920 net/ipv6/mcast.c:2474
 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x623/0x1600 kernel/time/timer.c:1786
 __do_softirq+0x26c/0x9f7 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x192/0x1d0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:546 [inline]
 smp_apic_timer_interrupt+0x19e/0x600 arch/x86/kernel/apic/apic.c:1140
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x4b/0x80 kernel/locking/spinlock.c:199
Code: c0 70 c0 94 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 31 48 83 3d 1e f7 be 01 00 74 25 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 eb 3f 79 f9 65 8b 05 5c 55 2c 78 85 c0 74 02 5d
RSP: 0018:ffffc90001976a10 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff132980e RBX: ffff888099426340 RCX: 1ffffffff1861c9a
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff888099426c04
RBP: ffff8880ae737c80 R08: 0000000000000001 R09: fffffbfff1860738
R10: ffffffff8c3039bf R11: fffffbfff1860737 R12: ffff8880ae737c80
R13: ffff888068998300 R14: 0000000000000000 R15: 0000000000000001
 finish_lock_switch kernel/sched/core.c:3105 [inline]
 finish_task_switch+0x147/0x750 kernel/sched/core.c:3205
 context_switch kernel/sched/core.c:3369 [inline]
 __schedule+0x93f/0x1ff0 kernel/sched/core.c:4082
 preempt_schedule_irq+0xb0/0x150 kernel/sched/core.c:4340
 retint_kernel+0x1b/0x2b
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:759 [inline]
RIP: 0010:kfree+0x1fe/0x2b0 mm/slab.c:3758
Code: 75 6b 48 83 3d 62 6f e3 07 00 0f 85 4e ff ff ff 0f 0b e8 e5 61 c7 ff 48 83 3d 4d 6f e3 07 00 0f 84 b3 00 00 00 48 89 df 57 9d <0f> 1f 44 00 00 5b 5d 41 5c 41 5d c3 65 ff 05 97 cd 50 7e 48 8b 05
RSP: 0018:ffffc90001976c28 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000007 RBX: 0000000000000286 RCX: 1ffffffff1861c9a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000286
RBP: ffff888098556000 R08: 0000000000000001 R09: fffffbfff1860738
R10: ffffffff8c3039bf R11: fffffbfff1860737 R12: ffff8880aa000e00
R13: ffffffff861be46b R14: 0000000000000000 R15: ffff8880985566c0
 skb_free_head+0x8b/0xa0 net/core/skbuff.c:590
 skb_release_data+0x42e/0x8b0 net/core/skbuff.c:610
 skb_release_all+0x46/0x60 net/core/skbuff.c:664
 __kfree_skb net/core/skbuff.c:678 [inline]
 consume_skb net/core/skbuff.c:837 [inline]
 consume_skb+0xf3/0x400 net/core/skbuff.c:831
 netlink_broadcast_filtered+0x34f/0xd40 net/netlink/af_netlink.c:1513
 netlink_broadcast net/netlink/af_netlink.c:1535 [inline]
 nlmsg_multicast include/net/netlink.h:1020 [inline]
 nlmsg_notify+0x90/0x250 net/netlink/af_netlink.c:2512
 rtnl_notify net/core/rtnetlink.c:737 [inline]
 rtmsg_ifinfo_send net/core/rtnetlink.c:3726 [inline]
 rtmsg_ifinfo_event.part.0+0xb6/0xe0 net/core/rtnetlink.c:3741
 rtmsg_ifinfo_event net/core/rtnetlink.c:3749 [inline]
 rtmsg_ifinfo+0x7f/0xa0 net/core/rtnetlink.c:3747
 netdev_state_change net/core/dev.c:1453 [inline]
 netdev_state_change+0x121/0x140 net/core/dev.c:1444
 do_setlink+0x2dde/0x3680 net/core/rtnetlink.c:2835
 rtnl_group_changelink net/core/rtnetlink.c:3124 [inline]
 __rtnl_newlink+0xc96/0x1590 net/core/rtnetlink.c:3278
 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3398
 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5461
 netlink_rcv_skb+0x15a/0x410 net/netlink/af_netlink.c:2469
 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
 netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329
 netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 ____sys_sendmsg+0x6e6/0x810 net/socket.c:2352
 ___sys_sendmsg+0x100/0x170 net/socket.c:2406
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2439
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca29
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:00007ff96a680c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000500f40 RCX: 000000000045ca29
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000004
RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000a04 R14: 00000000004ccdcc R15: 00007ff96a6816d4

Allocated by task 10857:
 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
 slab_post_alloc_hook mm/slab.h:586 [inline]
 slab_alloc mm/slab.c:3320 [inline]
 kmem_cache_alloc+0x11b/0x740 mm/slab.c:3484
 getname_flags fs/namei.c:138 [inline]
 getname_flags+0xd2/0x5b0 fs/namei.c:128
 do_sys_openat2+0x3fc/0x7d0 fs/open.c:1142
 do_sys_open+0xc3/0x140 fs/open.c:1164
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

Freed by task 10857:
 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]
 kmem_cache_free+0x7f/0x320 mm/slab.c:3694
 putname+0xe1/0x120 fs/namei.c:259
 do_sys_openat2+0x467/0x7d0 fs/open.c:1157
 do_sys_open+0xc3/0x140 fs/open.c:1164
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

The buggy address belongs to the object at ffff8880a5740d80
 which belongs to the cache names_cache of size 4096
The buggy address is located 632 bytes inside of
 4096-byte region [ffff8880a5740d80, ffff8880a5741d80)
The buggy address belongs to the page:
page:ffffea000295d000 refcount:1 mapcount:0 mapping:00000000cb9d5c10 index:0x0 head:ffffea000295d000 order:1 compound_mapcount:0
flags: 0xfffe0000010200(slab|head)
raw: 00fffe0000010200 ffffea0001670c08 ffffea00027a8f88 ffff8880aa1ec000
raw: 0000000000000000 ffff8880a5740d80 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a5740e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880a5740f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880a5740f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                                ^
 ffff8880a5741000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880a5741080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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