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BUG: KMSAN: use-after-free in rt6_uncached_list_del net/ipv6/route.c:152 [inline]
BUG: KMSAN: use-after-free in ip6_dst_destroy+0x5d8/0x720 net/ipv6/route.c:374
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.0-rc2-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+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 rt6_uncached_list_del net/ipv6/route.c:152 [inline]
 ip6_dst_destroy+0x5d8/0x720 net/ipv6/route.c:374
 dst_destroy+0x1f5/0x5c0 net/core/dst.c:120
 dst_destroy_rcu+0x46/0x50 net/core/dst.c:142
 rcu_do_batch kernel/rcu/tree.c:2186 [inline]
 rcu_core+0xb8a/0x19f0 kernel/rcu/tree.c:2410
 rcu_core_si+0xe/0x10 kernel/rcu/tree.c:2419
 __do_softirq+0x311/0x83d kernel/softirq.c:293
 invoke_softirq kernel/softirq.c:375 [inline]
 irq_exit+0x230/0x280 kernel/softirq.c:416
 exiting_irq+0xe/0x10 arch/x86/include/asm/apic.h:546
 smp_apic_timer_interrupt+0x48/0x70 arch/x86/kernel/apic/apic.c:1149
 apic_timer_interrupt+0x2e/0x40 arch/x86/entry/entry_64.S:834
 </IRQ>
RIP: 0010:default_idle+0x53/0x90 arch/x86/kernel/process.c:696
Code: c3 f4 c9 f2 44 8b 35 44 c6 bf 01 48 c7 c7 98 87 97 b7 e8 60 e5 96 f3 83 38 00 75 31 45 85 f6 7e 07 0f 00 2d 67 9f 49 00 fb f4 <65> 8b 35 ce 61 29 4a c7 03 00 00 00 00 c7 43 08 00 00 00 00 bf ff
RSP: 0018:ffffffffb6e03d88 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: ffffa1614e16b798 RBX: ffffffffb6e2cc90 RCX: ffffe34dc7cdf580
RDX: ffffa1613e35e798 RSI: 0000000000000000 RDI: ffffffffb7978798
RBP: ffffffffb6e03d98 R08: ffffe34dc000000f R09: ffffa1606fffb000
R10: 0000000000000004 R11: ffffffffb5d7c120 R12: ffffffffb6e2c2c0
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffffb6e2cc90
 arch_cpu_idle+0x25/0x30 arch/x86/kernel/process.c:686
 default_idle_call kernel/sched/idle.c:94 [inline]
 cpuidle_idle_call kernel/sched/idle.c:154 [inline]
 do_idle+0x26c/0x7b0 kernel/sched/idle.c:269
 cpu_startup_entry+0x45/0x50 kernel/sched/idle.c:361
 rest_init+0x1be/0x1f0 init/main.c:655
 arch_call_rest_init+0x13/0x15
 start_kernel+0xa45/0xc1b init/main.c:995
 x86_64_start_reservations+0x18/0x28 arch/x86/kernel/head64.c:490
 x86_64_start_kernel+0x83/0x86 arch/x86/kernel/head64.c:471
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127
 kmsan_slab_free+0x6e/0xb0 mm/kmsan/kmsan_hooks.c:107
 slab_free_freelist_hook mm/slub.c:1477 [inline]
 slab_free mm/slub.c:3040 [inline]
 kfree+0x565/0x30a0 mm/slub.c:3993
 __netdev_name_node_alt_destroy net/core/dev.c:322 [inline]
 netdev_name_node_alt_destroy+0x587/0x690 net/core/dev.c:334
 rtnl_alt_ifname net/core/rtnetlink.c:3518 [inline]
 rtnl_linkprop+0x939/0xc00 net/core/rtnetlink.c:3567
 rtnl_dellinkprop+0x9d/0xb0 net/core/rtnetlink.c:3588
 rtnetlink_rcv_msg+0x1153/0x1570 net/core/rtnetlink.c:5438
 netlink_rcv_skb+0x451/0x650 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5456
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0xf9e/0x1100 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x1246/0x14d0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 ____sys_sendmsg+0x12b6/0x1350 net/socket.c:2343
 ___sys_sendmsg net/socket.c:2397 [inline]
 __sys_sendmsg+0x451/0x5f0 net/socket.c:2430
 __do_sys_sendmsg net/socket.c:2439 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2437
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2437
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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