syzbot

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BUG: KMSAN: uninit-value in pcpu_chunk_slot mm/percpu.c:226 [inline]
BUG: KMSAN: uninit-value in pcpu_free_area+0x139/0x19a0 mm/percpu.c:1028
CPU: 1 PID: 3580 Comm: syzkaller794187 Not tainted 4.16.0+ #83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 pcpu_chunk_slot mm/percpu.c:226 [inline]
 pcpu_free_area+0x139/0x19a0 mm/percpu.c:1028
 free_percpu+0x60f/0xb20 mm/percpu.c:1726
 xt_percpu_counter_free+0xd5/0x110 net/netfilter/x_tables.c:1768
 cleanup_entry+0x59b/0x5c0 net/ipv6/netfilter/ip6_tables.c:679
 __do_replace+0xd5e/0x1050 net/ipv6/netfilter/ip6_tables.c:1112
 do_replace net/ipv6/netfilter/ip6_tables.c:1168 [inline]
 do_ip6t_set_ctl+0x739/0x930 net/ipv6/netfilter/ip6_tables.c:1690
 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
 nf_setsockopt+0x476/0x4d0 net/netfilter/nf_sockopt.c:115
 ipv6_setsockopt+0x1e2/0x340 net/ipv6/ipv6_sockglue.c:927
 tcp_setsockopt+0x1bb/0x1f0 net/ipv4/tcp.c:2905
 sock_common_setsockopt+0x136/0x170 net/core/sock.c:2975
 SYSC_setsockopt+0x4b8/0x570 net/socket.c:1849
 SyS_setsockopt+0x76/0xa0 net/socket.c:1828
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x444fea
RSP: 002b:00007ffe9cea3848 EFLAGS: 00000206 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00000000006ceba0 RCX: 0000000000444fea
RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003
RBP: 00000000006ceba0 R08: 00000000000003b8 R09: 0000000000004000
R10: 00000000006ceb40 R11: 0000000000000206 R12: 00007ffe9cea3870
R13: 00000000006d0d60 R14: 0000000000000003 R15: 0000000000000029

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:293 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:521
 pcpu_free_area+0xb1b/0x19a0 mm/percpu.c:1039
 free_percpu+0x60f/0xb20 mm/percpu.c:1726
 packet_free_pending net/packet/af_packet.c:1226 [inline]
 packet_release+0x1410/0x15e0 net/packet/af_packet.c:3039
 sock_release net/socket.c:595 [inline]
 sock_close+0xe0/0x300 net/socket.c:1149
 __fput+0x49e/0xa10 fs/file_table.c:209
 ____fput+0x37/0x40 fs/file_table.c:243
 task_work_run+0x243/0x2c0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x10e1/0x38d0 kernel/exit.c:867
 do_group_exit+0x1a0/0x360 kernel/exit.c:970
 SYSC_exit_group+0x21/0x30 kernel/exit.c:981
 SyS_exit_group+0x25/0x30 kernel/exit.c:979
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
Local variable description: ----flags.i.i.i.i@_raw_spin_lock_irqsave
Variable was created at:
 _raw_spin_lock_irqsave+0x45/0xf0 kernel/locking/spinlock.c:150
 skb_dequeue net/core/skbuff.c:2801 [inline]
 skb_queue_purge+0x52/0x490 net/core/skbuff.c:2839
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