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BUG: KMSAN: uninit-value in rcu_cblist_dequeue+0x1f1/0x270 kernel/rcu/rcu_segcblist.c:54
CPU: 0 PID: 8 Comm: ksoftirqd/0 Not tainted 4.17.0+ #9
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+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:1125
 __msan_warning_32+0x70/0xc0 mm/kmsan/kmsan_instr.c:620
 rcu_cblist_dequeue+0x1f1/0x270 kernel/rcu/rcu_segcblist.c:54
 rcu_do_batch kernel/rcu/tree.c:2673 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2930 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2897 [inline]
 rcu_process_callbacks+0x19a7/0x2060 kernel/rcu/tree.c:2914
 __do_softirq+0x592/0x979 kernel/softirq.c:285
 run_ksoftirqd+0x1f/0x40 kernel/softirq.c:646
 smpboot_thread_fn+0x4ac/0x9a0 kernel/smpboot.c:164
 kthread+0x4db/0x6c0 kernel/kthread.c:241
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:413

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:282 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:297 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:689
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:464
 rcu_cblist_dequeue+0x216/0x270 kernel/rcu/rcu_segcblist.c:54
 rcu_do_batch kernel/rcu/tree.c:2673 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2930 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2897 [inline]
 rcu_process_callbacks+0x19a7/0x2060 kernel/rcu/tree.c:2914
 __do_softirq+0x592/0x979 kernel/softirq.c:285

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:282 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:297 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:689
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:464
 rcu_segcblist_enqueue+0x24c/0x2d0 kernel/rcu/rcu_segcblist.c:150
 __call_rcu+0x227/0xef0 kernel/rcu/tree.c:3057
 kfree_call_rcu+0x35/0x40 kernel/rcu/tree.c:3139
 __free_vmap_area+0x562/0x650 mm/vmalloc.c:585
 __purge_vmap_area_lazy+0x2c1/0x3b0 mm/vmalloc.c:702
 try_purge_vmap_area_lazy mm/vmalloc.c:717 [inline]
 free_vmap_area_noflush+0x1fa/0x230 mm/vmalloc.c:749
 free_unmap_vmap_area mm/vmalloc.c:759 [inline]
 remove_vm_area+0x3b9/0x460 mm/vmalloc.c:1504
 __vunmap+0xb0/0x3e0 mm/vmalloc.c:1522
 vfree+0x79/0x170 mm/vmalloc.c:1606
 snd_pcm_lib_free_vmalloc_buffer+0xba/0x170 sound/core/pcm_memory.c:433
 loopback_hw_free+0x1d9/0x270 sound/drivers/aloop.c:604
 snd_pcm_release_substream+0x673/0x990 sound/core/pcm_native.c:2356
 snd_pcm_oss_release_file sound/core/oss/pcm_oss.c:2382 [inline]
 snd_pcm_oss_release+0x30b/0x4c0 sound/core/oss/pcm_oss.c:2562
 __fput+0x458/0xa30 fs/file_table.c:209
 ____fput+0x37/0x40 fs/file_table.c:243
 task_work_run+0x22e/0x2b0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x110e/0x3930 kernel/exit.c:867
 do_group_exit+0x1a0/0x360 kernel/exit.c:970
 get_signal+0x1405/0x1ec0 kernel/signal.c:2482
 do_signal+0xb8/0x1d20 arch/x86/kernel/signal.c:810
 exit_to_usermode_loop arch/x86/entry/common.c:162 [inline]
 prepare_exit_to_usermode+0x271/0x3a0 arch/x86/entry/common.c:196
 syscall_return_slowpath+0xe9/0x710 arch/x86/entry/common.c:265
 do_syscall_64+0x1ad/0x230 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:282 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:192
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:318
 __kmalloc_node+0xe44/0x1200 mm/slub.c:3865
 kmalloc_node include/linux/slab.h:554 [inline]
 alloc_vmap_area+0x1e6/0x15a0 mm/vmalloc.c:419
 __get_vm_area_node+0x3a6/0x810 mm/vmalloc.c:1409
 __vmalloc_node_range+0x2a7/0x1170 mm/vmalloc.c:1754
 __vmalloc_node mm/vmalloc.c:1804 [inline]
 __vmalloc_node_flags mm/vmalloc.c:1818 [inline]
 vzalloc+0xd8/0xf0 mm/vmalloc.c:1857
 alloc_counters+0x99/0x910 net/ipv4/netfilter/ip_tables.c:802
 copy_entries_to_user net/ipv4/netfilter/ip_tables.c:824 [inline]
 get_entries net/ipv4/netfilter/ip_tables.c:1026 [inline]
 do_ipt_get_ctl+0x843/0x1120 net/ipv4/netfilter/ip_tables.c:1702
 nf_sockopt net/netfilter/nf_sockopt.c:104 [inline]
 nf_getsockopt+0x481/0x4e0 net/netfilter/nf_sockopt.c:122
 ip_getsockopt+0x284/0x3c0 net/ipv4/ip_sockglue.c:1562
 tcp_getsockopt+0x1c6/0x1f0 net/ipv4/tcp.c:3349
 sock_common_getsockopt+0x13f/0x180 net/core/sock.c:2998
 __sys_getsockopt+0x48c/0x550 net/socket.c:1940
 __do_sys_getsockopt net/socket.c:1951 [inline]
 __se_sys_getsockopt net/socket.c:1948 [inline]
 __x64_sys_getsockopt+0x15d/0x1c0 net/socket.c:1948
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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