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BUG: KMSAN: uninit-value in rcu_cblist_dequeue+0x1fd/0x290 kernel/rcu/rcu_segcblist.c:55
CPU: 0 PID: 11631 Comm: udevd Not tainted 4.16.0+ #87
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __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:683
 rcu_cblist_dequeue+0x1fd/0x290 kernel/rcu/rcu_segcblist.c:55
 rcu_do_batch kernel/rcu/tree.c:2672 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2933 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2900 [inline]
 rcu_process_callbacks+0x17cf/0x2070 kernel/rcu/tree.c:2917
 __do_softirq+0x56d/0x93d kernel/softirq.c:285
 invoke_softirq kernel/softirq.c:365 [inline]
 irq_exit+0x202/0x240 kernel/softirq.c:405
 exiting_irq+0xe/0x10 arch/x86/include/asm/apic.h:541
 smp_apic_timer_interrupt+0x64/0x90 arch/x86/kernel/apic/apic.c:1055
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:857
 </IRQ>
RIP: 0010:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:66
RSP: 0018:ffff880185a0f128 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff12
RAX: ffff8801a7e2f2ff RBX: ffff880185a0f20d RCX: 0000000000000000
RDX: 0000000000000001 RSI: 00000000ffffffff RDI: ffff8801a7e2f20e
RBP: ffff880185a0f1d0 R08: 0000000001080020 R09: ffff8801a7e2f20d
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: ffffffff8aab5740 R14: 0000000000000001 R15: ffff880150048000
 page_remove_rmap+0xb5/0xe30 mm/rmap.c:1296
 zap_pte_range mm/memory.c:1337 [inline]
 zap_pmd_range mm/memory.c:1441 [inline]
 zap_pud_range mm/memory.c:1470 [inline]
 zap_p4d_range mm/memory.c:1491 [inline]
 unmap_page_range+0x1db4/0x3be0 mm/memory.c:1512
 unmap_single_vma+0x45b/0x5f0 mm/memory.c:1557
 unmap_vmas+0x1f4/0x360 mm/memory.c:1587
 exit_mmap+0x3da/0x950 mm/mmap.c:3020
 __mmput+0x16c/0x610 kernel/fork.c:961
 mmput+0xab/0xf0 kernel/fork.c:982
 exec_mmap fs/exec.c:1039 [inline]
 flush_old_exec+0x1adb/0x2170 fs/exec.c:1271
 load_elf_binary+0x134d/0x8f90 fs/binfmt_elf.c:864
 search_binary_handler+0x2ef/0xac0 fs/exec.c:1638
 exec_binprm fs/exec.c:1680 [inline]
 do_execveat_common+0x1f4d/0x2ce0 fs/exec.c:1802
 do_execve fs/exec.c:1847 [inline]
 SYSC_execve+0xe2/0x110 fs/exec.c:1928
 SyS_execve+0x56/0x80 fs/exec.c:1923
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x7f88796f9207
RSP: 002b:00007ffcf12606e8 EFLAGS: 00000206 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f88796f9207
RDX: 0000000001aa6ee0 RSI: 00007ffcf12607e0 RDI: 00007ffcf12617f0
RBP: 0000000000625500 R08: 0000000000000a11 R09: 0000000000000a11
program syz-executor4 is using a deprecated SCSI ioctl, please convert it to SG_IO
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000001aa6ee0
R13: 0000000000000007 R14: 0000000001a95250 R15: 0000000000000005

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:528
 rcu_segcblist_enqueue+0x24c/0x2d0 kernel/rcu/rcu_segcblist.c:150
 __call_rcu+0x227/0xef0 kernel/rcu/tree.c:3060
 call_rcu_sched+0x32/0x40 kernel/rcu/tree.c:3100
 free_pid+0x441/0x450 kernel/pid.c:156
 __change_pid kernel/pid.c:294 [inline]
 detach_pid+0x35a/0x370 kernel/pid.c:299
 __unhash_process kernel/exit.c:75 [inline]
 __exit_signal kernel/exit.c:156 [inline]
 release_task+0x10a0/0x2530 kernel/exit.c:200
 exit_notify kernel/exit.c:736 [inline]
 do_exit+0x2d91/0x38d0 kernel/exit.c:887
 do_group_exit+0x1a0/0x360 kernel/exit.c:970
 get_signal+0x1320/0x1f20 kernel/signal.c:2469
 do_signal+0xb8/0x1c80 arch/x86/kernel/signal.c:809
 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+0xe9/0x700 arch/x86/entry/common.c:265
 do_syscall_64+0x36d/0x430 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
Local variable description: ----tlb.i@ldt_arch_exit_mmap
Variable was created at:
 ldt_arch_exit_mmap+0x46/0x160 arch/x86/kernel/ldt.c:298
 arch_exit_mmap arch/x86/include/asm/mmu_context.h:244 [inline]
 exit_mmap+0x30f/0x950 mm/mmap.c:3009
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