Re: BUG: unable to handle kernel paging request in cpuacct_account_field

[Thomas Gleixner]

On Fri, 21 Jun 2019, syzbot wrote:

Cc+: ....

> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:    abf02e29 Merge tag 'pm-5.2-rc6' of git://git.kernel.org/pu..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=164d94f6a00000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=e5c77f8090a3b96b
> dashboard link: https://syzkaller.appspot.com/bug?extid=a952f743523593b39174
> compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1372abc6a00000
> 
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+a952f743523593b39174@xxxxxxxxxxxxxxxxxxxxxxxxx
> 
> BUG: unable to handle page fault for address: ffffde202771d9b9
> #PF: supervisor read access in kernel mode
> #PF: error_code(0x0000) - not-present page
> PGD 0 P4D 0
> Thread overran stack, or stack corrupted
> Oops: 0000 [#1] PREEMPT SMP KASAN
> CPU: 1 PID: 8777 Comm: syz-executor.5 Not tainted 5.2.0-rc5+ #38
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google
> 01/01/2011
> RIP: 0010:cpuacct_account_field+0x12b/0x2f0 kernel/sched/cpuacct.c:366
> Code: c5 60 02 75 88 48 89 fa 48 c1 ea 03 42 80 3c 32 00 0f 85 81 01 00 00 48
> 03 1c c5 60 02 75 88 4a 8d 3c 3b 48 89 f8 48 c1 e8 03 <42> 80 3c 30 00 0f 85
> 89 01 00 00 4e 01 2c 3b 49 8d bc 24 28 01 00
> RSP: 0018:ffff8880ae909c78 EFLAGS: 00010802
> RAX: 1fffe2202771d9b9 RBX: ffff11013b8ecdb8 RCX: ffffffff83358d3e
> RDX: 1ffffffff10ea04d RSI: ffffffff83358d4c RDI: ffff11013b8ecdc8
> RBP: ffff8880ae909ca8 R08: ffff888090866500 R09: 0000000000000001
> R10: fffffbfff1141b45 R11: ffff888090866500 R12: ffff88808cfecc80
> R13: 0000000000966a20 R14: dffffc0000000000 R15: 0000000000000010
> FS:  0000555555ff5940(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: ffffde202771d9b9 CR3: 000000008533e000 CR4: 00000000001406e0
> Call Trace:
> <IRQ>
> cgroup_account_cputime_field include/linux/cgroup.h:789 [inline]
> task_group_account_field kernel/sched/cputime.c:109 [inline]
> account_system_index_time+0x11d/0x390 kernel/sched/cputime.c:172
> irqtime_account_process_tick.isra.0+0x386/0x490 kernel/sched/cputime.c:389
> account_process_tick+0x27f/0x350 kernel/sched/cputime.c:484
> update_process_times+0x25/0x80 kernel/time/timer.c:1637
> tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167
> tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1298
> __run_hrtimer kernel/time/hrtimer.c:1389 [inline]
> __hrtimer_run_queues+0x33b/0xdd0 kernel/time/hrtimer.c:1451
> hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509
> local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
> smp_apic_timer_interrupt+0x111/0x550 arch/x86/kernel/apic/apic.c:1066
> apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:806
> </IRQ>
> Modules linked in:
> CR2: ffffde202771d9b9
> ---[ end trace 4a0799d29c250606 ]---
> RIP: 0010:cpuacct_account_field+0x12b/0x2f0 kernel/sched/cpuacct.c:366
> Code: c5 60 02 75 88 48 89 fa 48 c1 ea 03 42 80 3c 32 00 0f 85 81 01 00 00 48
> 03 1c c5 60 02 75 88 4a 8d 3c 3b 48 89 f8 48 c1 e8 03 <42> 80 3c 30 00 0f 85
> 89 01 00 00 4e 01 2c 3b 49 8d bc 24 28 01 00
> RSP: 0018:ffff8880ae909c78 EFLAGS: 00010802
> RAX: 1fffe2202771d9b9 RBX: ffff11013b8ecdb8 RCX: ffffffff83358d3e
> RDX: 1ffffffff10ea04d RSI: ffffffff83358d4c RDI: ffff11013b8ecdc8
> RBP: ffff8880ae909ca8 R08: ffff888090866500 R09: 0000000000000001
> R10: fffffbfff1141b45 R11: ffff888090866500 R12: ffff88808cfecc80
> R13: 0000000000966a20 R14: dffffc0000000000 R15: 0000000000000010
> FS:  0000555555ff5940(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: ffffde202771d9b9 CR3: 000000008533e000 CR4: 00000000001406e0
> 
> 
> ---
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> 
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