syzbot


BUG: unable to handle kernel paging request in account_system_index_time

Status: fixed on 2018/08/07 13:43
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+8c02c0836b162b8737e5@syzkaller.appspotmail.com
Fix commit: 99ba2b5aba24 bpf: sockhash, disallow bpf_tcp_close and update in parallel
First crash: 2164d, last: 2164d

Sample crash report:
EXT4-fs (sda1): re-mounted. Opts: 
kasan: CONFIG_KASAN_INLINE enabled
BUG: unable to handle kernel paging request at ffff8801cada54f8
kasan: GPF could be caused by NULL-ptr deref or user memory access
PGD b4e2067 P4D b4e2067 PUD 1d9469063 PMD 1ba03a063 PTE 0
Thread overran stack, or stack corrupted
Oops: 0000 [#1] SMP KASAN
CPU: 0 PID: 20315 Comm: syz-executor5 Not tainted 4.18.0-rc3+ #58
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:188 [inline]
RIP: 0010:get_running_cputimer include/linux/sched/cputime.h:85 [inline]
RIP: 0010:account_group_system_time include/linux/sched/cputime.h:149 [inline]
RIP: 0010:account_system_index_time+0x10a/0x5c0 kernel/sched/cputime.c:168
Code: 00 48 8d 88 20 01 00 00 48 89 fe 48 c1 ee 03 0f b6 14 16 48 89 fe 83 e6 07 40 38 f2 7f 08 84 d2 0f 85 f9 03 00 00 4d 8d 67 80 <0f> b6 b0 38 01 00 00 48 ba 00 00 00 00 00 fc ff df 4c 89 e7 48 c1 
RSP: 0018:ffff8801dae07988 EFLAGS: 00010046
RAX: ffff8801cada53c0 RBX: ffff8801c53ca0c0 RCX: ffff8801cada54e0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8801cada54f8
RBP: ffff8801dae07a68 R08: ffff8801c53ca0c0 R09: fffffbfff11f424c
R10: fffffbfff11c1b45 R11: ffffffff88fa1263 R12: ffff8801dae079c0
R13: 00000000000f4240 R14: 1ffff1003b5c0f34 R15: ffff8801dae07a40
FS:  000000000231a940(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff8801cada54f8 CR3: 00000001b2bcd000 CR4: 00000000001406f0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 account_system_time+0x7f/0xb0 kernel/sched/cputime.c:199
 account_process_tick+0x76/0x240 kernel/sched/cputime.c:498
 update_process_times+0x21/0x70 kernel/time/timer.c:1634
 tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164
 tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0x3eb/0x10c0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline]
 smp_apic_timer_interrupt+0x165/0x730 arch/x86/kernel/apic/apic.c:1050
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
 </IRQ>
Modules linked in:
Dumping ftrace buffer:
   (ftrace buffer empty)
CR2: ffff8801cada54f8
---[ end trace 29e68111158e7e5b ]---
general protection fault: 0000 [#2] SMP KASAN
CPU: 1 PID: 20334 Comm: syz-executor4 Tainted: G      D           4.18.0-rc3+ #58
RIP: 0010:__read_once_size include/linux/compiler.h:188 [inline]
RIP: 0010:get_running_cputimer include/linux/sched/cputime.h:85 [inline]
RIP: 0010:account_group_system_time include/linux/sched/cputime.h:149 [inline]
RIP: 0010:account_system_index_time+0x10a/0x5c0 kernel/sched/cputime.c:168
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Code: 
RIP: 0010:find_stack lib/stackdepot.c:188 [inline]
RIP: 0010:depot_save_stack+0x120/0x470 lib/stackdepot.c:238
00 
Code: 0f 
48 
00 4e 
8d 
8b 
88 
24 
20 
f5 c0 
01 
3a 
00 
c3 
00 
8a 
48 
4d 
89 
85 
fe 
e4 
48 
0f 
c1 
84 
ee 
d4 
03 
00 
0f 
00 
b6 
00 
14 
44 
16 
8d 47 
48 89 
ff 
fe 
49 
83 
c1 
e6 
e0 
07 40 
03 
38 
eb 
f2 
0d 
7f 
4d 
08 
8b 
84 d2 
24 
0f 
24 
85 
4d 
f9 
85 
03 
e4 0f 
00 
84 
00 
bd 
4d 
00 
8d 67 
00 
80 
00 
<0f> 
<41> 
b6 
39 
b0 
5c 
38 
24 
01 
08 
00 
75 
00 
ec 
48 ba 
41 
00 
3b 
00 
7c 
00 
24 
00 
0c 
00 
75 
fc 
e5 
ff 
48 
df 
8b 
4c 
01 
89 e7 
49 
48 
39 
c1 
44 
RSP: 0018:ffff8801dae07988 EFLAGS: 00010046
24 
18 
RAX: ffff8801cada53c0 RBX: ffff8801c53ca0c0 RCX: ffff8801cada54e0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8801cada54f8
RSP: 0018:ffff88019ca0f858 EFLAGS: 00010286
RBP: ffff8801dae07a68 R08: ffff8801c53ca0c0 R09: fffffbfff11f424c
R10: fffffbfff11c1b45 R11: ffffffff88fa1263 R12: ffff8801dae079c0
RAX: 0000000095734edc RBX: 0000000096b0f28b RCX: ffff88019ca0f8b8
R13: 00000000000f4240 R14: 1ffff1003b5c0f34 R15: ffff8801dae07a40
RDX: 00000000f6a9df25 RSI: 00000000006000c0 RDI: 000000000000000b
FS:  000000000231a940(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
RBP: ffff88019ca0f890 R08: 0000000000000050 R09: 000000002cc8a8f1
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
R10: 000000005f6a6738 R11: ffff8801daf236b3 R12: fc0000000000ba48
CR2: ffff8801cada54f8 CR3: 00000001b2bcd000 CR4: 00000000001406f0
R13: ffff88019ca0f8a0 R14: 000000000000f28b R15: ffff8801ac364f37
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
FS:  00000000024f6940(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/07/20 16:14 bpf-next 8ae71e76cf1f 49f35839 .config console log report ci-upstream-bpf-next-kasan-gce
* Struck through repros no longer work on HEAD.