general protection fault in update_vsyscall

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: c10b57a5 Linux 4.14.176
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13d078f7e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=457897b554d08537
dashboard link: https://syzkaller.appspot.com/bug?extid=3263c9ed47d96a971d44
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+3263c9...@syzkaller.appspotmail.com

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 3590 Comm: syz-executor.5 Not tainted 4.14.176-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880860a6280 task.stack: ffff888091d08000
RIP: 0010:update_vsyscall+0xa1/0x340 arch/x86/entry/vsyscall/vsyscall_gtod.c:43
RSP: 0018:ffff8880aeb07ca0 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: ffffffff87d15fe0 RCX: 0000000000000017
RDX: 1ffffffff14b152a RSI: 0000000000000000 RDI: ffffffff8a58a950
RBP: ffffffff8a58a940 R08: 0000000000007fd2 R09: ffffffff8a09c710
R10: ffff8880860a6bf0 R11: ffff8880860a6280 R12: 0000000000000000
R13: 0000000044f81099 R14: 00000000388c5ac4 R15: 00000000002c5528
FS: 00007f58a2667700(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30b23000 CR3: 000000009f862000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
timekeeping_update+0x223/0x390 kernel/time/timekeeping.c:656
update_wall_time+0x5a1/0xa30 kernel/time/timekeeping.c:2117
tick_do_update_jiffies64.part.0+0x172/0x270 kernel/time/tick-sched.c:100
tick_do_update_jiffies64 kernel/time/tick-sched.c:66 [inline]
tick_sched_do_timer kernel/time/tick-sched.c:139 [inline]
tick_sched_do_timer+0xab/0xe0 kernel/time/tick-sched.c:120
tick_sched_timer+0x25/0x120 kernel/time/tick-sched.c:1216
__run_hrtimer kernel/time/hrtimer.c:1223 [inline]
__hrtimer_run_queues+0x25c/0xbb0 kernel/time/hrtimer.c:1287
hrtimer_interrupt+0x1e6/0x5e0 kernel/time/hrtimer.c:1321
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline]
smp_apic_timer_interrupt+0x117/0x5e0 arch/x86/kernel/apic/apic.c:1100
apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792
</IRQ>
RIP: 0010:conv_uni_to_pc+0x15e/0x200 drivers/tty/vt/consolemap.c:835
RSP: 0018:ffff888091d0f9a8 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff10
RAX: 0000000000000006 RBX: ffff888219277016 RCX: ffffc9000747d000
RDX: 0000000000000000 RSI: ffffffff833dfebb RDI: 0000000000000010
RBP: ffff888219277000 R08: 0000000000000001 R09: 0000000000000000
R10: ffff8880860a6bc8 R11: ffff8880860a6280 R12: ffff8880a5b84690
R13: 000000000000008b R14: ffff8880aa4c0980 R15: ffff8880a082b7c4
do_con_write.part.0+0x4b2/0x1a20 drivers/tty/vt/vt.c:2363
do_con_write drivers/tty/vt/vt.c:2218 [inline]
con_write+0x33/0xc0 drivers/tty/vt/vt.c:2798
n_tty_write+0x8dd/0xe30 drivers/tty/n_tty.c:2356
do_tty_write drivers/tty/tty_io.c:959 [inline]
tty_write+0x3f0/0x700 drivers/tty/tty_io.c:1043
__vfs_write+0xe4/0x630 fs/read_write.c:480
vfs_write+0x192/0x4e0 fs/read_write.c:544
SYSC_write fs/read_write.c:590 [inline]
SyS_write+0xf2/0x210 fs/read_write.c:582
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45c869
RSP: 002b:00007f58a2666c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f58a26676d4 RCX: 000000000045c869
RDX: 0000000000001006 RSI: 0000000020001440 RDI: 000000000000000e
RBP: 000000000076c040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000cd4 R14: 00000000004cf001 R15: 000000000076c04c
Code: 89 05 18 5e 91 07 48 8d 7d 10 89 15 be 8e 6b 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 4d 02 00 00 <00> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
RIP: update_vsyscall+0xa1/0x340 arch/x86/entry/vsyscall/vsyscall_gtod.c:43 RSP: ffff8880aeb07ca0
---[ end trace 5905928ca4bd0141 ]---


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.