RAX: ffffffffffffffda RBX: 00007ff089692c90 RCX: 0000000000458d99
RDX: 0000000020000140 RSI: 0000000000005423 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff0896936d4
R13: 00000000004c31f5 R14: 00000000004d6588 R15: 0000000000000004
BUG: unable to handle kernel paging request at fffffffffffffff4
PGD 7a6d067 P4D 7a6d067 PUD 7a6f067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 6866 Comm: syz-executor.1 Not tainted 4.17.0-rc1+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:slhc_free+0x24/0x80 drivers/net/slip/slhc.c:159
RSP: 0018:ffff88008d8579b8 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: fffffffffffffff4 RCX: 1ffff1001152d545
RDX: 1ffffffffffffffe RSI: ffff88008a96aa08 RDI: fffffffffffffff4
RBP: ffff88008d8579c0 R08: ffff88008a96aa28 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff10011b0af43
R13: ffff88008a56d780 R14: ffff88008a56ccc0 R15: fffffffffffffff4
FS:  00007ff089693700(0000) GS:ffff8800aec00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffff4 CR3: 000000008a80d000 CR4: 00000000001406f0
Call Trace:
 sl_alloc_bufs drivers/net/slip/slip.c:197 [inline]
 slip_open+0xcea/0x1092 drivers/net/slip/slip.c:822
 tty_ldisc_open.isra.1+0x64/0xa0 drivers/tty/tty_ldisc.c:466
 tty_set_ldisc+0x252/0x5b0 drivers/tty/tty_ldisc.c:591
 tiocsetd drivers/tty/tty_io.c:2336 [inline]
 tty_ioctl+0x31e/0x12a0 drivers/tty/tty_io.c:2580
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x199/0x1000 fs/ioctl.c:684
 ksys_ioctl+0x62/0x90 fs/ioctl.c:701
 __do_sys_ioctl fs/ioctl.c:708 [inline]
 __se_sys_ioctl fs/ioctl.c:706 [inline]
 __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:706
 do_syscall_64+0xd6/0x4e0 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458d99
RSP: 002b:00007ff089692c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ff089692c90 RCX: 0000000000458d99
RDX: 0000000020000140 RSI: 0000000000005423 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff0896936d4
R13: 00000000004c31f5 R14: 00000000004d6588 R15: 0000000000000004
Code: 1f 84 00 00 00 00 00 48 85 ff 74 60 48 b8 00 00 00 00 00 fc ff df 48 89 fa 55 48 c1 ea 03 48 89 e5 53 48 89 fb 80 3c 02 00 75 42 <48> 8b 3b 48 85 ff 74 05 e8 9f 67 9c fd 48 8d 7b 08 48 b8 00 00 
RIP: slhc_free+0x24/0x80 drivers/net/slip/slhc.c:159 RSP: ffff88008d8579b8
CR2: fffffffffffffff4
---[ end trace 6106a119c258341d ]---