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: 0 PID: 4851 Comm: syz-executor.0 Not tainted 4.14.228-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff888037fc6380 task.stack: ffff888041540000
RIP: 0010:vgem_fence_attach_ioctl+0x2f8/0x6e0 drivers/gpu/drm/vgem/vgem_fence.c:184
RSP: 0018:ffff888041547bb0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8880a56b05c0 RCX: ffffc90005bcd000
RDX: 000000000000001c RSI: ffffffff81487ffc RDI: 00000000000000e0
RBP: ffff88809e279840 R08: ffffffff8c078188 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888099891e00
R13: 1ffff110082a8f78 R14: ffff8880a56b05c4 R15: 0000000000000000
FS:  00007ff9e4ed9700(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055883094b160 CR3: 00000000ba5c2000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 drm_ioctl_kernel+0x14c/0x200 drivers/gpu/drm/drm_ioctl.c:736
 drm_ioctl+0x419/0x870 drivers/gpu/drm/drm_ioctl.c:836
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x466459
RSP: 002b:00007ff9e4ed9188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 0000000020000140 RSI: 00000000c10c5541 RDI: 0000000000000004
RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffd752a486f R14: 00007ff9e4ed9300 R15: 0000000000022000
Code: ea 03 80 3c 02 00 0f 85 a2 03 00 00 4c 8b bd 18 01 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d bf e0 00 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 86 03 00 00 4c 89 f2 4d 8b bf e0 00 00 00 48 
RIP: vgem_fence_attach_ioctl+0x2f8/0x6e0 drivers/gpu/drm/vgem/vgem_fence.c:184 RSP: ffff888041547bb0
---[ end trace cd07d1e45e0064d8 ]---