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
CPU: 1 PID: 6732 Comm: syz-executor.3 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:vgem_fence_attach_ioctl+0x27d/0x640 drivers/gpu/drm/vgem/vgem_fence.c:184
Code: 03 80 3c 02 00 0f 85 9b 03 00 00 4c 8b b5 10 01 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d be e0 00 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 7f 03 00 00 4c 89 ea 4d 8b b6 e0 00 00 00 48 b8
RSP: 0018:ffff88804d807af0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff88804d807c58 RCX: 1ffff11009b00f4b
RDX: 000000000000001c RSI: ffffffff8153c5cf RDI: 00000000000000e0
RBP: ffff8880a50b4080 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88809ddc7c00
R13: ffff88804d807c5c R14: 0000000000000000 R15: ffff88809ddc7c98
FS:  00007fcf11ee8700(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd79e07cb8 CR3: 0000000090e4e000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 drm_ioctl_kernel+0x208/0x2a0 drivers/gpu/drm/drm_ioctl.c:758
 drm_ioctl+0x5a0/0x9e0 drivers/gpu/drm/drm_ioctl.c:861
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688
 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fcf135730e9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcf11ee8168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fcf13685f60 RCX: 00007fcf135730e9
RDX: 0000000020000040 RSI: 00000000c0106441 RDI: 0000000000000003
RBP: 00007fcf135cd08d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc6885490f R14: 00007fcf11ee8300 R15: 0000000000022000
Modules linked in:
---[ end trace b3ceebec96a69b79 ]---
RIP: 0010:vgem_fence_attach_ioctl+0x27d/0x640 drivers/gpu/drm/vgem/vgem_fence.c:184
Code: 03 80 3c 02 00 0f 85 9b 03 00 00 4c 8b b5 10 01 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d be e0 00 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 7f 03 00 00 4c 89 ea 4d 8b b6 e0 00 00 00 48 b8
RSP: 0018:ffff88804d807af0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff88804d807c58 RCX: 1ffff11009b00f4b
attempt to access beyond end of device
loop0: rw=2049, want=230, limit=87
RDX: 000000000000001c RSI: ffffffff8153c5cf RDI: 00000000000000e0
attempt to access beyond end of device
RBP: ffff8880a50b4080 R08: 0000000000000000 R09: 0000000000000000
loop0: rw=524288, want=190, limit=87
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88809ddc7c00
attempt to access beyond end of device
loop0: rw=0, want=102, limit=87
R13: ffff88804d807c5c R14: 0000000000000000 R15: ffff88809ddc7c98
attempt to access beyond end of device
FS:  00007fcf11ee8700(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
loop0: rw=0, want=102, limit=87
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe1c385c20 CR3: 0000000090e4e000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	03 80 3c 02 00 0f    	add    0xf00023c(%rax),%eax
   6:	85 9b 03 00 00 4c    	test   %ebx,0x4c000003(%rbx)
   c:	8b b5 10 01 00 00    	mov    0x110(%rbp),%esi
  12:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  19:	fc ff df
  1c:	49 8d be e0 00 00 00 	lea    0xe0(%r14),%rdi
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 7f 03 00 00    	jne    0x3b3
  34:	4c 89 ea             	mov    %r13,%rdx
  37:	4d 8b b6 e0 00 00 00 	mov    0xe0(%r14),%r14
  3e:	48                   	rex.W
  3f:	b8                   	.byte 0xb8