Oops: general protection fault, probably for non-canonical address 0xdffffc001fffe000: 0000 [#1] SMP KASAN PTI
KASAN: probably user-memory-access in range [0x00000000ffff0000-0x00000000ffff0007]
CPU: 1 UID: 0 PID: 24304 Comm: syz.3.8033 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:percpu_ref_get_many+0x8d/0x140
Code: 01 48 c7 c7 00 4b 98 8b be 4b 03 00 00 48 c7 c2 40 4b 98 8b e8 24 bf 71 ff 49 bc 00 00 00 00 00 fc ff df 4c 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 ff e8 e4 4d f7 ff 49 8b 07 a8 03 75 62
RSP: 0018:ffffc90004fc7a40 EFLAGS: 00010006
RAX: 000000001fffe000 RBX: ffffffff822bc619 RCX: f0002b981406bd00
RDX: 0000000000000000 RSI: ffffffff8be33660 RDI: ffffffff8be33620
RBP: 0000000000000078 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f47087 R12: dffffc0000000000
R13: ffff88813663b540 R14: 0000000000000001 R15: 00000000ffff0000
FS:  00007f33cfd5a6c0(0000) GS:ffff8881a3c1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000032000 CR3: 000000010f400000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 refill_obj_stock+0x254/0x850
 __memcg_slab_free_hook+0x127/0x3d0
 kmem_cache_free+0x223/0x400
 __dequeue_signal+0x487/0x5b0
 dequeue_signal+0x140/0x370
 get_signal+0x55f/0x1340
 arch_do_signal_or_restart+0x9a/0x750
 exit_to_user_mode_loop+0x75/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f33cef8ebe9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f33cfd5a038 EFLAGS: 00000246
RAX: 0000000000032600 RBX: 00007f33cf1c5fa0 RCX: 00007f33cef8ebe9
RDX: 0000000000032600 RSI: 0000200000000040 RDI: 0000000000000006
RBP: 00007f33cf011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f33cf1c6038 R14: 00007f33cf1c5fa0 R15: 00007ffea80d9b98
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:percpu_ref_get_many+0x8d/0x140
Code: 01 48 c7 c7 00 4b 98 8b be 4b 03 00 00 48 c7 c2 40 4b 98 8b e8 24 bf 71 ff 49 bc 00 00 00 00 00 fc ff df 4c 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 ff e8 e4 4d f7 ff 49 8b 07 a8 03 75 62
RSP: 0018:ffffc90004fc7a40 EFLAGS: 00010006
RAX: 000000001fffe000 RBX: ffffffff822bc619 RCX: f0002b981406bd00
RDX: 0000000000000000 RSI: ffffffff8be33660 RDI: ffffffff8be33620
RBP: 0000000000000078 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f47087 R12: dffffc0000000000
R13: ffff88813663b540 R14: 0000000000000001 R15: 00000000ffff0000
FS:  00007f33cfd5a6c0(0000) GS:ffff8881a3c1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000032000 CR3: 000000010f400000 CR4: 00000000000006f0
