Unable to handle kernel paging request at virtual address dfff800000000007
KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]
Mem abort info:
  ESR = 0x0000000096000005
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x05: level 1 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[dfff800000000007] address between user and kernel address ranges
Internal error: Oops: 0000000096000005 [#1]  SMP
Modules linked in:
CPU: 1 UID: 0 PID: 4851 Comm: syz.0.561 Not tainted syzkaller #0 PREEMPT 
Hardware name: linux,dummy-virt (DT)
pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : rb_first include/linux/rbtree.h:54 [inline]
pc : simple_xattrs_free+0x48/0x184 fs/xattr.c:1564
lr : __kernfs_new_node+0x524/0x78c fs/kernfs/dir.c:684
sp : ffff80008e8e7920
x29: ffff80008e8e7920 x28: ffff00002cb31ea8 x27: ffff800086f10d18
x26: ffff00000e16d068 x25: ffff800086f10000 x24: 0000000000000038
x23: ffff800086f10000 x22: ffff0000131de1e0 x21: 0000000000000000
x20: 1fffe000059663d3 x19: ffff00002cb31e10 x18: 0000000000000000
x17: 0000000000000000 x16: ffff00006a050504 x15: ffff800080b292a0
x14: ffff800080b29048 x13: ffff800080045c90 x12: ffff700011d1cec5
x11: 1ffff00011d1cec4 x10: ffff700011d1cec4 x9 : dfff800000000000
x8 : ffff80008e8e7628 x7 : ffff80008e8e7750 x6 : ffff80008e8e76a0
x5 : ffff80008e8e7688 x4 : 0000000000000003 x3 : 1fffe0000300f721
x2 : 0000000000000000 x1 : 0000000000000007 x0 : dfff800000000000
Call trace:
 rb_first include/linux/rbtree.h:54 [inline] (P)
 simple_xattrs_free+0x48/0x184 fs/xattr.c:1564 (P)
 __kernfs_new_node+0x524/0x78c fs/kernfs/dir.c:684
 kernfs_new_node+0xe8/0x148 fs/kernfs/dir.c:716
 kernfs_create_dir_ns+0x34/0x118 fs/kernfs/dir.c:1086
 cgroup_create kernel/cgroup/cgroup.c:5859 [inline]
 cgroup_mkdir+0x2bc/0xf94 kernel/cgroup/cgroup.c:6007
 kernfs_iop_mkdir+0xd0/0x168 fs/kernfs/dir.c:1271
 vfs_mkdir+0x4fc/0x7c0 fs/namei.c:5130
 do_mkdirat+0x30c/0x3f8 fs/namei.c:5164
 __do_sys_mkdir fs/namei.c:5191 [inline]
 __se_sys_mkdir fs/namei.c:5189 [inline]
 __arm64_sys_mkdir+0xb8/0x108 fs/namei.c:5189
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49
 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132
 do_el0_svc_compat+0x40/0x68 arch/arm64/kernel/syscall.c:157
 el0_svc_compat+0x50/0x278 arch/arm64/kernel/entry-common.c:875
 el0t_32_sync_handler+0x88/0xac arch/arm64/kernel/entry-common.c:893
 el0t_32_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:601
Code: f90002bf d343ff01 d2d00000 f2fbffe0 (38e06820) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	f90002bf 	str	xzr, [x21]
   4:	d343ff01 	lsr	x1, x24, #3
   8:	d2d00000 	mov	x0, #0x800000000000        	// #140737488355328
   c:	f2fbffe0 	movk	x0, #0xdfff, lsl #48
* 10:	38e06820 	ldrsb	w0, [x1, x0] <-- trapping instruction