Unable to handle kernel paging request at virtual address dfff800000000000
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
Mem abort info:
  ESR = 0x0000000096000006
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x06: level 2 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000006
  CM = 0, WnR = 0
[dfff800000000000] address between user and kernel address ranges
Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026
pstate: 42400005 (nZcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : dequeue_head net/sched/sch_fq_codel.c:120 [inline]
pc : fq_codel_drop net/sched/sch_fq_codel.c:168 [inline]
pc : fq_codel_enqueue+0x844/0x1004 net/sched/sch_fq_codel.c:230
lr : fq_codel_drop net/sched/sch_fq_codel.c:162 [inline]
lr : fq_codel_enqueue+0x7c0/0x1004 net/sched/sch_fq_codel.c:230
sp : ffff8000080175c0
x29: ffff8000080176f0 x28: 0000000000000000 x27: 0000000000000000
x26: ffff8000080178c0 x25: 0000000000000001 x24: ffff700001002ed0
x23: 0000000000000000 x22: 00000000000003ff x21: ffff0000fcbc0000
x20: dfff800000000000 x19: 0000000000000000 x18: 1fffe00033e6db7e
x17: 00000000ffff0000 x16: ffff8000082dd284 x15: 0000000000000000
x14: 0000000000000003 x13: 1ffff00002a78071 x12: 000000007f5c582d
x11: ff00800010195ebc x10: 0000000000000000 x9 : 1fffe0001f978000
x8 : 0000000000000000 x7 : ffff8000083c7974 x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000
x2 : ffff0000db155328 x1 : 0000000000000000 x0 : 0000000000000000
dump_backtrace(regs = 000000004bd996ad tsk = 0000000000000000)
Call trace:
 dequeue_head net/sched/sch_fq_codel.c:120 [inline]
 fq_codel_drop net/sched/sch_fq_codel.c:168 [inline]
 fq_codel_enqueue+0x844/0x1004 net/sched/sch_fq_codel.c:230
 cbs_child_enqueue net/sched/sch_cbs.c:95 [inline]
 cbs_enqueue_soft+0x150/0x234 net/sched/sch_cbs.c:128
 cbs_enqueue+0x58/0x6c net/sched/sch_cbs.c:136
 dev_qdisc_enqueue+0x5c/0x388 net/core/dev.c:3900
 __dev_xmit_skb net/core/dev.c:3989 [inline]
 __dev_queue_xmit+0xaf0/0x3154 net/core/dev.c:4337
 dev_queue_xmit include/linux/netdevice.h:3053 [inline]
 tipc_l2_send_msg+0x2a0/0x364 net/tipc/bearer.c:519
 tipc_bearer_xmit_skb+0x240/0x380 net/tipc/bearer.c:578
 tipc_disc_timeout+0x4e8/0x630 net/tipc/discover.c:340
 call_timer_fn+0x1b8/0x96c kernel/time/timer.c:1701
 expire_timers kernel/time/timer.c:1752 [inline]
 __run_timers+0x478/0x6d8 kernel/time/timer.c:2023
 run_timer_softirq+0x7c/0x114 kernel/time/timer.c:2036
 handle_softirqs+0x318/0xc90 kernel/softirq.c:596
 __do_softirq+0x14/0x20 kernel/softirq.c:630
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:80
 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:897
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:85
 invoke_softirq kernel/softirq.c:477 [inline]
 __irq_exit_rcu+0x23c/0x430 kernel/softirq.c:679
 irq_exit_rcu+0x14/0x84 kernel/softirq.c:691
 __el1_irq arch/arm64/kernel/entry-common.c:472 [inline]
 el1_interrupt+0x38/0x54 arch/arm64/kernel/entry-common.c:486
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:491
 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:581
 arch_local_irq_enable+0xc/0x18 arch/arm64/include/asm/irqflags.h:35
 default_idle_call+0x68/0xd8 kernel/sched/idle.c:109
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x368/0x600 kernel/sched/idle.c:323
 cpu_startup_entry+0x5c/0x74 kernel/sched/idle.c:422
 secondary_start_kernel+0x190/0x1b4 arch/arm64/kernel/smp.c:265
 __secondary_switched+0xb0/0xb4 arch/arm64/kernel/head.S:618
Code: aa1503e0 961d8066 f94002b7 d343fee8 (38746908) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	aa1503e0 	mov	x0, x21
   4:	961d8066 	bl	0xfffffffff876019c
   8:	f94002b7 	ldr	x23, [x21]
   c:	d343fee8 	lsr	x8, x23, #3
* 10:	38746908 	ldrb	w8, [x8, x20] <-- trapping instruction