BUG: unable to handle page fault for address: fffffffffffffbc8
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD cf35067 P4D cf35067 PUD cf37067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 11790 Comm: syz.0.1728 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:strlen+0x39/0x70 lib/string.c:425
Code: ff ff ff 49 be 00 00 00 00 00 fc ff df 48 89 fb 49 89 c7 48 89 d8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 11 48 ff c3 49 8d 47 01 <42> 80 7c 3f 01 00 75 de eb 19 89 d9 80 e1 07 38 c1 7c e6 49 89 fc
RSP: 0018:ffffc9000c3e6bd8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: fffffffffffffbc9 RCX: 0000000000080000
RDX: ffffc9000c9d9000 RSI: 0000000000000bef RDI: fffffffffffffbc8
RBP: ffffc9000c3e6d08 R08: ffffffff8e8c7caf R09: 1ffffffff1d18f95
R10: dffffc0000000000 R11: fffffbfff1d18f96 R12: dffffc0000000000
R13: ffff888018666680 R14: dffffc0000000000 R15: ffffffffffffffff
FS:  00007f7f3a08f6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffbc8 CR3: 000000004c833000 CR4: 00000000003506e0
DR0: 0000000000000008 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __fortify_strlen include/linux/fortify-string.h:228 [inline]
 trace_event_get_offsets_drv_net_setup_tc net/mac80211/trace.h:2499 [inline]
 do_trace_event_raw_event_drv_net_setup_tc net/mac80211/trace.h:2490 [inline]
 trace_event_raw_event_drv_net_setup_tc+0x109/0x4d0 net/mac80211/trace.h:2490
 trace_drv_net_setup_tc net/mac80211/trace.h:2490 [inline]
 drv_net_setup_tc net/mac80211/driver-ops.h:1538 [inline]
 ieee80211_netdev_setup_tc+0x2c2/0x320 net/mac80211/iface.c:873
 tcf_block_offload_cmd+0x235/0x3a0 net/sched/cls_api.c:809
 tcf_block_offload_bind net/sched/cls_api.c:846 [inline]
 tcf_block_get_ext+0xdf2/0x13d0 net/sched/cls_api.c:1458
 tcf_block_get+0x68/0xa0 net/sched/cls_api.c:1493
 multiq_init+0x72/0x2b0 net/sched/sch_multiq.c:246
 qdisc_create+0x90f/0x1060 net/sched/sch_api.c:1317
 tc_modify_qdisc+0xb47/0x1de0 net/sched/sch_api.c:-1
 rtnetlink_rcv_msg+0x843/0xf90 net/core/rtnetlink.c:6484
 netlink_rcv_skb+0x235/0x4c0 net/netlink/af_netlink.c:2550
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x7b1/0x930 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1899
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x61b/0x980 net/socket.c:2595
 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2649
 __sys_sendmsg net/socket.c:2678 [inline]
 __do_sys_sendmsg net/socket.c:2687 [inline]
 __se_sys_sendmsg+0x1d0/0x2c0 net/socket.c:2685
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7f3919e019
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7f3a08f028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f7f39425fa0 RCX: 00007f7f3919e019
RDX: 0000000000000000 RSI: 00002000000012c0 RDI: 0000000000000003
RBP: 00007f7f3923500c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7f39426038 R14: 00007f7f39425fa0 R15: 00007ffd7901f918
 </TASK>
Modules linked in:
CR2: fffffffffffffbc8
---[ end trace 0000000000000000 ]---
RIP: 0010:strlen+0x39/0x70 lib/string.c:425
Code: ff ff ff 49 be 00 00 00 00 00 fc ff df 48 89 fb 49 89 c7 48 89 d8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 11 48 ff c3 49 8d 47 01 <42> 80 7c 3f 01 00 75 de eb 19 89 d9 80 e1 07 38 c1 7c e6 49 89 fc
RSP: 0018:ffffc9000c3e6bd8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: fffffffffffffbc9 RCX: 0000000000080000
RDX: ffffc9000c9d9000 RSI: 0000000000000bef RDI: fffffffffffffbc8
RBP: ffffc9000c3e6d08 R08: ffffffff8e8c7caf R09: 1ffffffff1d18f95
R10: dffffc0000000000 R11: fffffbfff1d18f96 R12: dffffc0000000000
R13: ffff888018666680 R14: dffffc0000000000 R15: ffffffffffffffff
FS:  00007f7f3a08f6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffbc8 CR3: 000000004c833000 CR4: 00000000003506e0
DR0: 0000000000000008 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	ff 49 be             	decl   -0x42(%rcx)
   3:	00 00                	add    %al,(%rax)
   5:	00 00                	add    %al,(%rax)
   7:	00 fc                	add    %bh,%ah
   9:	ff                   	lcall  (bad)
   a:	df 48 89             	fisttps -0x77(%rax)
   d:	fb                   	sti
   e:	49 89 c7             	mov    %rax,%r15
  11:	48 89 d8             	mov    %rbx,%rax
  14:	48 c1 e8 03          	shr    $0x3,%rax
  18:	42 0f b6 04 30       	movzbl (%rax,%r14,1),%eax
  1d:	84 c0                	test   %al,%al
  1f:	75 11                	jne    0x32
  21:	48 ff c3             	inc    %rbx
  24:	49 8d 47 01          	lea    0x1(%r15),%rax
* 28:	42 80 7c 3f 01 00    	cmpb   $0x0,0x1(%rdi,%r15,1) <-- trapping instruction
  2e:	75 de                	jne    0xe
  30:	eb 19                	jmp    0x4b
  32:	89 d9                	mov    %ebx,%ecx
  34:	80 e1 07             	and    $0x7,%cl
  37:	38 c1                	cmp    %al,%cl
  39:	7c e6                	jl     0x21
  3b:	49 89 fc             	mov    %rdi,%r12