syzbot

general protection fault, probably for non-canonical address 0xdffffc0000000037: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000001b8-0x00000000000001bf]
CPU: 1 PID: 701 Comm: syz.4.84 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2025
RIP: 0010:htb_deactivate net/sched/sch_htb.c:610 [inline]
RIP: 0010:htb_qlen_notify+0x30/0xc0 net/sched/sch_htb.c:1495
Code: 41 56 41 55 41 54 53 49 89 f6 49 89 ff 49 bc 00 00 00 00 00 fc ff df e8 3e e8 6b fd 4d 8d ae b8 01 00 00 4c 89 eb 48 c1 eb 03 <42> 0f b6 04 23 84 c0 75 56 45 8b 65 00 31 ff 44 89 e6 e8 39 ec 6b
RSP: 0018:ffffc90000af6e30 EFLAGS: 00010202
RAX: ffffffff84042132 RBX: 0000000000000037 RCX: 0000000000080000
RDX: ffffc9000264e000 RSI: 0000000000000191 RDI: 0000000000000192
RBP: ffffc90000af6e58 R08: ffff88810e22d100 R09: 0000000000000002
R10: 0000000000000000 R11: ffffffff84042110 R12: dffffc0000000000
R13: 00000000000001b8 R14: 0000000000000000 R15: ffff888119c0a000
FS:  00007f0f66f546c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ec0fff8 CR3: 000000010a052000 CR4: 00000000003526a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 qdisc_tree_reduce_backlog+0x20a/0x360 net/sched/sch_api.c:808
 codel_change+0x8b8/0xbf0 net/sched/sch_codel.c:177
 codel_init+0x1ea/0x410 net/sched/sch_codel.c:196
 qdisc_create+0x7f3/0x1040 net/sched/sch_api.c:1311
 tc_modify_qdisc+0x8ea/0x1900 net/sched/sch_api.c:-1
 rtnetlink_rcv_msg+0x9f4/0xcf0 net/core/rtnetlink.c:6153
 netlink_rcv_skb+0x1f2/0x440 net/netlink/af_netlink.c:2503
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6171
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x8b1/0xa30 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x8aa/0xbc0 net/netlink/af_netlink.c:1860
 sock_sendmsg_nosec net/socket.c:716 [inline]
 __sock_sendmsg net/socket.c:728 [inline]
 ____sys_sendmsg+0x5a9/0x990 net/socket.c:2509
 ___sys_sendmsg+0x21c/0x290 net/socket.c:2563
 __sys_sendmsg net/socket.c:2592 [inline]
 __do_sys_sendmsg net/socket.c:2601 [inline]
 __se_sys_sendmsg net/socket.c:2599 [inline]
 __x64_sys_sendmsg+0x1f0/0x2c0 net/socket.c:2599
 x64_sys_call+0x171/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0f6618ebe9
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:00007f0f66f54038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f0f663c6090 RCX: 00007f0f6618ebe9
RDX: 000000000000c010 RSI: 0000200000000280 RDI: 0000000000000008
RBP: 00007f0f66211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0f663c6128 R14: 00007f0f663c6090 R15: 00007fff84b67588
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:htb_deactivate net/sched/sch_htb.c:610 [inline]
RIP: 0010:htb_qlen_notify+0x30/0xc0 net/sched/sch_htb.c:1495
Code: 41 56 41 55 41 54 53 49 89 f6 49 89 ff 49 bc 00 00 00 00 00 fc ff df e8 3e e8 6b fd 4d 8d ae b8 01 00 00 4c 89 eb 48 c1 eb 03 <42> 0f b6 04 23 84 c0 75 56 45 8b 65 00 31 ff 44 89 e6 e8 39 ec 6b
RSP: 0018:ffffc90000af6e30 EFLAGS: 00010202
RAX: ffffffff84042132 RBX: 0000000000000037 RCX: 0000000000080000
RDX: ffffc9000264e000 RSI: 0000000000000191 RDI: 0000000000000192
RBP: ffffc90000af6e58 R08: ffff88810e22d100 R09: 0000000000000002
R10: 0000000000000000 R11: ffffffff84042110 R12: dffffc0000000000
R13: 00000000000001b8 R14: 0000000000000000 R15: ffff888119c0a000
FS:  00007f0f66f546c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ec0fff8 CR3: 000000010a052000 CR4: 00000000003526a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	41 56                	push   %r14
   2:	41 55                	push   %r13
   4:	41 54                	push   %r12
   6:	53                   	push   %rbx
   7:	49 89 f6             	mov    %rsi,%r14
   a:	49 89 ff             	mov    %rdi,%r15
   d:	49 bc 00 00 00 00 00 	movabs $0xdffffc0000000000,%r12
  14:	fc ff df
  17:	e8 3e e8 6b fd       	call   0xfd6be85a
  1c:	4d 8d ae b8 01 00 00 	lea    0x1b8(%r14),%r13
  23:	4c 89 eb             	mov    %r13,%rbx
  26:	48 c1 eb 03          	shr    $0x3,%rbx
* 2a:	42 0f b6 04 23       	movzbl (%rbx,%r12,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	75 56                	jne    0x89
  33:	45 8b 65 00          	mov    0x0(%r13),%r12d
  37:	31 ff                	xor    %edi,%edi
  39:	44 89 e6             	mov    %r12d,%esi
  3c:	e8                   	.byte 0xe8
  3d:	39 ec                	cmp    %ebp,%esp
  3f:	6b                   	.byte 0x6b