BUG: kernel NULL pointer dereference, address: 00000000000001a8 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 8000000120d18067 P4D 8000000120d18067 PUD 0 Oops: Oops: 0000 [#1] SMP PTI CPU: 0 UID: 0 PID: 6442 Comm: syz.1.17 Not tainted 6.16.0-rc3-syzkaller #0 PREEMPT(undef) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:htb_deactivate net/sched/sch_htb.c:613 [inline] RIP: 0010:htb_qlen_notify+0x13/0x60 net/sched/sch_htb.c:1489 Code: 00 cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 56 53 48 89 f3 49 89 fe e8 0d 11 c8 fe <8b> ab a8 01 00 00 31 ff 89 ee e8 3e 15 c8 fe 85 ed 74 23 e8 f5 10 RSP: 0018:ffffc90001e0b710 EFLAGS: 00010293 RAX: ffffffff8290ca33 RBX: 0000000000000000 RCX: ffff88810c3a9b80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888105f92000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000007 R10: 0000000000000000 R11: ffffffff8290ca20 R12: 00000000000afff2 R13: ffffffff83368468 R14: ffff888105f92000 R15: ffff888105f92000 FS: 00007f11fe95f6c0(0000) GS:ffff8882b2b07000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000001a8 CR3: 0000000117bb8000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: qdisc_tree_reduce_backlog+0x105/0x180 net/sched/sch_api.c:811 fq_change+0xb0d/0xc50 net/sched/sch_fq.c:1147 qdisc_create+0x46d/0x7c0 net/sched/sch_api.c:1324 __tc_modify_qdisc net/sched/sch_api.c:-1 [inline] tc_modify_qdisc+0xb42/0xf50 net/sched/sch_api.c:1813 rtnetlink_rcv_msg+0x586/0x610 net/core/rtnetlink.c:6953 netlink_rcv_skb+0x16a/0x240 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x3bd/0x480 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x494/0x590 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0xc6/0xf0 net/socket.c:727 ____sys_sendmsg+0x257/0x360 net/socket.c:2566 ___sys_sendmsg+0x2de/0x320 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inline] __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0x110/0x1a0 net/socket.c:2655 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x8f/0x250 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f11feeee929 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:00007f11fe95f038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f11ff115fa0 RCX: 00007f11feeee929 RDX: 0000000000044080 RSI: 0000200000000040 RDI: 0000000000000006 RBP: 00007f11fef70b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f11ff115fa0 R15: 00007ffd80593438 Modules linked in: CR2: 00000000000001a8 ---[ end trace 0000000000000000 ]--- RIP: 0010:htb_deactivate net/sched/sch_htb.c:613 [inline] RIP: 0010:htb_qlen_notify+0x13/0x60 net/sched/sch_htb.c:1489 Code: 00 cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 56 53 48 89 f3 49 89 fe e8 0d 11 c8 fe <8b> ab a8 01 00 00 31 ff 89 ee e8 3e 15 c8 fe 85 ed 74 23 e8 f5 10 RSP: 0018:ffffc90001e0b710 EFLAGS: 00010293 RAX: ffffffff8290ca33 RBX: 0000000000000000 RCX: ffff88810c3a9b80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888105f92000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000007 R10: 0000000000000000 R11: ffffffff8290ca20 R12: 00000000000afff2 R13: ffffffff83368468 R14: ffff888105f92000 R15: ffff888105f92000 FS: 00007f11fe95f6c0(0000) GS:ffff8882b2b07000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000001a8 CR3: 0000000117bb8000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 00 cc add %cl,%ah 2: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 7: 90 nop 8: 90 nop 9: 90 nop a: 90 nop b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: f3 0f 1e fa endbr64 1b: 55 push %rbp 1c: 41 56 push %r14 1e: 53 push %rbx 1f: 48 89 f3 mov %rsi,%rbx 22: 49 89 fe mov %rdi,%r14 25: e8 0d 11 c8 fe call 0xfec81137 * 2a: 8b ab a8 01 00 00 mov 0x1a8(%rbx),%ebp <-- trapping instruction 30: 31 ff xor %edi,%edi 32: 89 ee mov %ebp,%esi 34: e8 3e 15 c8 fe call 0xfec81577 39: 85 ed test %ebp,%ebp 3b: 74 23 je 0x60 3d: e8 .byte 0xe8 3e: f5 cmc 3f: 10 .byte 0x10