general protection fault, probably for non-canonical address 0xdffffc0000000004: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027] CPU: 0 PID: 5174 Comm: syz.0.236 Not tainted 6.1.145-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:qdisc_tree_reduce_backlog+0x21c/0x470 net/sched/sch_api.c:802 Code: 74 08 48 89 ef e8 d4 05 93 f9 4d 89 ef 85 db 74 0a e8 18 8a 41 f9 4c 89 f5 eb 7a 48 8b 6d 00 48 8d 45 20 48 89 c3 48 c1 eb 03 <42> 80 3c 33 00 48 89 04 24 74 0d 48 8b 3c 24 e8 a0 05 93 f9 48 8b RSP: 0018:ffffc900048b6ec8 EFLAGS: 00010202 RAX: 0000000000000020 RBX: 0000000000000004 RCX: 0000000000000002 RDX: ffff88807b698000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffff88807b698000 R09: 0000000000000002 R10: 00000000ffffffff R11: 0000000000000002 R12: 00000000000affe0 R13: ffff888077532000 R14: dffffc0000000000 R15: ffff888077532000 FS: 00007f0888cbc6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc444cd2eb8 CR3: 0000000020781000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: codel_change+0x970/0xdb0 net/sched/sch_codel.c:177 codel_init+0x1d4/0x3a0 net/sched/sch_codel.c:196 qdisc_create+0x7cb/0x1090 net/sched/sch_api.c:1310 tc_modify_qdisc+0xb0f/0x1be0 net/sched/sch_api.c:-1 rtnetlink_rcv_msg+0x79b/0xed0 net/core/rtnetlink.c:6153 netlink_rcv_skb+0x1de/0x420 net/netlink/af_netlink.c:2493 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline] netlink_unicast+0x74c/0x8c0 net/netlink/af_netlink.c:1337 netlink_sendmsg+0x89e/0xbc0 net/netlink/af_netlink.c:1859 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x59b/0x970 net/socket.c:2519 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573 __sys_sendmsg net/socket.c:2602 [inline] __do_sys_sendmsg net/socket.c:2611 [inline] __se_sys_sendmsg+0x19e/0x270 net/socket.c:2609 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: 0033:0x7f0887d8e929 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:00007f0888cbc038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f0887fb6080 RCX: 00007f0887d8e929 RDX: 0000000000004000 RSI: 0000200000000280 RDI: 0000000000000003 RBP: 00007f0887e10b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f0887fb6080 R15: 00007ffe8a2cc5d8 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:qdisc_tree_reduce_backlog+0x21c/0x470 net/sched/sch_api.c:802 Code: 74 08 48 89 ef e8 d4 05 93 f9 4d 89 ef 85 db 74 0a e8 18 8a 41 f9 4c 89 f5 eb 7a 48 8b 6d 00 48 8d 45 20 48 89 c3 48 c1 eb 03 <42> 80 3c 33 00 48 89 04 24 74 0d 48 8b 3c 24 e8 a0 05 93 f9 48 8b RSP: 0018:ffffc900048b6ec8 EFLAGS: 00010202 RAX: 0000000000000020 RBX: 0000000000000004 RCX: 0000000000000002 RDX: ffff88807b698000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffff88807b698000 R09: 0000000000000002 R10: 00000000ffffffff R11: 0000000000000002 R12: 00000000000affe0 R13: ffff888077532000 R14: dffffc0000000000 R15: ffff888077532000 FS: 00007f0888cbc6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc444cd2eb8 CR3: 0000000020781000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 74 08 je 0xa 2: 48 89 ef mov %rbp,%rdi 5: e8 d4 05 93 f9 call 0xf99305de a: 4d 89 ef mov %r13,%r15 d: 85 db test %ebx,%ebx f: 74 0a je 0x1b 11: e8 18 8a 41 f9 call 0xf9418a2e 16: 4c 89 f5 mov %r14,%rbp 19: eb 7a jmp 0x95 1b: 48 8b 6d 00 mov 0x0(%rbp),%rbp 1f: 48 8d 45 20 lea 0x20(%rbp),%rax 23: 48 89 c3 mov %rax,%rbx 26: 48 c1 eb 03 shr $0x3,%rbx * 2a: 42 80 3c 33 00 cmpb $0x0,(%rbx,%r14,1) <-- trapping instruction 2f: 48 89 04 24 mov %rax,(%rsp) 33: 74 0d je 0x42 35: 48 8b 3c 24 mov (%rsp),%rdi 39: e8 a0 05 93 f9 call 0xf99305de 3e: 48 rex.W 3f: 8b .byte 0x8b