syzbot

RBP: 00007fe742683d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe742866fac R14: 00007fe742866fa0 R15: 00007fe742866fa0
watchdog: BUG: soft lockup - CPU#1 stuck for 123s! [syz.2.17:385]
Modules linked in:
CPU: 1 PID: 385 Comm: syz.2.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:qdisc_lookup+0x261/0x4e0 net/sched/sch_api.c:310
Code: 00 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 f7 e8 d2 89 ec fd 4d 8b 36 4d 85 f6 0f 84 ba 00 00 00 49 83 c6 10 4c 89 f0 <48> c1 e8 03 42 80 3c 28 00 74 08 4c 89 f7 e8 ac 89 ec fd 4d 8b 36
RSP: 0018:ffffc90000c76da8 EFLAGS: 00000282
RAX: ffff8881266ed010 RBX: 00000000ffff0000 RCX: ffff88810ceccf00
RDX: 0000000000000000 RSI: 00000000ffff0000 RDI: 0000000000000000
RBP: ffffc90000c76dd8 R08: ffff88810ceccf00 R09: 0000000000000002
R10: 00000000ffffffff R11: 0000000000000000 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff8881266ed010 R15: ffff88810fe7e000
FS:  0000555564010500(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe7424c3780 CR3: 000000010fe16000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 qdisc_tree_reduce_backlog+0x111/0x340 net/sched/sch_api.c:783
 codel_change+0x8fc/0xbe0 net/sched/sch_codel.c:180
 codel_init+0x1a8/0x390 net/sched/sch_codel.c:199
 qdisc_create+0x848/0x1220 net/sched/sch_api.c:1255
 tc_modify_qdisc+0x8a1/0x1490 net/sched/sch_api.c:-1
 rtnetlink_rcv_msg+0xa31/0xcc0 net/core/rtnetlink.c:5613
 netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2503
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5631
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x89c/0xb50 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:652 [inline]
 __sock_sendmsg net/socket.c:664 [inline]
 ____sys_sendmsg+0x5b7/0x8f0 net/socket.c:2376
 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2430
 __sys_sendmmsg+0x2ab/0x4c0 net/socket.c:2516
 __do_sys_sendmmsg net/socket.c:2545 [inline]
 __se_sys_sendmmsg net/socket.c:2542 [inline]
 __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2542
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fe7425ede59
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:00007ffe0cb9c898 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fe742866fa0 RCX: 00007fe7425ede59
RDX: 040000000000009f RSI: 00002000000002c0 RDI: 0000000000000005
RBP: 00007fe742683d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe742866fac R14: 00007fe742866fa0 R15: 00007fe742866fa0
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline]
NMI backtrace for cpu 0 skipped: idling at default_idle+0x12/0x20 arch/x86/kernel/process.c:717