------------[ cut here ]------------ WARNING: CPU: 0 PID: 10956 at net/sched/sch_taprio.c:999 __refcount_sub_and_test include/linux/refcount.h:283 [inline] WARNING: CPU: 0 PID: 10956 at net/sched/sch_taprio.c:999 __refcount_dec_and_test include/linux/refcount.h:315 [inline] WARNING: CPU: 0 PID: 10956 at net/sched/sch_taprio.c:999 refcount_dec_and_test include/linux/refcount.h:333 [inline] WARNING: CPU: 0 PID: 10956 at net/sched/sch_taprio.c:999 taprio_offload_free net/sched/sch_taprio.c:1151 [inline] WARNING: CPU: 0 PID: 10956 at net/sched/sch_taprio.c:999 taprio_enable_offload net/sched/sch_taprio.c:1261 [inline] WARNING: CPU: 0 PID: 10956 at net/sched/sch_taprio.c:999 taprio_change+0x5005/0x5b60 net/sched/sch_taprio.c:1513 Modules linked in: CPU: 0 PID: 10956 Comm: syz-executor.1 Not tainted 5.12.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:taprio_get_start_time include/linux/refcount.h:283 [inline] RIP: 0010:taprio_change+0x5005/0x5b60 net/sched/sch_taprio.c:1550 Code: ff 48 89 df e8 fc ec c0 f9 e9 8a b7 ff ff e8 92 6c 7a f9 48 8b bc 24 b0 00 00 00 be 03 00 00 00 e8 70 c8 f1 fb e9 74 f3 ff ff <0f> 0b 48 c7 c7 a0 6e 35 8b e8 8d 08 07 00 48 83 7c 24 08 00 0f 84 RSP: 0018:ffffc90001c6ee00 EFLAGS: 00010246 RAX: 0000000000000002 RBX: 0000000000000000 RCX: 1ffff11003b1c886 RDX: ffff8880153c9c40 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90001c6f110 R08: ffffffff8804165c R09: fffffbfff1f992cc R10: fffffbfff1f992cc R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000000 R14: 167948c89b092c35 R15: ffff88801216d000 FS: 00007fcc57afc700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000015c8708 CR3: 0000000011b57000 CR4: 00000000001526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: qdisc_create+0x83a/0x1620 net/sched/sch_api.c:1247 tc_modify_qdisc+0x9ef/0x2060 net/sched/sch_api.c:1663 rtnetlink_rcv_msg+0xb34/0xe70 net/core/rtnetlink.c:5553 netlink_rcv_skb+0x1f0/0x460 net/netlink/af_netlink.c:2502 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline] netlink_unicast+0x7de/0x9b0 net/netlink/af_netlink.c:1338 netlink_sendmsg+0xaa6/0xe90 net/netlink/af_netlink.c:1927 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg net/socket.c:674 [inline] ____sys_sendmsg+0x5a2/0x900 net/socket.c:2350 ___sys_sendmsg net/socket.c:2404 [inline] __sys_sendmsg+0x319/0x400 net/socket.c:2433 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665f9 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fcc57afc188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000006 RBP: 00000000004bfbb9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007fff729e3c6f R14: 00007fcc57afc300 R15: 0000000000022000