------------[ cut here ]------------
WARNING: CPU: 1 PID: 19738 at net/sched/sch_taprio.c:999 __refcount_sub_and_test include/linux/refcount.h:283 [inline]
WARNING: CPU: 1 PID: 19738 at net/sched/sch_taprio.c:999 __refcount_dec_and_test include/linux/refcount.h:315 [inline]
WARNING: CPU: 1 PID: 19738 at net/sched/sch_taprio.c:999 refcount_dec_and_test include/linux/refcount.h:333 [inline]
WARNING: CPU: 1 PID: 19738 at net/sched/sch_taprio.c:999 taprio_offload_free net/sched/sch_taprio.c:1151 [inline]
WARNING: CPU: 1 PID: 19738 at net/sched/sch_taprio.c:999 taprio_enable_offload net/sched/sch_taprio.c:1261 [inline]
WARNING: CPU: 1 PID: 19738 at net/sched/sch_taprio.c:999 taprio_change+0x4ce7/0x5830 net/sched/sch_taprio.c:1513
Modules linked in:
CPU: 1 PID: 19738 Comm: syz-executor.1 Not tainted 5.12.0-rc7-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+0x4ce7/0x5830 net/sched/sch_taprio.c:1550
Code: f4 b9 ff ff e8 ca bc bb f9 48 8b bc 24 a0 00 00 00 be 03 00 00 00 e8 88 54 17 fc 49 bc 00 00 00 00 00 fc ff df e9 1b eb ff ff <0f> 0b 48 c7 c7 a0 6e d5 8a e8 fb b4 06 00 48 83 7c 24 10 00 0f 84
RSP: 0018:ffffc900074df440 EFLAGS: 00010246
RAX: 0000000000000002 RBX: 0000000000000000 RCX: 1ffff11005c35696
RDX: ffff88801f680000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900074df610 R08: ffffffff87bd5624 R09: fffffbfff1f270cc
R10: fffffbfff1f270cc R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff87bda400 R15: 1676b6f34ac654b9
FS:  00007fd0c47c6700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ee22000 CR3: 00000000130c6000 CR4: 00000000001526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 qdisc_create+0x7d3/0x1510 net/sched/sch_api.c:1247
 tc_modify_qdisc+0x97f/0x1e40 net/sched/sch_api.c:1663
 rtnetlink_rcv_msg+0x895/0xd50 net/core/rtnetlink.c:5553
 netlink_rcv_skb+0x190/0x3a0 net/netlink/af_netlink.c:2502
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x786/0x940 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x9ae/0xd50 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 ____sys_sendmsg+0x519/0x800 net/socket.c:2350
 ___sys_sendmsg net/socket.c:2404 [inline]
 __sys_sendmsg+0x2bf/0x370 net/socket.c:2433
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x466459
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:00007fd0c47c6188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000005
RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007fff6be9331f R14: 00007fd0c47c6300 R15: 0000000000022000