netlink: 24 bytes leftover after parsing attributes in process `syz.0.17'.
------------[ cut here ]------------
memcpy: detected field-spanning write (size 32) of single field "&new->sel" at net/sched/cls_u32.c:853 (size 16)
WARNING: CPU: 0 PID: 4482 at net/sched/cls_u32.c:853 u32_init_knode net/sched/cls_u32.c:853 [inline]
WARNING: CPU: 0 PID: 4482 at net/sched/cls_u32.c:853 u32_change+0x1748/0x2018 net/sched/cls_u32.c:919
Modules linked in:
CPU: 0 PID: 4482 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : u32_init_knode net/sched/cls_u32.c:853 [inline]
pc : u32_change+0x1748/0x2018 net/sched/cls_u32.c:919
lr : u32_init_knode net/sched/cls_u32.c:853 [inline]
lr : u32_change+0x1748/0x2018 net/sched/cls_u32.c:919
sp : ffff800020f16c60
x29: ffff800020f16dc0 x28: ffff0000d5b76400 x27: 1fffe0001ab6ec8d
x26: ffff800020f16f40 x25: ffff0000d5b77c00 x24: dfff800000000000
x23: 0000000000000010 x22: ffff7000041e2d9c x21: dfff800000000000
x20: ffff800020f17460 x19: ffff800017d7f000 x18: 0000000000000000
x17: 20646c6569662065 x16: ffff8000082dd25c x15: 2029323320657a69
x14: 0000000000000001 x13: 1ffff000041e2cdc x12: 0000000000000000
x11: ff00800008195f68 x10: 0000000000000000 x9 : 6f3069b14f5cf100
x8 : 6f3069b14f5cf100 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff800020f166f8 x4 : ffff800015484e80 x3 : ffff80000831d368
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000000
Call trace:
 u32_init_knode net/sched/cls_u32.c:853 [inline]
 u32_change+0x1748/0x2018 net/sched/cls_u32.c:919
 tc_new_tfilter+0xdc8/0x1468 net/sched/cls_api.c:2194
 rtnetlink_rcv_msg+0x6d4/0xcc4 net/core/rtnetlink.c:6157
 netlink_rcv_skb+0x220/0x3ec net/netlink/af_netlink.c:2516
 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6184
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x5fc/0x80c net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x6f0/0x9d8 net/netlink/af_netlink.c:1877
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x588/0x90c net/socket.c:2519
 ___sys_sendmsg net/socket.c:2573 [inline]
 __sys_sendmmsg+0x320/0x7ec net/socket.c:2659
 __do_sys_sendmmsg net/socket.c:2688 [inline]
 __se_sys_sendmmsg net/socket.c:2685 [inline]
 __arm64_sys_sendmmsg+0xa4/0xc0 net/socket.c:2685
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
irq event stamp: 2902
hardirqs last  enabled at (2901): [<ffff8000083138a0>] __up_console_sem+0xb4/0xfc kernel/printk/printk.c:261
hardirqs last disabled at (2902): [<ffff800011b9d0cc>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (2896): [<ffff8000081ae3b4>] softirq_handle_end kernel/softirq.c:439 [inline]
softirqs last  enabled at (2896): [<ffff8000081ae3b4>] handle_softirqs+0xb1c/0xc90 kernel/softirq.c:624
softirqs last disabled at (2865): [<ffff800008020e6c>] __do_softirq+0x14/0x20 kernel/softirq.c:630
---[ end trace 0000000000000000 ]---
Zero length message leads to an empty skb