netdevsim netdevsim4 netdevsim3 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 ================================================================== BUG: KCSAN: data-race in data_push_tail / vsnprintf write to 0xffffffff88e586b0 of 11 bytes by task 12028 on cpu 0: vsnprintf+0x2ce/0x890 lib/vsprintf.c:2826 vscnprintf+0x41/0x90 lib/vsprintf.c:2939 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2216 vprintk_store+0x599/0x860 kernel/printk/printk.c:2336 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2475 __nla_validate_parse+0x1738/0x1d00 lib/nlattr.c:647 __nla_parse+0x40/0x60 lib/nlattr.c:732 __nlmsg_parse include/net/netlink.h:787 [inline] nlmsg_parse_deprecated include/net/netlink.h:828 [inline] rtnl_dellink+0xed/0x550 net/core/rtnetlink.c:3529 rtnetlink_rcv_msg+0x5fb/0x6d0 net/core/rtnetlink.c:6944 netlink_rcv_skb+0x123/0x220 net/netlink/af_netlink.c:2551 rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:6971 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5a5/0x680 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x58b/0x6b0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x142/0x180 net/socket.c:727 ____sys_sendmsg+0x31e/0x4e0 net/socket.c:2566 ___sys_sendmsg+0x17b/0x1d0 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inline] __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2655 x64_sys_call+0x2999/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffffffff88e586b8 of 8 bytes by task 12030 on cpu 1: data_make_reusable kernel/printk/printk_ringbuffer.c:594 [inline] data_push_tail+0xfd/0x420 kernel/printk/printk_ringbuffer.c:679 data_alloc+0xbf/0x2b0 kernel/printk/printk_ringbuffer.c:1054 prb_reserve+0x808/0xaf0 kernel/printk/printk_ringbuffer.c:1669 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2326 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426 dev_vprintk_emit+0x242/0x2a0 drivers/base/core.c:4917 dev_printk_emit+0x84/0xb0 drivers/base/core.c:4928 __netdev_printk+0x35c/0x3e0 net/core/dev.c:12509 netdev_info+0x9b/0xd0 net/core/dev.c:12564 nsim_udp_tunnel_unset_port+0x1bd/0x1e0 drivers/net/netdevsim/udp_tunnels.c:64 udp_tunnel_nic_device_sync_one net/ipv4/udp_tunnel_nic.c:-1 [inline] udp_tunnel_nic_device_sync_by_port net/ipv4/udp_tunnel_nic.c:246 [inline] __udp_tunnel_nic_device_sync+0x567/0x9c0 net/ipv4/udp_tunnel_nic.c:289 udp_tunnel_nic_flush+0x21b/0x300 net/ipv4/udp_tunnel_nic.c:670 udp_tunnel_nic_unregister net/ipv4/udp_tunnel_nic.c:864 [inline] udp_tunnel_nic_netdevice_event+0x791/0xc90 net/ipv4/udp_tunnel_nic.c:904 notifier_call_chain kernel/notifier.c:85 [inline] raw_notifier_call_chain+0x6c/0x1b0 kernel/notifier.c:453 call_netdevice_notifiers_info+0xae/0x100 net/core/dev.c:2230 call_netdevice_notifiers_extack net/core/dev.c:2268 [inline] call_netdevice_notifiers net/core/dev.c:2282 [inline] unregister_netdevice_many_notify+0xd9d/0x1690 net/core/dev.c:12077 unregister_netdevice_many net/core/dev.c:12140 [inline] unregister_netdevice_queue+0x1f5/0x220 net/core/dev.c:11984 unregister_netdevice include/linux/netdevice.h:3379 [inline] nsim_destroy+0xf4/0x360 drivers/net/netdevsim/netdev.c:1069 __nsim_dev_port_del+0xcf/0x110 drivers/net/netdevsim/dev.c:1428 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1440 [inline] nsim_dev_reload_destroy+0x1a3/0x2c0 drivers/net/netdevsim/dev.c:1661 nsim_dev_reload_down+0x67/0x80 drivers/net/netdevsim/dev.c:968 devlink_reload+0xaa/0x580 net/devlink/dev.c:461 devlink_nl_reload_doit+0x503/0x8f0 net/devlink/dev.c:584 genl_family_rcv_msg_doit+0x140/0x1b0 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x422/0x460 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x123/0x220 net/netlink/af_netlink.c:2551 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5a5/0x680 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x58b/0x6b0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x142/0x180 net/socket.c:727 ____sys_sendmsg+0x31e/0x4e0 net/socket.c:2566 ___sys_sendmsg+0x17b/0x1d0 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inline] __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2655 x64_sys_call+0x2999/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x000000010000284f -> 0x7365747962203420 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 12030 Comm: syz.4.14352 Tainted: G W 6.16.0-rc5-syzkaller-00121-gbc9ff192a6c9 #0 PREEMPT(voluntary) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 ================================================================== netdevsim netdevsim4 netdevsim2 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim4 netdevsim1 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim4 netdevsim0 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim4 eth0: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim4 eth1: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim4 eth2: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim4 eth3: set [1, 0] type 2 family 0 port 6081 - 0