netdevsim netdevsim3 eth1: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim3 eth2: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim3 eth3: set [1, 0] type 2 family 0 port 6081 - 0 ================================================================== BUG: KCSAN: data-race in data_push_tail / string write to 0xffffffff88e5ea72 of 1 bytes by task 8114 on cpu 1: string_nocheck lib/vsprintf.c:643 [inline] string+0x17d/0x210 lib/vsprintf.c:721 vsnprintf+0x539/0x8a0 lib/vsprintf.c:2852 vscnprintf+0x42/0x90 lib/vsprintf.c:2917 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2216 vprintk_store+0x583/0x860 kernel/printk/printk.c:2336 vprintk_emit+0x1a0/0x6c0 kernel/printk/printk.c:2426 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x7f/0xb0 kernel/printk/printk.c:2475 set_capacity_and_notify+0x155/0x200 block/genhd.c:93 loop_set_size+0x2e/0x70 drivers/block/loop.c:210 loop_configure+0x89c/0xa30 drivers/block/loop.c:1120 lo_ioctl+0x5fa/0x1570 drivers/block/loop.c:-1 blkdev_ioctl+0x35b/0x450 block/ioctl.c:698 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xc9/0x140 fs/ioctl.c:892 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:892 x64_sys_call+0x168d/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:17 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffffffff88e5ea70 of 8 bytes by task 8084 on cpu 0: data_make_reusable kernel/printk/printk_ringbuffer.c:594 [inline] data_push_tail+0x107/0x440 kernel/printk/printk_ringbuffer.c:679 data_alloc+0xbd/0x2c0 kernel/printk/printk_ringbuffer.c:1054 prb_reserve+0x86a/0xb80 kernel/printk/printk_ringbuffer.c:1669 vprintk_store+0x552/0x860 kernel/printk/printk.c:2326 vprintk_emit+0x1a0/0x6c0 kernel/printk/printk.c:2426 dev_vprintk_emit+0x24a/0x2a0 drivers/base/core.c:4891 dev_printk_emit+0x84/0xb0 drivers/base/core.c:4902 __netdev_printk+0x352/0x3e0 net/core/dev.c:12392 netdev_info+0x9e/0xd0 net/core/dev.c:12447 nsim_udp_tunnel_set_port+0x175/0x190 drivers/net/netdevsim/udp_tunnels.c:34 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+0x594/0xa00 net/ipv4/udp_tunnel_nic.c:289 udp_tunnel_nic_device_sync net/ipv4/udp_tunnel_nic.c:312 [inline] __udp_tunnel_nic_add_port+0x68a/0x700 net/ipv4/udp_tunnel_nic.c:531 udp_tunnel_nic_add_port include/net/udp_tunnel.h:350 [inline] udp_tunnel_push_rx_port+0xee/0x120 net/ipv4/udp_tunnel_core.c:96 geneve_offload_rx_ports drivers/net/geneve.c:1185 [inline] geneve_netdevice_event+0x169/0x1c0 drivers/net/geneve.c:1929 notifier_call_chain kernel/notifier.c:85 [inline] raw_notifier_call_chain+0x6f/0x1d0 kernel/notifier.c:453 call_netdevice_notifiers_info+0xae/0x100 net/core/dev.c:2180 call_netdevice_notifiers_extack net/core/dev.c:2218 [inline] call_netdevice_notifiers+0x4e/0x70 net/core/dev.c:2232 udp_tunnel_get_rx_info include/net/udp_tunnel.h:138 [inline] udp_tunnel_nic_register net/ipv4/udp_tunnel_nic.c:825 [inline] udp_tunnel_nic_netdevice_event+0xa4a/0xc80 net/ipv4/udp_tunnel_nic.c:893 notifier_call_chain kernel/notifier.c:85 [inline] raw_notifier_call_chain+0x6f/0x1d0 kernel/notifier.c:453 call_netdevice_notifiers_info+0xae/0x100 net/core/dev.c:2180 call_netdevice_notifiers_extack net/core/dev.c:2218 [inline] call_netdevice_notifiers net/core/dev.c:2232 [inline] register_netdevice+0xd0b/0xed0 net/core/dev.c:11048 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:959 [inline] nsim_create+0x598/0x700 drivers/net/netdevsim/netdev.c:1019 __nsim_dev_port_add+0x4aa/0x670 drivers/net/netdevsim/dev.c:1393 nsim_dev_port_add_all drivers/net/netdevsim/dev.c:1449 [inline] nsim_dev_reload_create drivers/net/netdevsim/dev.c:1501 [inline] nsim_dev_reload_up+0x439/0x510 drivers/net/netdevsim/dev.c:988 devlink_reload+0x326/0x5b0 net/devlink/dev.c:474 devlink_nl_reload_doit+0x4da/0x930 net/devlink/dev.c:584 genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x69b/0x6f0 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x12f/0x230 net/netlink/af_netlink.c:2534 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x605/0x6c0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x609/0x720 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x140/0x180 net/socket.c:727 ____sys_sendmsg+0x350/0x4e0 net/socket.c:2566 ___sys_sendmsg net/socket.c:2620 [inline] __sys_sendmsg+0x1a0/0x240 net/socket.c:2652 __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2655 x64_sys_call+0x26f3/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x00000000ffffe827 -> 0x64203a31706f6f6c Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 8084 Comm: syz.3.1665 Not tainted 6.14.0-syzkaller-12886-ga1b5bd45d4ee #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 ================================================================== syz.3.1665 (8084) used greatest stack depth: 8176 bytes left