gre0: entered promiscuous mode gretap0: entered promiscuous mode erspan0: entered promiscuous mode ================================================================== BUG: KCSAN: data-race in _prb_read_valid / data_alloc write to 0xffffffff86c6f1c0 of 8 bytes by task 16707 on cpu 1: data_alloc+0x2fc/0x380 kernel/printk/printk_ringbuffer.c:1129 prb_reserve+0x8e3/0xaf0 kernel/printk/printk_ringbuffer.c:1727 vprintk_store+0x54a/0x910 kernel/printk/printk.c:2354 vprintk_emit+0x1a4/0x600 kernel/printk/printk.c:2455 vprintk_default+0x26/0x30 kernel/printk/printk.c:2494 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2504 validate_nla lib/nlattr.c:414 [inline] __nla_validate_parse+0x127b/0x1d70 lib/nlattr.c:635 __nla_parse+0x40/0x60 lib/nlattr.c:732 __nlmsg_parse include/net/netlink.h:789 [inline] nlmsg_parse_deprecated include/net/netlink.h:830 [inline] rtnl_newlink+0xef/0x1400 net/core/rtnetlink.c:4064 rtnetlink_rcv_msg+0x64b/0x720 net/core/rtnetlink.c:7076 netlink_rcv_skb+0x11e/0x220 net/netlink/af_netlink.c:2556 rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:7103 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x5a7/0x680 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x5be/0x6f0 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] ____sys_sendmsg+0x532/0x580 net/socket.c:2684 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2738 __sys_sendmsg net/socket.c:2770 [inline] __do_sys_sendmsg net/socket.c:2775 [inline] __se_sys_sendmsg net/socket.c:2773 [inline] __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2773 x64_sys_call+0x194c/0x3020 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffffffff86c6f1c0 of 16 bytes by task 16694 on cpu 0: desc_read kernel/printk/printk_ringbuffer.c:496 [inline] desc_read_finalized_seq kernel/printk/printk_ringbuffer.c:1934 [inline] prb_read kernel/printk/printk_ringbuffer.c:1982 [inline] _prb_read_valid+0x183/0x930 kernel/printk/printk_ringbuffer.c:2173 prb_read_valid+0x3c/0x60 kernel/printk/printk_ringbuffer.c:2245 printk_get_next_message+0xea/0x550 kernel/printk/printk.c:3052 console_emit_next_record kernel/printk/printk.c:3137 [inline] console_flush_one_record kernel/printk/printk.c:3269 [inline] console_flush_all+0x2bc/0x6b0 kernel/printk/printk.c:3343 __console_flush_and_unlock kernel/printk/printk.c:3373 [inline] console_unlock+0xa1/0x280 kernel/printk/printk.c:3413 vprintk_emit+0x3e4/0x600 kernel/printk/printk.c:2479 vprintk_default+0x26/0x30 kernel/printk/printk.c:2494 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2504 __netdev_printk+0x310/0x370 net/core/dev.c:12966 netdev_info+0xa6/0xd0 net/core/dev.c:13013 __dev_set_promiscuity+0x1e5/0x3c0 net/core/dev.c:9614 __dev_change_flags+0x266/0x490 net/core/dev.c:9763 netif_change_flags+0x53/0xc0 net/core/dev.c:9817 do_setlink+0x8fc/0x2860 net/core/rtnetlink.c:3215 rtnl_group_changelink net/core/rtnetlink.c:3863 [inline] __rtnl_newlink net/core/rtnetlink.c:4031 [inline] rtnl_newlink+0xf51/0x1400 net/core/rtnetlink.c:4159 rtnetlink_rcv_msg+0x64b/0x720 net/core/rtnetlink.c:7076 netlink_rcv_skb+0x11e/0x220 net/netlink/af_netlink.c:2556 rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:7103 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x5a7/0x680 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x5be/0x6f0 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] ____sys_sendmsg+0x532/0x580 net/socket.c:2684 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2738 __sys_sendmsg net/socket.c:2770 [inline] __do_sys_sendmsg net/socket.c:2775 [inline] __se_sys_sendmsg net/socket.c:2773 [inline] __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2773 x64_sys_call+0x194c/0x3020 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 16694 Comm: syz.7.13402 Tainted: G W syzkaller #0 PREEMPT(lazy) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 ================================================================== ip_vti0: entered promiscuous mode ip6_vti0: entered promiscuous mode sit0: entered promiscuous mode ip6tnl0: entered promiscuous mode ip6gre0: entered promiscuous mode syz_tun: entered promiscuous mode ip6gretap0: entered promiscuous mode bridge0: entered promiscuous mode vcan0: entered promiscuous mode bond0: entered promiscuous mode bond_slave_0: entered promiscuous mode bond_slave_1: entered promiscuous mode team0: entered promiscuous mode team_slave_0: entered promiscuous mode team_slave_1: entered promiscuous mode dummy0: entered promiscuous mode nlmon0: entered promiscuous mode vxcan0: entered promiscuous mode vxcan1: entered promiscuous mode veth0: entered promiscuous mode veth1: entered promiscuous mode wg0: entered promiscuous mode wg1: entered promiscuous mode wg2: entered promiscuous mode veth0_to_bridge: entered promiscuous mode veth1_to_bridge: entered promiscuous mode veth0_to_bond: entered promiscuous mode veth1_to_bond: entered promiscuous mode veth0_to_team: entered promiscuous mode veth1_to_team: entered promiscuous mode veth0_to_batadv: entered promiscuous mode batadv_slave_0: entered promiscuous mode veth1_to_batadv: entered promiscuous mode batadv_slave_1: entered promiscuous mode xfrm0: entered promiscuous mode veth0_to_hsr: entered promiscuous mode veth1_to_hsr: entered promiscuous mode hsr0: entered promiscuous mode veth1_virt_wifi: entered promiscuous mode veth0_virt_wifi: entered promiscuous mode vlan0: entered promiscuous mode vlan1: entered promiscuous mode macvlan0: entered promiscuous mode macvlan1: entered promiscuous mode ipvlan0: entered promiscuous mode ipvlan1: entered promiscuous mode macvtap0: entered promiscuous mode macsec0: entered promiscuous mode geneve0: entered promiscuous mode geneve1: entered promiscuous mode netdevsim netdevsim7 netdevsim0: entered promiscuous mode netdevsim netdevsim7 netdevsim1: entered promiscuous mode netdevsim netdevsim7 netdevsim2: entered promiscuous mode netdevsim netdevsim7 netdevsim3: entered promiscuous mode ¥: entered promiscuous mode syz.7.13402 (16694) used greatest stack depth: 8760 bytes left