BUG: KCSAN: data-race in _prb_read_valid / prb_reserve write to 0xffffffff868fd280 of 88 bytes by task 21523 on cpu 1: prb_reserve+0x695/0xaf0 kernel/printk/printk_ringbuffer.c:1651 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2299 vprintk_emit+0x10d/0x580 kernel/printk/printk.c:2399 vprintk_default+0x26/0x30 kernel/printk/printk.c:2438 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2448 fail_dump lib/fault-inject.c:66 [inline] should_fail_ex+0x24d/0x280 lib/fault-inject.c:174 should_failslab+0x8c/0xb0 mm/failslab.c:46 slab_pre_alloc_hook mm/slub.c:4908 [inline] slab_alloc_node mm/slub.c:5241 [inline] __kmalloc_cache_noprof+0x4c/0x4a0 mm/slub.c:5743 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] alloc_pipe_info+0xae/0x350 fs/pipe.c:800 splice_direct_to_actor+0x592/0x680 fs/splice.c:1049 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0xda/0x150 fs/splice.c:1230 do_sendfile+0x380/0x650 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64 fs/read_write.c:1417 [inline] __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1417 x64_sys_call+0x2bb4/0x3000 arch/x86/include/generated/asm/syscalls_64.h:41 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 0xffffffff868fd280 of 8 bytes by task 11977 on cpu 0: desc_read kernel/printk/printk_ringbuffer.c:483 [inline] desc_read_finalized_seq kernel/printk/printk_ringbuffer.c:1892 [inline] prb_read kernel/printk/printk_ringbuffer.c:1940 [inline] _prb_read_valid+0x1c4/0x920 kernel/printk/printk_ringbuffer.c:2131 desc_update_last_finalized kernel/printk/printk_ringbuffer.c:1531 [inline] prb_final_commit+0x136/0x1e0 kernel/printk/printk_ringbuffer.c:1800 vprintk_store+0x741/0x860 kernel/printk/printk.c:2325 vprintk_emit+0x10d/0x580 kernel/printk/printk.c:2399 vprintk_default+0x26/0x30 kernel/printk/printk.c:2438 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2448 __netdev_printk+0x321/0x3e0 net/core/dev.c:12724 netdev_info+0x9b/0xd0 net/core/dev.c:12771 __dev_set_promiscuity+0x233/0x450 net/core/dev.c:9449 netif_set_promiscuity+0x39/0x90 net/core/dev.c:9484 dev_set_promiscuity+0xc1/0x170 net/core/dev_api.c:287 hsr_del_port+0x13b/0x1a0 net/hsr/hsr_slave.c:243 hsr_del_ports+0x31/0xc0 net/hsr/hsr_device.c:468 hsr_dellink+0x5b/0xa0 net/hsr/hsr_netlink.c:136 default_device_exit_batch+0x47b/0x560 net/core/dev.c:12846 ops_exit_list net/core/net_namespace.c:205 [inline] ops_undo_list+0x2c0/0x410 net/core/net_namespace.c:252 cleanup_net+0x2f4/0x4f0 net/core/net_namespace.c:695 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3346 worker_thread+0x582/0x770 kernel/workqueue.c:3427 kthread+0x489/0x510 kernel/kthread.c:463 ret_from_fork+0x122/0x1b0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 value changed: 0x000000000000b25e -> 0x000000000000d25e Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 11977 Comm: kworker/u8:61 Tainted: G W syzkaller #0 PREEMPT(voluntary) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: netns cleanup_net ================================================================== hsr_slave_1: left promiscuous mode batman_adv: batadv0: Interface deactivated: batadv_slave_0 batman_adv: batadv0: Removing interface: batadv_slave_0 veth1_macvtap: left promiscuous mode veth0_macvtap: left promiscuous mode veth1_vlan: left promiscuous mode veth0_vlan: left promiscuous mode pimreg (unregistering): left allmulticast mode team0 (unregistering): Port device team_slave_1 removed team0 (unregistering): Port device team_slave_0 removed netdevsim netdevsim8 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim8 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim8 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim8 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0 bridge0: port 1(bridge_slave_0) entered blocking state bridge0: port 1(bridge_slave_0) entered forwarding state bridge0: port 2(bridge_slave_1) entered blocking state bridge0: port 2(bridge_slave_1) entered forwarding state