bridge_slave_0: left allmulticast mode
==================================================================
BUG: KCSAN: data-race in data_push_tail / vsnprintf

write to 0xffffffff893a3f16 of 41 bytes by task 12 on cpu 1:
 vsnprintf+0x2ce/0x860 lib/vsprintf.c:2899
 vscnprintf+0x41/0x90 lib/vsprintf.c:3013
 printk_sprint+0x30/0x2e0 kernel/printk/printk.c:2222
 vprintk_store+0x57b/0x910 kernel/printk/printk.c:2364
 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
 bio_check_eod block/blk-core.c:566 [inline]
 submit_bio_noacct+0x8c7/0x9b0 block/blk-core.c:806
 submit_bio+0x2a4/0x2c0 block/blk-core.c:926
 mpage_bio_submit_write fs/mpage.c:83 [inline]
 mpage_write_folio fs/mpage.c:594 [inline]
 mpage_writepages+0x79d/0x1310 fs/mpage.c:670
 fat_writepages+0x24/0x30 fs/fat/inode.c:200
 do_writepages+0x1c6/0x310 mm/page-writeback.c:2554
 __writeback_single_inode+0x80/0x720 fs/fs-writeback.c:1762
 writeback_sb_inodes+0x4fe/0xaf0 fs/fs-writeback.c:2054
 wb_writeback+0x25f/0x5d0 fs/fs-writeback.c:2239
 wb_do_writeback fs/fs-writeback.c:2386 [inline]
 wb_workfn+0x1a5/0x970 fs/fs-writeback.c:2426
 process_one_work kernel/workqueue.c:3276 [inline]
 process_scheduled_works+0x513/0xa10 kernel/workqueue.c:3359
 worker_thread+0x58a/0x780 kernel/workqueue.c:3440
 kthread+0x22a/0x280 kernel/kthread.c:436
 ret_from_fork+0x150/0x360 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffffffff893a3f18 of 8 bytes by task 4003 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:608 [inline]
 data_push_tail+0x100/0x470 kernel/printk/printk_ringbuffer.c:693
 data_alloc+0x11b/0x390 kernel/printk/printk_ringbuffer.c:1089
 prb_reserve+0x8d7/0xae0 kernel/printk/printk_ringbuffer.c:1724
 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
 __netdev_printk+0x310/0x370 net/core/dev.c:12954
 netdev_info+0xa6/0xd0 net/core/dev.c:13001
 netif_set_allmulti+0x14c/0x220 net/core/dev.c:9655
 dev_set_allmulti+0xcc/0x170 net/core/dev_api.c:313
 nbp_delete_promisc net/bridge/br_if.c:252 [inline]
 del_nbp+0x67/0x720 net/bridge/br_if.c:340
 br_dev_delete+0x4e/0xe0 net/bridge/br_if.c:386
 br_net_exit_rtnl+0x92/0xf0 net/bridge/br.c:414
 ops_exit_rtnl_list net/core/net_namespace.c:181 [inline]
 ops_undo_list+0x1be/0x420 net/core/net_namespace.c:248
 cleanup_net+0x37c/0x5b0 net/core/net_namespace.c:704
 process_one_work kernel/workqueue.c:3276 [inline]
 process_scheduled_works+0x513/0xa10 kernel/workqueue.c:3359
 worker_thread+0x58a/0x780 kernel/workqueue.c:3440
 kthread+0x22a/0x280 kernel/kthread.c:436
 ret_from_fork+0x150/0x360 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x00000000ffffe653 -> 0x6f742074706d6574

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4003 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: netns cleanup_net
==================================================================
bridge_slave_0: left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
bond0 (unregistering): (slave bond_slave_0): Releasing backup interface
bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
bond0 (unregistering): Released all slaves
hsr_slave_0: left promiscuous mode
hsr_slave_1: left promiscuous mode
batman_adv: batadv0: Interface deactivated: batadv_slave_0
batman_adv: batadv0: Removing interface: batadv_slave_0
batman_adv: batadv0: Interface deactivated: batadv_slave_1
batman_adv: batadv0: Removing interface: batadv_slave_1
veth1_macvtap: left promiscuous mode
veth0_macvtap: left promiscuous mode
veth1_vlan: left promiscuous mode
veth0_vlan: left promiscuous mode
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed
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