syzbot

EXT4-fs (loop2): stripe (5) is not aligned with cluster size (16), stripe is disabled
==================================================================
BUG: KCSAN: data-race in data_alloc / data_push_tail

write to 0xffffffff88b8fab0 of 8 bytes by task 3411 on cpu 1:
 data_alloc+0x216/0x2c0 kernel/printk/printk_ringbuffer.c:1082
 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x53f/0x810 kernel/printk/printk.c:2301
 vprintk_emit+0x15e/0x680 kernel/printk/printk.c:2383
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2422
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:68
 _printk+0x7a/0xa0 kernel/printk/printk.c:2432
 __netdev_printk+0x2d1/0x3e0 net/core/dev.c:11821
 netdev_info+0x99/0xc0 net/core/dev.c:11868
 __dev_set_promiscuity+0x165/0x340 net/core/dev.c:8630
 dev_set_promiscuity+0x3b/0x90 net/core/dev.c:8668
 nbp_delete_promisc net/bridge/br_if.c:254 [inline]
 del_nbp+0xc3/0x770 net/bridge/br_if.c:340
 br_dev_delete+0x4e/0xe0 net/bridge/br_if.c:386
 br_net_exit_batch_rtnl+0xca/0x170 net/bridge/br.c:369
 cleanup_net+0x3d9/0x810 net/core/net_namespace.c:619
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3310
 worker_thread+0x51d/0x6f0 kernel/workqueue.c:3391
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffffffff88b8fab0 of 8 bytes by task 6883 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:594 [inline]
 data_push_tail+0x102/0x430 kernel/printk/printk_ringbuffer.c:679
 data_alloc+0xbe/0x2c0 kernel/printk/printk_ringbuffer.c:1054
 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x53f/0x810 kernel/printk/printk.c:2301
 vprintk_emit+0x15e/0x680 kernel/printk/printk.c:2383
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2422
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:68
 _printk+0x7a/0xa0 kernel/printk/printk.c:2432
 __ext4_msg+0x18e/0x1a0 fs/ext4/super.c:991
 __ext4_fill_super fs/ext4/super.c:5303 [inline]
 ext4_fill_super+0x25c2/0x3a10 fs/ext4/super.c:5686
 get_tree_bdev+0x256/0x2e0 fs/super.c:1635
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5718
 vfs_get_tree+0x56/0x1e0 fs/super.c:1800
 do_new_mount+0x227/0x690 fs/namespace.c:3507
 path_mount+0x49b/0xb30 fs/namespace.c:3834
 do_mount fs/namespace.c:3847 [inline]
 __do_sys_mount fs/namespace.c:4057 [inline]
 __se_sys_mount+0x27c/0x2d0 fs/namespace.c:4034
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4034
 x64_sys_call+0x203e/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000ffffe19b -> 0x00000000ffffee94

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 6883 Comm: syz.2.1222 Not tainted 6.12.0-rc5-syzkaller-00063-g0fc810ae3ae1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================
EXT4-fs warning (device loop2): ext4_multi_mount_protect:398: Unable to create kmmpd thread for loop2.