syzbot

udevd[17753]: inotify_add_watch(7, /dev/loop1p3, 10) failed: No such file or directory
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BUG: KCSAN: data-race in data_push_tail / string

write to 0xffffffff883e5d58 of 1 bytes by task 17548 on cpu 1:
 string_nocheck lib/vsprintf.c:650 [inline]
 string+0x16c/0x210 lib/vsprintf.c:728
 vsnprintf+0xa09/0xe30 lib/vsprintf.c:2824
 vscnprintf+0x42/0x90 lib/vsprintf.c:2930
 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2165
 vprintk_store+0x570/0x810 kernel/printk/printk.c:2279
 vprintk_emit+0x10c/0x5e0 kernel/printk/printk.c:2329
 devkmsg_emit+0x82/0xb0 kernel/printk/printk.c:722
 devkmsg_write+0x248/0x2a0 kernel/printk/printk.c:785
 do_iter_readv_writev+0x339/0x3e0
 vfs_writev+0x2e9/0x860 fs/read_write.c:971
 do_writev+0xf8/0x220 fs/read_write.c:1018
 __do_sys_writev fs/read_write.c:1091 [inline]
 __se_sys_writev fs/read_write.c:1088 [inline]
 __x64_sys_writev+0x45/0x50 fs/read_write.c:1088
 x64_sys_call+0x1eca/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff883e5d58 of 8 bytes by task 17753 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:2269
 vprintk_emit+0x10c/0x5e0 kernel/printk/printk.c:2329
 devkmsg_emit+0x82/0xb0 kernel/printk/printk.c:722
 devkmsg_write+0x248/0x2a0 kernel/printk/printk.c:785
 do_iter_readv_writev+0x339/0x3e0
 vfs_writev+0x2e9/0x860 fs/read_write.c:971
 do_writev+0xf8/0x220 fs/read_write.c:1018
 __do_sys_writev fs/read_write.c:1091 [inline]
 __se_sys_writev fs/read_write.c:1088 [inline]
 __x64_sys_writev+0x45/0x50 fs/read_write.c:1088
 x64_sys_call+0x1eca/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000100001dd6 -> 0x64615f796669746f

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 17753 Comm: udevd Tainted: G        W          6.9.0-rc3-syzkaller-00344-g8f2c057754b2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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