[moderation] [serial?] KCSAN: data-race in n_tty_receive_buf_common / n_tty_write (6)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2ef5971ff345 Merge tag 'vfs-6.10-rc4.fixes' of git://git.k..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1186c44c980000
kernel config: https://syzkaller.appspot.com/x/.config?x=68336ea4b6f4fc09
dashboard link: https://syzkaller.appspot.com/bug?extid=78b6cadc25abfcbc3159
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [gre...@linuxfoundation.org jiri...@kernel.org linux-...@vger.kernel.org linux-...@vger.kernel.org]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/fe2005cec720/disk-2ef5971f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/86bdd28ca152/vmlinux-2ef5971f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/34f1c4c270f6/bzImage-2ef5971f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+78b6ca...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in n_tty_receive_buf_common / n_tty_write

write to 0xffffc90000e51020 of 8 bytes by task 15036 on cpu 1:
process_echoes drivers/tty/n_tty.c:788 [inline]
n_tty_write+0x1bc/0xb90 drivers/tty/n_tty.c:2365
iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
file_tty_write+0x386/0x690 drivers/tty/tty_io.c:1096
tty_write+0x28/0x30 drivers/tty/tty_io.c:1117
new_sync_write fs/read_write.c:497 [inline]
vfs_write+0x78f/0x900 fs/read_write.c:590
ksys_write+0xeb/0x1b0 fs/read_write.c:643
__do_sys_write fs/read_write.c:655 [inline]
__se_sys_write fs/read_write.c:652 [inline]
__x64_sys_write+0x42/0x50 fs/read_write.c:652
x64_sys_call+0x27ef/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:2


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