[moderation] [fs?] KCSAN: data-race in do_writev / do_writev (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f016f7547aee Merge tag 'gpio-fixes-for-v6.7-rc8' of git://..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16451029e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=4da1e2da456c3a7d
dashboard link: https://syzkaller.appspot.com/bug?extid=c31a690dc2fc228109f1
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [bra...@kernel.org linux-...@vger.kernel.org linux-...@vger.kernel.org vi...@zeniv.linux.org.uk]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e9b1b541fff3/disk-f016f754.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/bdb2cd0b408d/vmlinux-f016f754.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a2b71015010c/bzImage-f016f754.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c31a69...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in do_writev / do_writev

write to 0xffff888133e87f40 of 8 bytes by task 28885 on cpu 1:
do_writev+0x12b/0x220 fs/read_write.c:978
__do_sys_writev fs/read_write.c:1049 [inline]
__se_sys_writev fs/read_write.c:1046 [inline]
__x64_sys_writev+0x45/0x50 fs/read_write.c:1046
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888133e87f40 of 8 bytes by task 28891 on cpu 0:
do_writev+0xb3/0x220 fs/read_write.c:973
__do_sys_writev fs/read_write.c:1049 [inline]
__se_sys_writev fs/read_write.c:1046 [inline]
__x64_sys_writev+0x45/0x50 fs/read_write.c:1046
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000000000000000 -> 0x0000000000001279

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 28891 Comm: syz-executor.0 Not tainted 6.7.0-rc7-syzkaller-00041-gf016f7547aee #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.