[moderation] [fs?] KCSAN: data-race in ksys_write / ksys_write (11)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2cc14f52aeb7 Linux 6.7-rc3
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1197afa4e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=585869067cd7ce59
dashboard link: https://syzkaller.appspot.com/bug?extid=c40eb8eed5d66937e38d
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/baa9e55a0f41/disk-2cc14f52.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5aa402127494/vmlinux-2cc14f52.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6ee6f93940bb/bzImage-2cc14f52.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c40eb8...@syzkaller.appspotmail.com

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

write to 0xffff888136e7d240 of 8 bytes by task 3229 on cpu 1:
ksys_write+0x11e/0x1a0 fs/read_write.c:639
__do_sys_write fs/read_write.c:649 [inline]
__se_sys_write fs/read_write.c:646 [inline]
__x64_sys_write+0x42/0x50 fs/read_write.c:646
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888136e7d240 of 8 bytes by task 3230 on cpu 0:
ksys_write+0xad/0x1a0 fs/read_write.c:634
__do_sys_write fs/read_write.c:649 [inline]
__se_sys_write fs/read_write.c:646 [inline]
__x64_sys_write+0x42/0x50 fs/read_write.c:646
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x000000000000077d -> 0x00000000000007bc

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3230 Comm: syz-executor.4 Not tainted 6.7.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================


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[syzbot]

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