[moderation] [fs?] KCSAN: data-race in __should_fail_alloc_page / debugfs_write_file_bool

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: d8ec19857b09 Merge tag 'net-6.10-rc2' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10251dd6980000
kernel config: https://syzkaller.appspot.com/x/.config?x=b639694183430f97
dashboard link: https://syzkaller.appspot.com/bug?extid=5eb7efe76f46bca6bd71
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [gre...@linuxfoundation.org linux-...@vger.kernel.org linux-...@vger.kernel.org raf...@kernel.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4c525cb10506/disk-d8ec1985.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5d3c75ffceb2/vmlinux-d8ec1985.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5a992c1884ee/bzImage-d8ec1985.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5eb7ef...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __should_fail_alloc_page / debugfs_write_file_bool

write to 0xffffffff86183ea8 of 1 bytes by task 3088 on cpu 0:
debugfs_write_file_bool+0xbd/0x160 fs/debugfs/file.c:911
vfs_write+0x28b/0x900 fs/read_write.c:588
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
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

read to 0xffffffff86183ea8 of 1 bytes by task 3089 on cpu 1:
__should_fail_alloc_page+0x57/0x110 mm/fail_page_alloc.c:32
prepare_alloc_pages mm/page_alloc.c:4433 [inline]
__alloc_pages_noprof+0x109/0x360 mm/page_alloc.c:4649
alloc_pages_mpol_noprof+0xb1/0x1e0 mm/mempolicy.c:2265
alloc_pages_noprof+0xe1/0x100 mm/mempolicy.c:2336
get_free_pages_noprof+0xc/0x30 mm/page_alloc.c:4707
_pgd_alloc arch/x86/mm/pgtable.c:423 [inline]
pgd_alloc+0x22/0x170 arch/x86/mm/pgtable.c:439
mm_alloc_pgd kernel/fork.c:796 [inline]
mm_init+0x372/0x6f0 kernel/fork.c:1295
mm_alloc+0x81/0xa0 kernel/fork.c:1335
bprm_mm_init fs/exec.c:385 [inline]
alloc_bprm+0x1c8/0x5e0 fs/exec.c:1599
do_execveat_common+0x138/0x7d0 fs/exec.c:1949
do_execve fs/exec.c:2072 [inline]
__do_sys_execve fs/exec.c:2148 [inline]
__se_sys_execve fs/exec.c:2143 [inline]
__x64_sys_execve+0x5a/0x70 fs/exec.c:2143
x64_sys_call+0x1378/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:60
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: 0x01 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3089 Comm: syz-fuzzer Not tainted 6.10.0-rc1-syzkaller-00104-gd8ec19857b09 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
==================================================================


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