[moderation] [mm?] KCSAN: data-race in copy_mm / vm_stat_account

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 691d401c7e0e Merge tag 'spi-fix-v6.18-rc3' of git://git.ke..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=176e6e14580000
kernel config: https://syzkaller.appspot.com/x/.config?x=d2e0bc0ae94545f7
dashboard link: https://syzkaller.appspot.com/bug?extid=f8b7cc0049cc45632157
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
CC: [Liam.H...@oracle.com ak...@linux-foundation.org ja...@google.com linux-...@vger.kernel.org linu...@kvack.org lorenzo...@oracle.com pfal...@suse.de vba...@suse.cz]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8b92bcdac26e/disk-691d401c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/c784fc7b340f/vmlinux-691d401c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/112e460b800c/bzImage-691d401c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f8b7cc...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in copy_mm / vm_stat_account

read-write to 0xffff88811a085200 of 8 bytes by task 6378 on cpu 0:
vm_stat_account+0xcc/0x110 mm/mmap.c:1358
mprotect_fixup+0x506/0x570 mm/mprotect.c:849
do_mprotect_pkey+0x6d6/0x980 mm/mprotect.c:990
__do_sys_mprotect mm/mprotect.c:1011 [inline]
__se_sys_mprotect mm/mprotect.c:1008 [inline]
__x64_sys_mprotect+0x48/0x60 mm/mprotect.c:1008
x64_sys_call+0x2752/0x3000 arch/x86/include/generated/asm/syscalls_64.h:11
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88811a085080 of 1408 bytes by task 6392 on cpu 1:
dup_mm kernel/fork.c:1483 [inline]
copy_mm+0xe2/0x370 kernel/fork.c:1541
copy_process+0xd08/0x2000 kernel/fork.c:2181
kernel_clone+0x16c/0x5c0 kernel/fork.c:2609
__do_sys_clone kernel/fork.c:2750 [inline]
__se_sys_clone kernel/fork.c:2734 [inline]
__x64_sys_clone+0xe6/0x120 kernel/fork.c:2734
x64_sys_call+0x119c/0x3000 arch/x86/include/generated/asm/syscalls_64.h:57
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 6392 Comm: syz.3.646 Not tainted syzkaller #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
==================================================================


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