[moderation] [mm?] KCSAN: data-race in getrusage / zap_page_range_single

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3ba7dfb8da62 Merge tag 'rcu-next-v6.15' of git://git.kerne..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1647c804580000
kernel config: https://syzkaller.appspot.com/x/.config?x=79f1cf4142160c34
dashboard link: https://syzkaller.appspot.com/bug?extid=e47c1ad6a08dcb25ccd1
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [ak...@linux-foundation.org hu...@google.com linux-...@vger.kernel.org linu...@kvack.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/dd40b872cca9/disk-3ba7dfb8.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/86a3a241fb7d/vmlinux-3ba7dfb8.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1ce46917915c/bzImage-3ba7dfb8.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e47c1a...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in getrusage / zap_page_range_single

write to 0xffff88812eb65378 of 8 bytes by task 21893 on cpu 0:
update_hiwater_rss include/linux/mm.h:2675 [inline]
zap_page_range_single+0x1a0/0x2f0 mm/memory.c:2022
unmap_mapping_range_vma mm/memory.c:3846 [inline]
unmap_mapping_range_tree mm/memory.c:3863 [inline]
unmap_mapping_pages mm/memory.c:3929 [inline]
unmap_mapping_range+0x15c/0x1a0 mm/memory.c:3966
shmem_fallocate+0x278/0x860 mm/shmem.c:3695
vfs_fallocate+0x368/0x3b0 fs/open.c:338
madvise_remove mm/madvise.c:1034 [inline]
madvise_vma_behavior mm/madvise.c:1269 [inline]
madvise_walk_vmas mm/madvise.c:1511 [inline]
do_madvise+0x14dd/0x2ad0 mm/madvise.c:1698
__do_sys_madvise mm/madvise.c:1714 [inline]
__se_sys_madvise mm/madvise.c:1712 [inline]
__x64_sys_madvise+0x61/0x70 mm/madvise.c:1712
x64_sys_call+0x23b8/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:29
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 0xffff88812eb65378 of 8 bytes by task 21873 on cpu 1:
get_mm_hiwater_rss include/linux/mm.h:2662 [inline]
setmax_mm_hiwater_rss include/linux/mm.h:2692 [inline]
getrusage+0xa15/0xb70 kernel/sys.c:1876
io_sq_thread+0x5de/0x10e0 io_uring/sqpoll.c:310
ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0x00000000000016ef -> 0x00000000000021ef

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 21873 Comm: iou-sqp-21872 Not tainted 6.14.0-syzkaller-00685-g3ba7dfb8da62 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
==================================================================


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[syzbot]

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