[moderation] [mm?] KCSAN: data-race in __anon_vma_prepare / handle_mm_fault (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 33cc938e65a9 Linux 6.7-rc4
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16f4d9e2e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=ac34c1f29a8029df
dashboard link: https://syzkaller.appspot.com/bug?extid=a50edd0826ceda438486
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [ak...@linux-foundation.org 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/6a0655688b57/disk-33cc938e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/89a66df4cc89/vmlinux-33cc938e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/621e82bbfa03/bzImage-33cc938e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a50edd...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __anon_vma_prepare / handle_mm_fault

write to 0xffff888103d20460 of 8 bytes by task 584 on cpu 1:
__anon_vma_prepare+0x147/0x2b0 mm/rmap.c:214
anon_vma_prepare include/linux/rmap.h:159 [inline]
do_anonymous_page mm/memory.c:4169 [inline]
do_pte_missing mm/memory.c:3728 [inline]
handle_pte_fault mm/memory.c:5038 [inline]
__handle_mm_fault mm/memory.c:5179 [inline]
handle_mm_fault+0x224c/0x2dd0 mm/memory.c:5344
do_user_addr_fault arch/x86/mm/fault.c:1413 [inline]
handle_page_fault arch/x86/mm/fault.c:1505 [inline]
exc_page_fault+0x2f7/0x6c0 arch/x86/mm/fault.c:1561
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

read to 0xffff888103d20460 of 8 bytes by task 593 on cpu 0:
anon_vma_prepare include/linux/rmap.h:156 [inline]
do_anonymous_page mm/memory.c:4169 [inline]
do_pte_missing mm/memory.c:3728 [inline]
handle_pte_fault mm/memory.c:5038 [inline]
__handle_mm_fault mm/memory.c:5179 [inline]
handle_mm_fault+0xeb8/0x2dd0 mm/memory.c:5344
do_user_addr_fault arch/x86/mm/fault.c:1413 [inline]
handle_page_fault arch/x86/mm/fault.c:1505 [inline]
exc_page_fault+0x2f7/0x6c0 arch/x86/mm/fault.c:1561
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
rep_movs_alternative+0x33/0x70 arch/x86/lib/copy_user_64.S:57
copy_user_generic arch/x86/include/asm/uaccess_64.h:112 [inline]
raw_copy_to_user arch/x86/include/asm/uaccess_64.h:133 [inline]
_copy_to_user+0x77/0x90 lib/usercopy.c:41
copy_to_user include/linux/uaccess.h:191 [inline]
__do_sys_sched_getaffinity kernel/sched/core.c:8499 [inline]
__se_sys_sched_getaffinity kernel/sched/core.c:8481 [inline]
__x64_sys_sched_getaffinity+0x87/0xc0 kernel/sched/core.c:8481
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: 0x0000000000000000 -> 0xffff888103ff9340

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 593 Comm: syz-executor.2 Not tainted 6.7.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================


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