[moderation] [exfat?] KCSAN: data-race in generic_write_end / next_uptodate_folio (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c2d5304e6c64 Merge tag 'platform-drivers-x86-v6.7-2' of gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=144db8c8e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=8c1151391aefc0c3
dashboard link: https://syzkaller.appspot.com/bug?extid=328efd1e03a5bcf56db9
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [hiro...@mail.parknet.co.jp linki...@kernel.org linux-...@vger.kernel.org linux-...@vger.kernel.org sj155...@samsung.com]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/40c3b752a9c1/disk-c2d5304e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6ab3363b9f46/vmlinux-c2d5304e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e1685e2593f6/bzImage-c2d5304e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+328efd...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in generic_write_end / next_uptodate_folio

write to 0xffff88813af6ee60 of 8 bytes by task 7850 on cpu 1:
i_size_write include/linux/fs.h:932 [inline]
generic_write_end+0x94/0x230 fs/buffer.c:2291
fat_write_end+0x4e/0x160 fs/fat/inode.c:244
generic_perform_write+0x267/0x410 mm/filemap.c:3929
__generic_file_write_iter+0xa1/0x120 mm/filemap.c:4013
generic_file_write_iter+0x7d/0x1c0 mm/filemap.c:4039
call_write_iter include/linux/fs.h:2020 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x48a/0x790 fs/read_write.c:584
ksys_write+0xeb/0x1a0 fs/read_write.c:637
__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 0xffff88813af6ee60 of 8 bytes by task 7871 on cpu 0:
i_size_read include/linux/fs.h:910 [inline]
next_uptodate_folio+0x5c9/0x7a0 mm/filemap.c:3408
filemap_map_pages+0x6e7/0x8d0 mm/filemap.c:3556
do_fault_around mm/memory.c:4586 [inline]
do_read_fault mm/memory.c:4619 [inline]
do_fault mm/memory.c:4762 [inline]
do_pte_missing mm/memory.c:3730 [inline]
handle_pte_fault mm/memory.c:5038 [inline]
__handle_mm_fault mm/memory.c:5179 [inline]
handle_mm_fault+0x1239/0x2dd0 mm/memory.c:5344
faultin_page mm/gup.c:956 [inline]
__get_user_pages+0x402/0xe40 mm/gup.c:1239
populate_vma_page_range mm/gup.c:1677 [inline]
__mm_populate+0x216/0x330 mm/gup.c:1786
mm_populate include/linux/mm.h:3379 [inline]
vm_mmap_pgoff+0x1a7/0x240 mm/util.c:561
ksys_mmap_pgoff+0x2b8/0x330 mm/mmap.c:1425
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: 0x0000000000fab000 -> 0x0000000000fac000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7871 Comm: syz-executor.5 Not tainted 6.7.0-rc2-syzkaller-00014-gc2d5304e6c64 #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.