[moderation] [exfat?] KCSAN: data-race in __mark_inode_dirty / writeback_single_inode (7)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: b3603fcb79b1 Merge tag 'dlm-6.9' of git://git.kernel.org/p..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=156ec2a5180000
kernel config: https://syzkaller.appspot.com/x/.config?x=8c3c081f20b130f6
dashboard link: https://syzkaller.appspot.com/bug?extid=d7e3435971b89bb18d71
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/b01659dc6b5e/disk-b3603fcb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e41dca2db79a/vmlinux-b3603fcb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/316b59a2f802/bzImage-b3603fcb.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d7e343...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __mark_inode_dirty / writeback_single_inode

write to 0xffff888107e8a288 of 8 bytes by task 14520 on cpu 1:
writeback_single_inode+0x10e/0x4a0 fs/fs-writeback.c:1768
sync_inode_metadata+0x5c/0x90 fs/fs-writeback.c:2833
__generic_file_fsync+0xf9/0x140 fs/libfs.c:1484
fat_file_fsync+0x4c/0x100 fs/fat/file.c:191
vfs_fsync_range+0x122/0x140 fs/sync.c:188
generic_write_sync include/linux/fs.h:2793 [inline]
generic_file_write_iter+0x191/0x1d0 mm/filemap.c:4099
call_write_iter include/linux/fs.h:2108 [inline]
iter_file_splice_write+0x5e6/0x970 fs/splice.c:743
do_splice_from fs/splice.c:941 [inline]
direct_splice_actor+0x16c/0x2c0 fs/splice.c:1164
splice_direct_to_actor+0x305/0x670 fs/splice.c:1108
do_splice_direct_actor fs/splice.c:1207 [inline]
do_splice_direct+0xd7/0x150 fs/splice.c:1233
do_sendfile+0x3b9/0x970 fs/read_write.c:1295
__do_sys_sendfile64 fs/read_write.c:1356 [inline]
__se_sys_sendfile64 fs/read_write.c:1348 [inline]
__x64_sys_sendfile64+0xbd/0x150 fs/read_write.c:1348
do_syscall_64+0xd3/0x1d0
entry_SYSCALL_64_after_hwframe+0x6d/0x75

read to 0xffff888107e8a288 of 8 bytes by task 14529 on cpu 0:
__mark_inode_dirty+0x58/0x7e0 fs/fs-writeback.c:2459
fat_update_time+0x1fe/0x210 fs/fat/misc.c:357
inode_update_time fs/inode.c:1919 [inline]
touch_atime+0x14f/0x350 fs/inode.c:1992
file_accessed include/linux/fs.h:2457 [inline]
filemap_splice_read+0x8b0/0x920 mm/filemap.c:2926
do_splice_read fs/splice.c:985 [inline]
splice_direct_to_actor+0x26c/0x670 fs/splice.c:1089
do_splice_direct_actor fs/splice.c:1207 [inline]
do_splice_direct+0xd7/0x150 fs/splice.c:1233
do_sendfile+0x3b9/0x970 fs/read_write.c:1295
__do_sys_sendfile64 fs/read_write.c:1362 [inline]
__se_sys_sendfile64 fs/read_write.c:1348 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
do_syscall_64+0xd3/0x1d0
entry_SYSCALL_64_after_hwframe+0x6d/0x75

value changed: 0x0000000000000007 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 14529 Comm: syz-executor.3 Not tainted 6.8.0-syzkaller-11567-gb3603fcb79b1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
==================================================================


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[syzbot]

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