[moderation] [exfat?] KCSAN: data-race in __mark_inode_dirty / __mark_inode_dirty (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 18d46e76d7c2 Merge tag 'for-6.7-rc3-tag' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16e261c2e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=585869067cd7ce59
dashboard link: https://syzkaller.appspot.com/bug?extid=bf3ff96e3400b3ac6979
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/4ff85d0f0b28/disk-18d46e76.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/37f6de14cbea/vmlinux-18d46e76.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d94866b08798/bzImage-18d46e76.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+bf3ff9...@syzkaller.appspotmail.com

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

write to 0xffff888132f39c78 of 8 bytes by task 6031 on cpu 1:
__mark_inode_dirty+0x250/0x7d0 fs/fs-writeback.c:2483
fat_update_time+0x1fe/0x210 fs/fat/misc.c:357
inode_update_time fs/inode.c:1955 [inline]
touch_atime+0x147/0x2d0 fs/inode.c:2028
file_accessed include/linux/fs.h:2360 [inline]
filemap_splice_read+0x76e/0x7f0 mm/filemap.c:2916
vfs_splice_read fs/splice.c:993 [inline]
splice_direct_to_actor+0x28c/0x690 fs/splice.c:1069
do_splice_direct+0x10d/0x190 fs/splice.c:1194
do_sendfile+0x3c4/0x980 fs/read_write.c:1254
__do_sys_sendfile64 fs/read_write.c:1322 [inline]
__se_sys_sendfile64 fs/read_write.c:1308 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
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 0xffff888132f39c78 of 8 bytes by task 6032 on cpu 0:
__mark_inode_dirty+0x58/0x7d0 fs/fs-writeback.c:2434
fat_update_time+0x1fe/0x210 fs/fat/misc.c:357
inode_update_time fs/inode.c:1955 [inline]
touch_atime+0x147/0x2d0 fs/inode.c:2028
file_accessed include/linux/fs.h:2360 [inline]
generic_file_read_iter+0x1f7/0x330 mm/filemap.c:2747
call_read_iter include/linux/fs.h:2014 [inline]
copy_splice_read+0x26b/0x4b0 fs/splice.c:364
vfs_splice_read fs/splice.c:992 [inline]
splice_direct_to_actor+0x2aa/0x690 fs/splice.c:1069
do_splice_direct+0x10d/0x190 fs/splice.c:1194
do_sendfile+0x3c4/0x980 fs/read_write.c:1254
__do_sys_sendfile64 fs/read_write.c:1322 [inline]
__se_sys_sendfile64 fs/read_write.c:1308 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
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 -> 0x0000000000000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 6032 Comm: syz-executor.5 Not tainted 6.7.0-rc3-syzkaller-00024-g18d46e76d7c2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================


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