[moderation] [exfat?] KCSAN: data-race in __mark_inode_dirty / writeback_single_inode (8)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 0450d2083be6 Merge tag '6.10-rc-smb-fix' of git://git.samb..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=140500ec980000
kernel config: https://syzkaller.appspot.com/x/.config?x=9cea9d6e22e152b5
dashboard link: https://syzkaller.appspot.com/bug?extid=cca012716cd96d0383f7
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/04c015715988/disk-0450d208.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/93f908c0c5bd/vmlinux-0450d208.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ead896346b5c/bzImage-0450d208.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+cca012...@syzkaller.appspotmail.com

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

write to 0xffff88810d94dc78 of 8 bytes by task 5335 on cpu 1:
writeback_single_inode+0x10e/0x4a0 fs/fs-writeback.c:1769
sync_inode_metadata+0x5c/0x90 fs/fs-writeback.c:2842
__generic_file_fsync+0xf9/0x140 fs/libfs.c:1527
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:2811 [inline]
generic_file_write_iter+0x191/0x1d0 mm/filemap.c:4099
call_write_iter include/linux/fs.h:2120 [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:1362 [inline]
__se_sys_sendfile64 fs/read_write.c:1348 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
x64_sys_call+0x2c67/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:41
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88810d94dc78 of 8 bytes by task 5327 on cpu 0:
__mark_inode_dirty+0x19f/0x7e0 fs/fs-writeback.c:2508
mark_inode_dirty_sync include/linux/fs.h:2426 [inline]
vfs_fsync_range+0xef/0x140 fs/sync.c:187
generic_write_sync include/linux/fs.h:2811 [inline]
generic_file_write_iter+0x191/0x1d0 mm/filemap.c:4099
call_write_iter include/linux/fs.h:2120 [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:1362 [inline]
__se_sys_sendfile64 fs/read_write.c:1348 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
x64_sys_call+0x2c67/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:41
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000007 -> 0x0000000000000084

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5327 Comm: syz-executor.4 Not tainted 6.9.0-syzkaller-08995-g0450d2083be6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
==================================================================


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