[moderation] [exfat?] KCSAN: data-race in __generic_file_fsync / __mark_inode_dirty (6)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 626737a5791b Merge tag 'pinctrl-v6.10-2' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13ba539c980000
kernel config: https://syzkaller.appspot.com/x/.config?x=7e87b541dc1fc960
dashboard link: https://syzkaller.appspot.com/bug?extid=ffa996b3456919dca1b7
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/ee4c67adef4f/disk-626737a5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/124b0d3318d3/vmlinux-626737a5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8acf9961638a/bzImage-626737a5.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ffa996...@syzkaller.appspotmail.com

(unnamed net_device) (uninitialized): option active_slave: mode dependency failed, not supported in mode broadcast(3)
==================================================================
BUG: KCSAN: data-race in __generic_file_fsync / __mark_inode_dirty

write to 0xffff888108042ea8 of 8 bytes by task 15446 on cpu 0:
__mark_inode_dirty+0x256/0x7e0 fs/fs-writeback.c:2517
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:2458 [inline]
filemap_splice_read+0x8b0/0x920 mm/filemap.c:2950
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+0x3ab/0x960 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+0x2c9f/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:41
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888108042ea8 of 8 bytes by task 15450 on cpu 1:
__generic_file_fsync+0x95/0x140 fs/libfs.c:1522
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:2794 [inline]
generic_file_write_iter+0x191/0x1d0 mm/filemap.c:4140
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+0x3ab/0x960 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+0x2c9f/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:41
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000000 -> 0x0000000000000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 15450 Comm: syz.4.3800 Not tainted 6.10.0-rc5-syzkaller-00012-g626737a5791b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
==================================================================


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