[moderation] [ext4?] KCSAN: data-race in __mark_inode_dirty / writeback_sb_inodes (14)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4652b8e4f3ff Merge tag '6.7-rc-ksmbd-server-fixes' of git:..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=153e65a0e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=561f2d77dae76e1b
dashboard link: https://syzkaller.appspot.com/bug?extid=956afd0db40b79dae18d
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [adilger...@dilger.ca linux...@vger.kernel.org linux-...@vger.kernel.org linux-...@vger.kernel.org ty...@mit.edu]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6404911ced49/disk-4652b8e4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/811b8c84dc1a/vmlinux-4652b8e4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b68ddd8f7b64/bzImage-4652b8e4.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+956afd...@syzkaller.appspotmail.com

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

write to 0xffff8881065a3d10 of 8 bytes by task 1537 on cpu 0:
writeback_sb_inodes+0x2da/0xad0 fs/fs-writeback.c:1905
wb_writeback+0x252/0x6e0 fs/fs-writeback.c:2092
wb_do_writeback fs/fs-writeback.c:2239 [inline]
wb_workfn+0x1a8/0x8d0 fs/fs-writeback.c:2279
process_one_work kernel/workqueue.c:2630 [inline]
process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
worker_thread+0x525/0x730 kernel/workqueue.c:2784
kthread+0x1d7/0x210 kernel/kthread.c:388
ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

read to 0xffff8881065a3d10 of 8 bytes by task 3592 on cpu 1:
__mark_inode_dirty+0x58/0x7d0 fs/fs-writeback.c:2434
mark_inode_dirty include/linux/fs.h:2306 [inline]
dquot_alloc_space include/linux/quotaops.h:320 [inline]
dquot_alloc_block include/linux/quotaops.h:337 [inline]
ext4_mb_new_blocks+0x103e/0x21e0 fs/ext4/mballoc.c:6153
ext4_ext_map_blocks+0x1086/0x3640 fs/ext4/extents.c:4285
ext4_map_blocks+0x704/0xf60 fs/ext4/inode.c:621
ext4_alloc_file_blocks+0x285/0x6f0 fs/ext4/extents.c:4462
ext4_fallocate+0x77e/0x1190 fs/ext4/extents.c:4757
vfs_fallocate+0x378/0x3e0 fs/open.c:324
do_vfs_ioctl+0x12e6/0x13a0 fs/ioctl.c:850
__do_sys_ioctl fs/ioctl.c:869 [inline]
__se_sys_ioctl+0x81/0x140 fs/ioctl.c:857
__x64_sys_ioctl+0x43/0x50 fs/ioctl.c:857
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: 0x0000000000020007 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3592 Comm: syz-executor.1 Not tainted 6.6.0-syzkaller-10396-g4652b8e4f3ff #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
==================================================================


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