[moderation] [exfat?] KCSAN: data-race in dio_bio_end_io / dio_new_bio (5)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 76b6905c11fd Merge tag 'mm-hotfixes-stable-2025-03-17-20-0..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1135a44c580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f33d372c4021745
dashboard link: https://syzkaller.appspot.com/bug?extid=2afdfa962af04de7f342
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/0df5dc799e8c/disk-76b6905c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fc351dc29cd6/vmlinux-76b6905c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1e1ceec24d2e/bzImage-76b6905c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2afdfa...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in dio_bio_end_io / dio_new_bio

read-write to 0xffff888116476cd8 of 8 bytes by interrupt on cpu 0:
dio_bio_end_io+0x53/0xd0 fs/direct-io.c:387
bio_endio+0x369/0x410 block/bio.c:1548
blk_update_request+0x368/0x860 block/blk-mq.c:983
blk_mq_end_request+0x26/0x50 block/blk-mq.c:1145
lo_complete_rq+0xce/0x180 drivers/block/loop.c:395
blk_complete_reqs block/blk-mq.c:1220 [inline]
blk_done_softirq+0x74/0xb0 block/blk-mq.c:1225
handle_softirqs+0xbf/0x280 kernel/softirq.c:561
__do_softirq kernel/softirq.c:595 [inline]
invoke_softirq kernel/softirq.c:435 [inline]
__irq_exit_rcu+0x3a/0xc0 kernel/softirq.c:662
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0x73/0x80 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
__preempt_count_dec_and_test arch/x86/include/asm/preempt.h:94 [inline]
__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
_raw_spin_unlock_irq+0x2f/0x50 kernel/locking/spinlock.c:202
spin_unlock_irq include/linux/spinlock.h:401 [inline]
filemap_remove_folio+0x73/0x1f0 mm/filemap.c:256
truncate_inode_folio+0x42/0x50 mm/truncate.c:162
shmem_undo_range+0x25b/0xa70 mm/shmem.c:1108
shmem_truncate_range mm/shmem.c:1224 [inline]
shmem_evict_inode+0x14d/0x530 mm/shmem.c:1352
evict+0x2f0/0x570 fs/inode.c:796
iput_final fs/inode.c:1946 [inline]
iput+0x42a/0x5b0 fs/inode.c:1972
dentry_unlink_inode+0x24f/0x260 fs/dcache.c:440
__dentry_kill+0x18b/0x4c0 fs/dcache.c:643
dput+0x5c/0xd0 fs/dcache.c:885
__fput+0x428/0x640 fs/file_table.c:472
____fput+0x1c/0x30 fs/file_table.c:492
task_work_run+0x13a/0x1a0 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0xa8/0x120 kernel/entry/common.c:218
do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888116476cd8 of 8 bytes by task 10914 on cpu 1:
dio_bio_reap fs/direct-io.c:550 [inline]
dio_new_bio+0x249/0x460 fs/direct-io.c:669
dio_send_cur_page+0x1f2/0x7a0 fs/direct-io.c:750
submit_page_section+0x1a3/0x5b0 fs/direct-io.c:815
do_direct_IO fs/direct-io.c:1030 [inline]
__blockdev_direct_IO+0x11bb/0x1e80 fs/direct-io.c:1243
blockdev_direct_IO include/linux/fs.h:3412 [inline]
fat_direct_IO+0x10a/0x1d0 fs/fat/inode.c:281
generic_file_read_iter+0x225/0x330 mm/filemap.c:2870
copy_splice_read+0x383/0x5b0 fs/splice.c:365
do_splice_read fs/splice.c:984 [inline]
splice_direct_to_actor+0x28b/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+0x398/0x660 fs/read_write.c:1363
__do_sys_sendfile64 fs/read_write.c:1424 [inline]
__se_sys_sendfile64 fs/read_write.c:1410 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1410
x64_sys_call+0xfbd/0x2dc0 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: 0xffff8881273b2f00 -> 0xffff8881273b26c0

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 10914 Comm: syz.3.2561 Tainted: G W 6.14.0-rc7-syzkaller-00067-g76b6905c11fd #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
==================================================================


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[syzbot]

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