[moderation] [ext4?] KCSAN: data-race in has_bh_in_lru / invalidate_bh_lru (7)

Hello,

syzbot found the following issue on:

HEAD commit: 69e858e0b8b2 Merge tag 'uml-for-linus-6.14-rc1' of git://g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10b35ddf980000
kernel config: https://syzkaller.appspot.com/x/.config?x=723e332ac5000fb0
dashboard link: https://syzkaller.appspot.com/bug?extid=90985875775c771287a9
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [[email protected] [email protected] [email protected] [email protected]]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/2e629d19fccf/disk-69e858e0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/c5fd745c0d54/vmlinux-69e858e0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/00752f2dc163/bzImage-69e858e0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]

EXT4-fs error (device loop6): ext4_orphan_get:1394: comm syz.6.2586: couldn't read orphan inode 15 (err -117)
EXT4-fs (loop6): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
EXT4-fs (loop6): unmounting filesystem 00000000-0000-0000-0000-000000000000.
==================================================================
BUG: KCSAN: data-race in has_bh_in_lru / invalidate_bh_lru

write to 0xffff888237d2b9e8 of 8 bytes by task 3309 on cpu 1:
__invalidate_bh_lrus fs/buffer.c:1499 [inline]
invalidate_bh_lru+0x8b/0xf0 fs/buffer.c:1511
csd_do_func kernel/smp.c:134 [inline]
smp_call_function_many_cond+0x5ab/0xbb0 kernel/smp.c:876
on_each_cpu_cond_mask+0x3c/0x90 kernel/smp.c:1052
on_each_cpu_cond include/linux/smp.h:105 [inline]
invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1530
invalidate_bdev+0x42/0x70 block/bdev.c:100
ext4_put_super+0x571/0x810 fs/ext4/super.c:1356
generic_shutdown_super+0xe5/0x220 fs/super.c:642
kill_block_super+0x2a/0x70 fs/super.c:1710
ext4_kill_sb+0x44/0x80 fs/ext4/super.c:7368
deactivate_locked_super+0x7d/0x1c0 fs/super.c:473
deactivate_super+0x9f/0xb0 fs/super.c:506
cleanup_mnt+0x268/0x2e0 fs/namespace.c:1413
__cleanup_mnt+0x19/0x20 fs/namespace.c:1420
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 0xffff888237d2b9e8 of 8 bytes by task 10630 on cpu 0:
has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1521
smp_call_function_many_cond+0x305/0xbb0 kernel/smp.c:838
on_each_cpu_cond_mask+0x3c/0x90 kernel/smp.c:1052
on_each_cpu_cond include/linux/smp.h:105 [inline]
invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1530
invalidate_bdev+0x42/0x70 block/bdev.c:100
ext4_put_super+0x571/0x810 fs/ext4/super.c:1356
generic_shutdown_super+0xe5/0x220 fs/super.c:642
kill_block_super+0x2a/0x70 fs/super.c:1710
ext4_kill_sb+0x44/0x80 fs/ext4/super.c:7368
deactivate_locked_super+0x7d/0x1c0 fs/super.c:473
deactivate_super+0x9f/0xb0 fs/super.c:506
cleanup_mnt+0x268/0x2e0 fs/namespace.c:1413
__cleanup_mnt+0x19/0x20 fs/namespace.c:1420
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

value changed: 0xffff888106582f70 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 10630 Comm: syz.6.2586 Not tainted 6.13.0-syzkaller-09760-g69e858e0b8b2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
==================================================================


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