[moderation] [ext4?] KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 815fb87b7530 Merge tag 'pm-6.7-rc4' of git://git.kernel.or..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1672f254e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=efc18f367a3f97fa
dashboard link: https://syzkaller.appspot.com/bug?extid=1b83c34d0a59b30a2657
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/98392298dffb/disk-815fb87b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4acd42758037/vmlinux-815fb87b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c9706d8d14f0/bzImage-815fb87b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1b83c3...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit

read-write to 0xffff888237d4c100 of 8 bytes by task 15032 on cpu 1:
instrument_read_write include/linux/instrumented.h:55 [inline]
__instrument_read_write_bitop include/asm-generic/bitops/instrumented-non-atomic.h:84 [inline]
___test_and_clear_bit include/asm-generic/bitops/instrumented-non-atomic.h:114 [inline]
__test_and_clear_bit_le+0x31/0x50 include/asm-generic/bitops/le.h:61
ext4_free_inode+0x3ec/0x810 fs/ext4/ialloc.c:316
ext4_evict_inode+0xb1e/0xdc0 fs/ext4/inode.c:303
evict+0x1aa/0x410 fs/inode.c:666
iput_final fs/inode.c:1777 [inline]
iput+0x42c/0x5b0 fs/inode.c:1803
do_unlinkat+0x282/0x4c0 fs/namei.c:4389
__do_sys_unlink fs/namei.c:4430 [inline]
__se_sys_unlink fs/namei.c:4428 [inline]
__x64_sys_unlink+0x30/0x40 fs/namei.c:4428
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

read to 0xffff888237d4c100 of 8 bytes by task 3098 on cpu 0:
_find_next_zero_bit+0x94/0xf0 lib/find_bit.c:198
find_next_zero_bit include/linux/find.h:186 [inline]
find_next_zero_bit_le include/linux/find.h:485 [inline]
find_inode_bit+0xae/0x320 fs/ext4/ialloc.c:724
__ext4_new_inode+0xce0/0x2270 fs/ext4/ialloc.c:1064
ext4_mkdir+0x27f/0x740 fs/ext4/namei.c:3016
vfs_mkdir+0x1ef/0x2f0 fs/namei.c:4106
do_mkdirat+0x12f/0x2a0 fs/namei.c:4129
__do_sys_mkdirat fs/namei.c:4144 [inline]
__se_sys_mkdirat fs/namei.c:4142 [inline]
__x64_sys_mkdirat+0x50/0x60 fs/namei.c:4142
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: 0x000004aa8dddffdf -> 0x000004aa8d59ffdf

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3098 Comm: syz-executor.1 Not tainted 6.7.0-rc3-syzkaller-00284-g815fb87b7530 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================


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[syzbot]

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