[moderation] [ext4?] KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 6764c317b6bb Merge tag 'scsi-fixes' of git://git.kernel.or..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16c14a28180000
kernel config: https://syzkaller.appspot.com/x/.config?x=4aab723d3dfffc44
dashboard link: https://syzkaller.appspot.com/bug?extid=5a6d27fe82de9894417a
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/9ed1efd40546/disk-6764c317.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/69b46a73fc4f/vmlinux-6764c317.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f20d9a948904/bzImage-6764c317.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5a6d27...@syzkaller.appspotmail.com

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

read-write to 0xffff888237c500f8 of 8 bytes by task 14490 on cpu 0:
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+0xb20/0xdc0 fs/ext4/inode.c:303
evict+0x1aa/0x410 fs/inode.c:665
iput_final fs/inode.c:1739 [inline]
iput+0x42c/0x5c0 fs/inode.c:1765
d_delete_notify include/linux/fsnotify.h:301 [inline]
vfs_rmdir+0x274/0x2f0 fs/namei.c:4218
do_rmdir+0x194/0x320 fs/namei.c:4264
__do_sys_unlinkat fs/namei.c:4440 [inline]
__se_sys_unlinkat fs/namei.c:4434 [inline]
__x64_sys_unlinkat+0xa4/0xb0 fs/namei.c:4434
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888237c500f8 of 8 bytes by task 8073 on cpu 1:
_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_symlink+0x242/0x590 fs/ext4/namei.c:3396
vfs_symlink+0xc2/0x1a0 fs/namei.c:4480
do_symlinkat+0xe3/0x340 fs/namei.c:4506
__do_sys_symlinkat fs/namei.c:4522 [inline]
__se_sys_symlinkat fs/namei.c:4519 [inline]
__x64_sys_symlinkat+0x62/0x70 fs/namei.c:4519
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x00000003fecbbbff -> 0x00000003f6cbbfff

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8073 Comm: syz-executor.0 Not tainted 6.8.0-rc2-syzkaller-00055-g6764c317b6bb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
==================================================================


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