[moderation] [mm?] KCSAN: data-race in list_lru_add / list_lru_count_node (12)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: dc1c8034e31b minmax: simplify min()/max()/clamp() implemen..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1263299d980000
kernel config: https://syzkaller.appspot.com/x/.config?x=bc4a9b665a33d32c
dashboard link: https://syzkaller.appspot.com/bug?extid=55873bbba7a34bafdb95
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [ak...@linux-foundation.org linux-...@vger.kernel.org linu...@kvack.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/910e5b00ab64/disk-dc1c8034.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5933a268c921/vmlinux-dc1c8034.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0d2695c24ec2/bzImage-dc1c8034.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+55873b...@syzkaller.appspotmail.com

misc raw-gadget: fail, usb_gadget_register_driver returned -16
==================================================================
BUG: KCSAN: data-race in list_lru_add / list_lru_count_node

read-write to 0xffff8881068d2760 of 8 bytes by task 3255 on cpu 1:
list_lru_add+0x1f4/0x230 mm/list_lru.c:101
list_lru_add_obj+0xbb/0xd0 mm/list_lru.c:116
d_lru_add+0xa8/0xe0 fs/dcache.c:437
retain_dentry fs/dcache.c:719 [inline]
fast_dput+0x27a/0x2c0 fs/dcache.c:806
dput+0x24/0xd0 fs/dcache.c:846
__fput+0x41f/0x6f0 fs/file_table.c:430
__fput_sync+0x44/0x60 fs/file_table.c:507
__do_sys_close fs/open.c:1566 [inline]
__se_sys_close+0x101/0x1b0 fs/open.c:1551
__x64_sys_close+0x1f/0x30 fs/open.c:1551
x64_sys_call+0x2630/0x2e00 arch/x86/include/generated/asm/syscalls_64.h:4
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

read to 0xffff8881068d2760 of 8 bytes by task 4334 on cpu 0:
list_lru_count_node+0x2c/0x40 mm/list_lru.c:188
list_lru_count include/linux/list_lru.h:165 [inline]
shrink_dcache_sb+0x1a4/0x280 fs/dcache.c:1203
reconfigure_super+0x2eb/0x5b0 fs/super.c:1061
vfs_cmd_reconfigure fs/fsopen.c:263 [inline]
vfs_fsconfig_locked fs/fsopen.c:292 [inline]
__do_sys_fsconfig fs/fsopen.c:473 [inline]
__se_sys_fsconfig+0x79b/0x9c0 fs/fsopen.c:345
__x64_sys_fsconfig+0x67/0x80 fs/fsopen.c:345
x64_sys_call+0x3af/0x2e00 arch/x86/include/generated/asm/syscalls_64.h:432
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: 0x0000000000000000 -> 0x0000000000000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4334 Comm: syz.2.169 Not tainted 6.11.0-rc1-syzkaller-00004-gdc1c8034e31b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
==================================================================


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[syzbot]

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