Message-ID: <680382c0.050a0220.297747.001b.GAE@google.com>
Date: Sat, 19 Apr 2025 04:02:24 -0700
From: syzbot <syzbot+c535cfdd86331295512d@...kaller.appspotmail.com>
To: jlbec@...lplan.org, joseph.qi@...ux.alibaba.com, 
	linux-kernel@...r.kernel.org, mark@...heh.com, ocfs2-devel@...ts.linux.dev, 
	syzkaller-bugs@...glegroups.com
Subject: [syzbot] [ocfs2?] possible deadlock in ocfs2_try_to_free_truncate_log (2)

Hello,

syzbot found the following issue on:

HEAD commit:    834a4a689699 Merge tag 'for-linus' of git://git.kernel.org..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=171ff398580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=a972ee73c2fcf8ca
dashboard link: https://syzkaller.appspot.com/bug?extid=c535cfdd86331295512d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-834a4a68.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4454365a3050/vmlinux-834a4a68.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2d99dbd9f6f4/bzImage-834a4a68.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c535cfdd86331295512d@...kaller.appspotmail.com

loop0: detected capacity change from 0 to 32768
=======================================================
WARNING: The mand mount option has been deprecated and
         and is ignored by this kernel. Remove the mand
         option from the mount to silence this warning.
=======================================================
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
netlink: 'syz.0.0': attribute type 15 has an invalid length.
(syz.0.0,5322,0):ocfs2_dio_end_io:2398 ERROR: Direct IO failed, bytes = -28
============================================
WARNING: possible recursive locking detected
6.15.0-rc2-syzkaller-00037-g834a4a689699 #0 Not tainted
--------------------------------------------
syz.0.0/5322 is trying to acquire lock:
ffff888045d83480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
ffff888045d83480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: ocfs2_try_to_free_truncate_log+0xd8/0x430 fs/ocfs2/alloc.c:6132

but task is already holding lock:
ffff888045d83480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
ffff888045d83480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: ocfs2_defrag_extent fs/ocfs2/move_extents.c:247 [inline]
ffff888045d83480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: __ocfs2_move_extents_range+0x1540/0x4470 fs/ocfs2/move_extents.c:857

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6);
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

5 locks held by syz.0.0/5322:
 #0: ffff88803ee5c420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write_file+0x5e/0x200 fs/namespace.c:600
 #1: ffff888045d842c0 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
 #1: ffff888045d842c0 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: ocfs2_move_extents+0x1c7/0xac0 fs/ocfs2/move_extents.c:905
 #2: ffff888045d83f60 (&oi->ip_alloc_sem){++++}-{4:4}, at: ocfs2_move_extents+0x3cd/0xac0 fs/ocfs2/move_extents.c:925
 #3: ffff888045d7ed80 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
 #3: ffff888045d7ed80 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{4:4}, at: ocfs2_reserve_suballoc_bits+0x18d/0x4f30 fs/ocfs2/suballoc.c:786
 #4: ffff888045d83480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
 #4: ffff888045d83480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: ocfs2_defrag_extent fs/ocfs2/move_extents.c:247 [inline]
 #4: ffff888045d83480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{4:4}, at: __ocfs2_move_extents_range+0x1540/0x4470 fs/ocfs2/move_extents.c:857

stack backtrace:
CPU: 0 UID: 0 PID: 5322 Comm: syz.0.0 Not tainted 6.15.0-rc2-syzkaller-00037-g834a4a689699 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_deadlock_bug+0x2be/0x2d0 kernel/locking/lockdep.c:3042
 check_deadlock kernel/locking/lockdep.c:3094 [inline]
 validate_chain+0x928/0x24e0 kernel/locking/lockdep.c:3896
 __lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235
 lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866
 down_write+0x9c/0x220 kernel/locking/rwsem.c:1577
 inode_lock include/linux/fs.h:867 [inline]
 ocfs2_try_to_free_truncate_log+0xd8/0x430 fs/ocfs2/alloc.c:6132
 ocfs2_reserve_clusters_with_limit+0x4ec/0xb60 fs/ocfs2/suballoc.c:1184
 ocfs2_defrag_extent fs/ocfs2/move_extents.c:266 [inline]
 __ocfs2_move_extents_range+0x19c8/0x4470 fs/ocfs2/move_extents.c:857
 ocfs2_move_extents+0x3f0/0xac0 fs/ocfs2/move_extents.c:927
 ocfs2_ioctl_move_extents+0x61c/0x840 fs/ocfs2/move_extents.c:1053
 ocfs2_ioctl+0x19b/0x7f0 fs/ocfs2/ioctl.c:946
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe8d0d8d169
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe8d1b27038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fe8d0fa5fa0 RCX: 00007fe8d0d8d169
RDX: 00002000000000c0 RSI: 0000000040406f06 RDI: 0000000000000004
RBP: 00007fe8d0e0e990 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe8d0fa5fa0 R15: 00007ffc184f1808
 </TASK>


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