Message-ID: <000000000000469efa0621bcd98a@google.com>
Date: Mon, 09 Sep 2024 22:07:23 -0700
From: syzbot <syzbot+ba9a789bd1f4d21fcefe@...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_xattr_set

Hello,

syzbot found the following issue on:

HEAD commit:    b831f83e40a2 Merge tag 'bpf-6.11-rc7' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12a2affb980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=660f6eb11f9c7dc5
dashboard link: https://syzkaller.appspot.com/bug?extid=ba9a789bd1f4d21fcefe
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/7bc7510fe41f/non_bootable_disk-b831f83e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ab02bf22935d/vmlinux-b831f83e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c1101078451d/bzImage-b831f83e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ba9a789bd1f4d21fcefe@...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.
======================================================
WARNING: possible circular locking dependency detected
6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 Not tainted
------------------------------------------------------
syz.0.0/5118 is trying to acquire lock:
ffff88803f583480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:800 [inline]
ffff88803f583480 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: ocfs2_xattr_set+0xe9e/0x1930 fs/ocfs2/xattr.c:3623

but task is already holding lock:
ffff88803f584e38 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_xattr_set+0x633/0x1930 fs/ocfs2/xattr.c:3584

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&oi->ip_xattr_sem){++++}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       down_read+0xb1/0xa40 kernel/locking/rwsem.c:1526
       ocfs2_init_acl+0x397/0x930 fs/ocfs2/acl.c:366
       ocfs2_mknod+0x1c05/0x2b40 fs/ocfs2/namei.c:408
       ocfs2_create+0x1ab/0x480 fs/ocfs2/namei.c:672
       lookup_open fs/namei.c:3578 [inline]
       open_last_lookups fs/namei.c:3647 [inline]
       path_openat+0x1a9a/0x3470 fs/namei.c:3883
       do_filp_open+0x235/0x490 fs/namei.c:3913
       do_sys_openat2+0x13e/0x1d0 fs/open.c:1416
       do_sys_open fs/open.c:1431 [inline]
       __do_sys_openat fs/open.c:1447 [inline]
       __se_sys_openat fs/open.c:1442 [inline]
       __x64_sys_openat+0x247/0x2a0 fs/open.c:1442
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #3 (jbd2_handle){++++}-{0:0}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       start_this_handle+0x1eb4/0x2110 fs/jbd2/transaction.c:448
       jbd2__journal_start+0x2da/0x5d0 fs/jbd2/transaction.c:505
       jbd2_journal_start+0x29/0x40 fs/jbd2/transaction.c:544
       ocfs2_start_trans+0x3c9/0x700 fs/ocfs2/journal.c:352
       ocfs2_mknod+0x150c/0x2b40 fs/ocfs2/namei.c:359
       ocfs2_create+0x1ab/0x480 fs/ocfs2/namei.c:672
       lookup_open fs/namei.c:3578 [inline]
       open_last_lookups fs/namei.c:3647 [inline]
       path_openat+0x1a9a/0x3470 fs/namei.c:3883
       do_filp_open+0x235/0x490 fs/namei.c:3913
       do_sys_openat2+0x13e/0x1d0 fs/open.c:1416
       do_sys_open fs/open.c:1431 [inline]
       __do_sys_openat fs/open.c:1447 [inline]
       __se_sys_openat fs/open.c:1442 [inline]
       __x64_sys_openat+0x247/0x2a0 fs/open.c:1442
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (&journal->j_trans_barrier){.+.+}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       down_read+0xb1/0xa40 kernel/locking/rwsem.c:1526
       ocfs2_start_trans+0x3be/0x700 fs/ocfs2/journal.c:350
       ocfs2_mknod+0x150c/0x2b40 fs/ocfs2/namei.c:359
       ocfs2_create+0x1ab/0x480 fs/ocfs2/namei.c:672
       lookup_open fs/namei.c:3578 [inline]
       open_last_lookups fs/namei.c:3647 [inline]
       path_openat+0x1a9a/0x3470 fs/namei.c:3883
       do_filp_open+0x235/0x490 fs/namei.c:3913
       do_sys_openat2+0x13e/0x1d0 fs/open.c:1416
       do_sys_open fs/open.c:1431 [inline]
       __do_sys_openat fs/open.c:1447 [inline]
       __se_sys_openat fs/open.c:1442 [inline]
       __x64_sys_openat+0x247/0x2a0 fs/open.c:1442
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (sb_internal#2){.+.+}-{0:0}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1676 [inline]
       sb_start_intwrite include/linux/fs.h:1859 [inline]
       ocfs2_start_trans+0x2b9/0x700 fs/ocfs2/journal.c:348
       ocfs2_remove_btree_range+0x8e4/0x1860 fs/ocfs2/alloc.c:5752
       ocfs2_commit_truncate+0xcca/0x2560 fs/ocfs2/alloc.c:7353
       ocfs2_truncate_file+0xd0e/0x1560 fs/ocfs2/file.c:509
       ocfs2_setattr+0x1217/0x1f50 fs/ocfs2/file.c:1208
       notify_change+0xbca/0xe90 fs/attr.c:503
       do_truncate+0x220/0x310 fs/open.c:65
       vfs_truncate+0x2e1/0x3b0 fs/open.c:111
       do_sys_truncate+0xdb/0x190 fs/open.c:134
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3133 [inline]
       check_prevs_add kernel/locking/lockdep.c:3252 [inline]
       validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
       __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       down_write+0x99/0x220 kernel/locking/rwsem.c:1579
       inode_lock include/linux/fs.h:800 [inline]
       ocfs2_xattr_set+0xe9e/0x1930 fs/ocfs2/xattr.c:3623
       __vfs_setxattr+0x468/0x4a0 fs/xattr.c:200
       __vfs_setxattr_noperm+0x12e/0x660 fs/xattr.c:234
       vfs_setxattr+0x221/0x430 fs/xattr.c:321
       do_setxattr fs/xattr.c:629 [inline]
       path_setxattr+0x37e/0x4d0 fs/xattr.c:658
       __do_sys_lsetxattr fs/xattr.c:683 [inline]
       __se_sys_lsetxattr fs/xattr.c:679 [inline]
       __x64_sys_lsetxattr+0xb8/0xd0 fs/xattr.c:679
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6 --> jbd2_handle --> &oi->ip_xattr_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&oi->ip_xattr_sem);
                               lock(jbd2_handle);
                               lock(&oi->ip_xattr_sem);
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6);

 *** DEADLOCK ***

3 locks held by syz.0.0/5118:
 #0: ffff88804ab5a420 (sb_writers#10){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
 #1: ffff88803f585100 (&sb->s_type->i_mutex_key#19){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:800 [inline]
 #1: ffff88803f585100 (&sb->s_type->i_mutex_key#19){+.+.}-{3:3}, at: vfs_setxattr+0x1e1/0x430 fs/xattr.c:320
 #2: ffff88803f584e38 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_xattr_set+0x633/0x1930 fs/ocfs2/xattr.c:3584

stack backtrace:
CPU: 0 UID: 0 PID: 5118 Comm: syz.0.0 Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0
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:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2186
 check_prev_add kernel/locking/lockdep.c:3133 [inline]
 check_prevs_add kernel/locking/lockdep.c:3252 [inline]
 validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
 down_write+0x99/0x220 kernel/locking/rwsem.c:1579
 inode_lock include/linux/fs.h:800 [inline]
 ocfs2_xattr_set+0xe9e/0x1930 fs/ocfs2/xattr.c:3623
 __vfs_setxattr+0x468/0x4a0 fs/xattr.c:200
 __vfs_setxattr_noperm+0x12e/0x660 fs/xattr.c:234
 vfs_setxattr+0x221/0x430 fs/xattr.c:321
 do_setxattr fs/xattr.c:629 [inline]
 path_setxattr+0x37e/0x4d0 fs/xattr.c:658
 __do_sys_lsetxattr fs/xattr.c:683 [inline]
 __se_sys_lsetxattr fs/xattr.c:679 [inline]
 __x64_sys_lsetxattr+0xb8/0xd0 fs/xattr.c:679
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd4c4f7cef9
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:00007fd4c5d46038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00007fd4c5135f80 RCX: 00007fd4c4f7cef9
RDX: 0000000020000180 RSI: 0000000020000140 RDI: 0000000020000100
RBP: 00007fd4c4fef01e R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000027 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd4c5135f80 R15: 00007fffe9f7afe8
 </TASK>


---
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