Message-ID: <000000000000ae358c06202ca726@google.com>
Date: Wed, 21 Aug 2024 00:40:24 -0700
From: syzbot <syzbot+d78497256d53041ee229@...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_setattr

Hello,

syzbot found the following issue on:

HEAD commit:    521b1e7f4cf0 Merge tag 'cxl-fixes-6.11-rc5' of git://git.k..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=175453cb980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=df2f0ed7e30a639d
dashboard link: https://syzkaller.appspot.com/bug?extid=d78497256d53041ee229
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1395e991980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=13659d6b980000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-521b1e7f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fc256e887f7f/vmlinux-521b1e7f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0ecca3914e31/bzImage-521b1e7f.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/4ad0fdc1f43e/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d78497256d53041ee229@...kaller.appspotmail.com

JBD2: Ignoring recovery information on journal
ocfs2: Mounting device (7,0) on (node local, slot 0) with writeback data mode.
======================================================
WARNING: possible circular locking dependency detected
6.11.0-rc4-syzkaller-00011-g521b1e7f4cf0 #0 Not tainted
------------------------------------------------------
syz-executor408/5110 is trying to acquire lock:
ffff888037bf6610 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_setattr+0xcb1/0x1f50 fs/ocfs2/file.c:1259

but task is already holding lock:
ffff88803c2bcda0 (&oi->ip_alloc_sem){+.+.}-{3:3}, at: ocfs2_setattr+0xc9f/0x1f50 fs/ocfs2/file.c:1258

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&oi->ip_alloc_sem){+.+.}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       down_write+0x99/0x220 kernel/locking/rwsem.c:1579
       ocfs2_try_remove_refcount_tree+0xb6/0x330 fs/ocfs2/refcounttree.c:931
       ocfs2_xattr_set+0xa4f/0x1930 fs/ocfs2/xattr.c:3670
       ocfs2_set_acl+0x4cb/0x580 fs/ocfs2/acl.c:254
       ocfs2_iop_set_acl+0x24a/0x3c0 fs/ocfs2/acl.c:286
       set_posix_acl fs/posix_acl.c:955 [inline]
       vfs_set_acl+0x7fd/0xa60 fs/posix_acl.c:1134
       do_setxattr fs/xattr.c:626 [inline]
       path_setxattr+0x3bd/0x4d0 fs/xattr.c:658
       __do_sys_setxattr fs/xattr.c:676 [inline]
       __se_sys_setxattr fs/xattr.c:672 [inline]
       __x64_sys_setxattr+0xbb/0xd0 fs/xattr.c:672
       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 (&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
       vfs_create+0x23c/0x3d0 fs/namei.c:3280
       do_mknodat+0x447/0x5b0 fs/namei.c:4138
       __do_sys_mknodat fs/namei.c:4166 [inline]
       __se_sys_mknodat fs/namei.c:4163 [inline]
       __x64_sys_mknodat+0xa7/0xc0 fs/namei.c:4163
       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 (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
       vfs_create+0x23c/0x3d0 fs/namei.c:3280
       do_mknodat+0x447/0x5b0 fs/namei.c:4138
       __do_sys_mknodat fs/namei.c:4166 [inline]
       __se_sys_mknodat fs/namei.c:4163 [inline]
       __x64_sys_mknodat+0xa7/0xc0 fs/namei.c:4163
       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 (&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
       vfs_create+0x23c/0x3d0 fs/namei.c:3280
       do_mknodat+0x447/0x5b0 fs/namei.c:4138
       __do_sys_mknodat fs/namei.c:4166 [inline]
       __se_sys_mknodat fs/namei.c:4163 [inline]
       __x64_sys_mknodat+0xa7/0xc0 fs/namei.c:4163
       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 (sb_internal#2){.+.+}-{0:0}:
       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
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1675 [inline]
       sb_start_intwrite include/linux/fs.h:1858 [inline]
       ocfs2_start_trans+0x2b9/0x700 fs/ocfs2/journal.c:348
       ocfs2_setattr+0xcb1/0x1f50 fs/ocfs2/file.c:1259
       notify_change+0xb9d/0xe70 fs/attr.c:495
       chmod_common+0x2ab/0x4c0 fs/open.c:654
       do_fchmodat fs/open.c:702 [inline]
       __do_sys_fchmodat fs/open.c:721 [inline]
       __se_sys_fchmodat fs/open.c:718 [inline]
       __x64_sys_fchmodat+0x11d/0x1c0 fs/open.c:718
       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:
  sb_internal#2 --> &oi->ip_xattr_sem --> &oi->ip_alloc_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&oi->ip_alloc_sem);
                               lock(&oi->ip_xattr_sem);
                               lock(&oi->ip_alloc_sem);
  rlock(sb_internal#2);

 *** DEADLOCK ***

3 locks held by syz-executor408/5110:
 #0: ffff888037bf6420 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
 #1: ffff88803c2bd100 (&sb->s_type->i_mutex_key#15){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:799 [inline]
 #1: ffff88803c2bd100 (&sb->s_type->i_mutex_key#15){+.+.}-{3:3}, at: chmod_common+0x1bb/0x4c0 fs/open.c:648
 #2: ffff88803c2bcda0 (&oi->ip_alloc_sem){+.+.}-{3:3}, at: ocfs2_setattr+0xc9f/0x1f50 fs/ocfs2/file.c:1258

stack backtrace:
CPU: 0 UID: 0 PID: 5110 Comm: syz-executor408 Not tainted 6.11.0-rc4-syzkaller-00011-g521b1e7f4cf0 #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
 percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
 __sb_start_write include/linux/fs.h:1675 [inline]
 sb_start_intwrite include/linux/fs.h:1858 [inline]
 ocfs2_start_trans+0x2b9/0x700 fs/ocfs2/journal.c:348
 ocfs2_setattr+0xcb1/0x1f50 fs/ocfs2/file.c:1259
 notify_change+0xb9d/0xe70 fs/attr.c:495
 chmod_common+0x2ab/0x4c0 fs/open.c:654
 do_fchmodat fs/open.c:702 [inline]
 __do_sys_fchmodat fs/open.c:721 [inline]
 __se_sys_fchmodat fs/open.c:718 [inline]
 __x64_sys_fchmodat+0x11d/0x1c0 fs/open.c:718
 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: 0033:0x7ff865822659
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffa6552a68 EFLAGS: 00000246 ORIG_RAX: 000000000000010c
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff865822659
RDX: 00000000000001ff RSI: 0000000020000440 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007fffa6552aa0
R10: 00007fffa6552a70 R11: 0000000000000246 R12: 00007fffa6552aa0
R13: 00007fffa6552d28 R14: 431bde82d7b634db R15: 00007ff86586b03b
 </TASK>


---
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