syzbot


possible deadlock in ocfs2_xattr_set

Status: upstream: reported on 2024/09/10 05:07
Subsystems: ocfs2
[Documentation on labels]
Reported-by: syzbot+ba9a789bd1f4d21fcefe@syzkaller.appspotmail.com
First crash: 11d, last: 4h45m
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [ocfs2?] possible deadlock in ocfs2_xattr_set 0 (1) 2024/09/10 05:07
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 possible deadlock in ocfs2_xattr_set 3 3d03h 3d19h 0/3 upstream: reported on 2024/09/14 01:11

Sample crash report:
ocfs2: Mounting device (7,2) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
6.11.0-syzkaller-04003-gfc1dc0d50780 #0 Not tainted
------------------------------------------------------
syz.2.1420/9523 is trying to acquire lock:
ffff8880583edf40 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline]
ffff8880583edf40 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}, at: ocfs2_xattr_set+0xe9e/0x1930 fs/ocfs2/xattr.c:3623

but task is already holding lock:
ffff88823bd366f8 (&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:

-> #2 (&oi->ip_xattr_sem){++++}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822
       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_mkdir+0x1ab/0x480 fs/ocfs2/namei.c:655
       vfs_mkdir+0x2fb/0x4f0 fs/namei.c:4257
       do_mkdirat+0x264/0x3a0 fs/namei.c:4280
       __do_sys_mkdir fs/namei.c:4300 [inline]
       __se_sys_mkdir fs/namei.c:4298 [inline]
       __x64_sys_mkdir+0x6c/0x80 fs/namei.c:4298
       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 (jbd2_handle){++++}-{0:0}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822
       jbd2_journal_lock_updates+0xaa/0x380 fs/jbd2/transaction.c:865
       __ocfs2_flush_truncate_log+0x2ea/0x1250 fs/ocfs2/alloc.c:6029
       ocfs2_flush_truncate_log+0x4f/0x70 fs/ocfs2/alloc.c:6076
       ocfs2_sync_fs+0x125/0x390 fs/ocfs2/super.c:402
       sync_filesystem+0x1ca/0x230 fs/sync.c:66
       ocfs2_remount+0x103/0xc30 fs/ocfs2/super.c:611
       reconfigure_super+0x447/0x880 fs/super.c:1083
       do_remount fs/namespace.c:3047 [inline]
       path_mount+0xc22/0xfa0 fs/namespace.c:3826
       do_mount fs/namespace.c:3847 [inline]
       __do_sys_mount fs/namespace.c:4055 [inline]
       __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4032
       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]#5){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3158 [inline]
       check_prevs_add kernel/locking/lockdep.c:3277 [inline]
       validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3901
       __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5199
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822
       down_write+0x99/0x220 kernel/locking/rwsem.c:1579
       inode_lock include/linux/fs.h:815 [inline]
       ocfs2_xattr_set+0xe9e/0x1930 fs/ocfs2/xattr.c:3623
       __vfs_setxattr+0x46a/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]#5 --> 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]#5);

 *** DEADLOCK ***

3 locks held by syz.2.1420/9523:
 #0: ffff88805ea3e420 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
 #1: ffff88823bd369c0 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline]
 #1: ffff88823bd369c0 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: vfs_setxattr+0x1e1/0x430 fs/xattr.c:320
 #2: ffff88823bd366f8 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_xattr_set+0x633/0x1930 fs/ocfs2/xattr.c:3584

stack backtrace:
CPU: 0 UID: 0 PID: 9523 Comm: syz.2.1420 Not tainted 6.11.0-syzkaller-04003-gfc1dc0d50780 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2203
 check_prev_add kernel/locking/lockdep.c:3158 [inline]
 check_prevs_add kernel/locking/lockdep.c:3277 [inline]
 validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3901
 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5199
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822
 down_write+0x99/0x220 kernel/locking/rwsem.c:1579
 inode_lock include/linux/fs.h:815 [inline]
 ocfs2_xattr_set+0xe9e/0x1930 fs/ocfs2/xattr.c:3623
 __vfs_setxattr+0x46a/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: 0033:0x7f23a457def9
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:00007f23a5420038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00007f23a4735f80 RCX: 00007f23a457def9
RDX: 0000000000000000 RSI: 00000000200002c0 RDI: 0000000020000280
RBP: 00007f23a45f0b76 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f23a4735f80 R15: 00007ffdbed78b58
 </TASK>

Crashes (15):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/17 16:22 upstream fc1dc0d50780 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in ocfs2_xattr_set
2024/09/17 16:22 upstream fc1dc0d50780 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in ocfs2_xattr_set
2024/09/17 16:09 upstream fc1dc0d50780 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in ocfs2_xattr_set
2024/09/17 16:07 upstream fc1dc0d50780 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in ocfs2_xattr_set
2024/09/17 16:01 upstream fc1dc0d50780 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in ocfs2_xattr_set
2024/09/17 16:01 upstream fc1dc0d50780 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in ocfs2_xattr_set
2024/09/16 05:25 upstream 98f7e32f20d2 08d8a733 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_set
2024/09/15 22:18 upstream d42f7708e27c 08d8a733 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_set
2024/09/15 02:01 upstream 0babf683783d 08d8a733 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_set
2024/09/14 04:30 upstream 196145c606d0 b58f933c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_set
2024/09/17 04:15 upstream a430d95c5efa c673ca06 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_xattr_set
2024/09/07 01:04 upstream b831f83e40a2 ce70880a .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_xattr_set
2024/09/06 04:58 upstream ad618736883b 464ac2ed .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_xattr_set
2024/09/06 04:58 upstream ad618736883b 464ac2ed .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_xattr_set
2024/09/14 04:38 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 5f5673607153 158f4851 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_xattr_set
* Struck through repros no longer work on HEAD.