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REISERFS warning (device loop0): sh-2029: %s: bitmap block (#%u) reading failed reiserfs_read_bitmap_block: reiserfs_read_bitmap_block
REISERFS warning (device loop0): sh-2029: %s: bitmap block (#%u) reading failed reiserfs_read_bitmap_block: reiserfs_read_bitmap_block
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.17/5949 is trying to acquire lock:
ffff88805e8f0990 (&type->i_mutex_dir_key#8/3){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:839 [inline]
ffff88805e8f0990 (&type->i_mutex_dir_key#8/3){+.+.}-{3:3}, at: open_xa_root fs/reiserfs/xattr.c:128 [inline]
ffff88805e8f0990 (&type->i_mutex_dir_key#8/3){+.+.}-{3:3}, at: open_xa_dir+0x122/0x6f0 fs/reiserfs/xattr.c:153

but task is already holding lock:
ffff88807ac73090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x60/0xd0 fs/reiserfs/lock.c:78

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&sbi->lock){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747
       reiserfs_write_lock+0x79/0xd0 fs/reiserfs/lock.c:27
       reiserfs_mkdir+0x310/0x970 fs/reiserfs/namei.c:829
       xattr_mkdir fs/reiserfs/xattr.c:77 [inline]
       open_xa_root fs/reiserfs/xattr.c:137 [inline]
       open_xa_dir+0x31a/0x6f0 fs/reiserfs/xattr.c:153
       xattr_lookup+0x22/0x2a0 fs/reiserfs/xattr.c:396
       reiserfs_xattr_set_handle+0xf9/0xd40 fs/reiserfs/xattr.c:535
       __reiserfs_set_acl+0x51e/0x640 fs/reiserfs/xattr_acl.c:277
       reiserfs_set_acl+0x45a/0x600 fs/reiserfs/xattr_acl.c:51
       set_posix_acl fs/posix_acl.c:956 [inline]
       vfs_set_acl+0x803/0xa60 fs/posix_acl.c:1135
       do_set_acl+0xf5/0x180 fs/posix_acl.c:1280
       do_setxattr fs/xattr.c:627 [inline]
       __do_sys_fsetxattr fs/xattr.c:711 [inline]
       __se_sys_fsetxattr+0x450/0x4b0 fs/xattr.c:687
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&type->i_mutex_dir_key#8/3){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain kernel/locking/lockdep.c:3869 [inline]
       __lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
       lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
       down_write_nested+0x9e/0x1f0 kernel/locking/rwsem.c:1689
       inode_lock_nested include/linux/fs.h:839 [inline]
       open_xa_root fs/reiserfs/xattr.c:128 [inline]
       open_xa_dir+0x122/0x6f0 fs/reiserfs/xattr.c:153
       reiserfs_for_each_xattr+0x17b/0x960 fs/reiserfs/xattr.c:253
       reiserfs_delete_xattrs+0x20/0x90 fs/reiserfs/xattr.c:365
       reiserfs_evict_inode+0x225/0x490 fs/reiserfs/inode.c:53
       evict+0x486/0x870 fs/inode.c:705
       reiserfs_new_inode+0x5cc/0x17d0 fs/reiserfs/inode.c:2152
       reiserfs_mknod+0x3ee/0x6c0 fs/reiserfs/namei.c:746
       vfs_mknod+0x32b/0x360 fs/namei.c:3991
       do_mknodat+0x37e/0x4f0 fs/namei.c:-1
       __do_sys_mknodat fs/namei.c:4069 [inline]
       __se_sys_mknodat fs/namei.c:4066 [inline]
       __x64_sys_mknodat+0xa9/0xc0 fs/namei.c:4066
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sbi->lock);
                               lock(&type->i_mutex_dir_key#8/3);
                               lock(&sbi->lock);
  lock(&type->i_mutex_dir_key#8/3);

 *** DEADLOCK ***

3 locks held by syz.0.17/5949:
 #0: ffff888028aee418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:403
 #1: ffff88805e8f02f0 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:839 [inline]
 #1: ffff88805e8f02f0 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: filename_create+0x1f6/0x460 fs/namei.c:3882
 #2: ffff88807ac73090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x60/0xd0 fs/reiserfs/lock.c:78

stack backtrace:
CPU: 1 PID: 5949 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
 check_noncircular+0x2bd/0x3c0 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain kernel/locking/lockdep.c:3869 [inline]
 __lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
 down_write_nested+0x9e/0x1f0 kernel/locking/rwsem.c:1689
 inode_lock_nested include/linux/fs.h:839 [inline]
 open_xa_root fs/reiserfs/xattr.c:128 [inline]
 open_xa_dir+0x122/0x6f0 fs/reiserfs/xattr.c:153
 reiserfs_for_each_xattr+0x17b/0x960 fs/reiserfs/xattr.c:253
 reiserfs_delete_xattrs+0x20/0x90 fs/reiserfs/xattr.c:365
 reiserfs_evict_inode+0x225/0x490 fs/reiserfs/inode.c:53
 evict+0x486/0x870 fs/inode.c:705
 reiserfs_new_inode+0x5cc/0x17d0 fs/reiserfs/inode.c:2152
 reiserfs_mknod+0x3ee/0x6c0 fs/reiserfs/namei.c:746
 vfs_mknod+0x32b/0x360 fs/namei.c:3991
 do_mknodat+0x37e/0x4f0 fs/namei.c:-1
 __do_sys_mknodat fs/namei.c:4069 [inline]
 __se_sys_mknodat fs/namei.c:4066 [inline]
 __x64_sys_mknodat+0xa9/0xc0 fs/namei.c:4066
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f272a18eba9
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:00007ffe72291bc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000103
RAX: ffffffffffffffda RBX: 00007f272a3d5fa0 RCX: 00007f272a18eba9
RDX: b0a54e68b1cd2fdb RSI: 0000200000000040 RDI: ffffffffffffff9c
RBP: 00007f272a211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000103 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f272a3d5fa0 R14: 00007f272a3d5fa0 R15: 0000000000000004
 </TASK>