syzbot

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.0.17/4514 is trying to acquire lock:
ffff0000e9a90980 (&type->i_mutex_dir_key#8/3){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline]
ffff0000e9a90980 (&type->i_mutex_dir_key#8/3){+.+.}-{3:3}, at: open_xa_root fs/reiserfs/xattr.c:127 [inline]
ffff0000e9a90980 (&type->i_mutex_dir_key#8/3){+.+.}-{3:3}, at: open_xa_dir+0x118/0x5d4 fs/reiserfs/xattr.c:152

but task is already holding lock:
ffff0000d355d090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x68/0xd8 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+0x190/0x1f38 kernel/locking/mutex.c:603
       __mutex_lock kernel/locking/mutex.c:747 [inline]
       mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
       reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
       reiserfs_mkdir+0x278/0x788 fs/reiserfs/namei.c:831
       xattr_mkdir fs/reiserfs/xattr.c:76 [inline]
       open_xa_root fs/reiserfs/xattr.c:136 [inline]
       open_xa_dir+0x284/0x5d4 fs/reiserfs/xattr.c:152
       xattr_lookup+0x3c/0x268 fs/reiserfs/xattr.c:395
       reiserfs_xattr_set_handle+0xd8/0xd94 fs/reiserfs/xattr.c:533
       __reiserfs_set_acl+0x428/0x5b0 fs/reiserfs/xattr_acl.c:276
       reiserfs_set_acl+0x3ac/0x540 fs/reiserfs/xattr_acl.c:50
       set_posix_acl fs/posix_acl.c:1160 [inline]
       posix_acl_xattr_set+0x2f8/0x398 fs/posix_acl.c:1189
       __vfs_setxattr+0x388/0x3a4 fs/xattr.c:182
       __vfs_setxattr_noperm+0x120/0x564 fs/xattr.c:216
       __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:277
       vfs_setxattr+0x158/0x2ac fs/xattr.c:309
       do_setxattr fs/xattr.c:594 [inline]
       setxattr+0x228/0x28c fs/xattr.c:617
       path_setxattr+0x12c/0x25c fs/xattr.c:636
       __do_sys_setxattr fs/xattr.c:652 [inline]
       __se_sys_setxattr fs/xattr.c:648 [inline]
       __arm64_sys_setxattr+0xbc/0xd8 fs/xattr.c:648
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
       do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
       el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

-> #0 (&type->i_mutex_dir_key#8/3){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3090 [inline]
       check_prevs_add kernel/locking/lockdep.c:3209 [inline]
       validate_chain kernel/locking/lockdep.c:3825 [inline]
       __lock_acquire+0x293c/0x6544 kernel/locking/lockdep.c:5049
       lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662
       down_write_nested+0x64/0x94 kernel/locking/rwsem.c:1689
       inode_lock_nested include/linux/fs.h:793 [inline]
       open_xa_root fs/reiserfs/xattr.c:127 [inline]
       open_xa_dir+0x118/0x5d4 fs/reiserfs/xattr.c:152
       reiserfs_for_each_xattr+0x16c/0x68c fs/reiserfs/xattr.c:252
       reiserfs_delete_xattrs+0x2c/0xa4 fs/reiserfs/xattr.c:364
       reiserfs_evict_inode+0x1e0/0x3e4 fs/reiserfs/inode.c:53
       evict+0x3c8/0x810 fs/inode.c:705
       iput_final fs/inode.c:1834 [inline]
       iput+0x764/0x7f4 fs/inode.c:1860
       reiserfs_new_inode+0xa98/0x133c fs/reiserfs/inode.c:2156
       reiserfs_create+0x334/0x5a8 fs/reiserfs/namei.c:668
       lookup_open fs/namei.c:3490 [inline]
       open_last_lookups fs/namei.c:3558 [inline]
       path_openat+0x112c/0x2680 fs/namei.c:3788
       do_filp_open+0x174/0x344 fs/namei.c:3818
       do_sys_openat2+0x128/0x3d8 fs/open.c:1320
       do_sys_open fs/open.c:1336 [inline]
       __do_sys_openat fs/open.c:1352 [inline]
       __se_sys_openat fs/open.c:1347 [inline]
       __arm64_sys_openat+0x120/0x154 fs/open.c:1347
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
       do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
       el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

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.0.17/4514:
 #0: ffff0000d583a460 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:402
 #1: ffff0000e9a91020 (&type->i_mutex_dir_key#8){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff0000e9a91020 (&type->i_mutex_dir_key#8){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3555 [inline]
 #1: ffff0000e9a91020 (&type->i_mutex_dir_key#8){+.+.}-{3:3}, at: path_openat+0x5e4/0x2680 fs/namei.c:3788
 #2: ffff0000d355d090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x68/0xd8 fs/reiserfs/lock.c:78

stack backtrace:
CPU: 1 PID: 4514 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106
 dump_stack+0x1c/0x5c lib/dump_stack.c:113
 print_circular_bug+0x148/0x1b0 kernel/locking/lockdep.c:2048
 check_noncircular+0x240/0x2d4 kernel/locking/lockdep.c:2170
 check_prev_add kernel/locking/lockdep.c:3090 [inline]
 check_prevs_add kernel/locking/lockdep.c:3209 [inline]
 validate_chain kernel/locking/lockdep.c:3825 [inline]
 __lock_acquire+0x293c/0x6544 kernel/locking/lockdep.c:5049
 lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662
 down_write_nested+0x64/0x94 kernel/locking/rwsem.c:1689
 inode_lock_nested include/linux/fs.h:793 [inline]
 open_xa_root fs/reiserfs/xattr.c:127 [inline]
 open_xa_dir+0x118/0x5d4 fs/reiserfs/xattr.c:152
 reiserfs_for_each_xattr+0x16c/0x68c fs/reiserfs/xattr.c:252
 reiserfs_delete_xattrs+0x2c/0xa4 fs/reiserfs/xattr.c:364
 reiserfs_evict_inode+0x1e0/0x3e4 fs/reiserfs/inode.c:53
 evict+0x3c8/0x810 fs/inode.c:705
 iput_final fs/inode.c:1834 [inline]
 iput+0x764/0x7f4 fs/inode.c:1860
 reiserfs_new_inode+0xa98/0x133c fs/reiserfs/inode.c:2156
 reiserfs_create+0x334/0x5a8 fs/reiserfs/namei.c:668
 lookup_open fs/namei.c:3490 [inline]
 open_last_lookups fs/namei.c:3558 [inline]
 path_openat+0x112c/0x2680 fs/namei.c:3788
 do_filp_open+0x174/0x344 fs/namei.c:3818
 do_sys_openat2+0x128/0x3d8 fs/open.c:1320
 do_sys_open fs/open.c:1336 [inline]
 __do_sys_openat fs/open.c:1352 [inline]
 __se_sys_openat fs/open.c:1347 [inline]
 __arm64_sys_openat+0x120/0x154 fs/open.c:1347
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585