syzbot

======================================================
WARNING: possible circular locking dependency detected
6.4.0-rc3-syzkaller-00004-g421ca22e3138 #0 Not tainted
------------------------------------------------------
syz-executor.0/9577 is trying to acquire lock:
ffff8880298dbb78 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xff/0x1440 fs/hfs/extent.c:397

but task is already holding lock:
ffff888037d0e0b0 (&tree->tree_lock#2/1){+.+.}-{3:3}, at: hfs_find_init+0x16e/0x1f0

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&tree->tree_lock#2/1){+.+.}-{3:3}:
       lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5691
       __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
       __mutex_lock kernel/locking/mutex.c:747 [inline]
       mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
       hfs_find_init+0x16e/0x1f0
       hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
       hfs_extend_file+0x31b/0x1440 fs/hfs/extent.c:401
       hfs_bmap_reserve+0xd9/0x3f0 fs/hfs/btree.c:234
       hfs_cat_create+0x1eb/0xa70 fs/hfs/catalog.c:104
       hfs_create+0x66/0xd0 fs/hfs/dir.c:202
       lookup_open fs/namei.c:3492 [inline]
       open_last_lookups fs/namei.c:3560 [inline]
       path_openat+0x13df/0x3170 fs/namei.c:3788
       do_filp_open+0x234/0x490 fs/namei.c:3818
       do_sys_openat2+0x13f/0x500 fs/open.c:1356
       do_sys_open fs/open.c:1372 [inline]
       __do_sys_openat fs/open.c:1388 [inline]
       __se_sys_openat fs/open.c:1383 [inline]
       __x64_sys_openat+0x247/0x290 fs/open.c:1383
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3108 [inline]
       check_prevs_add kernel/locking/lockdep.c:3227 [inline]
       validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3842
       __lock_acquire+0x1295/0x2000 kernel/locking/lockdep.c:5074
       lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5691
       __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
       __mutex_lock kernel/locking/mutex.c:747 [inline]
       mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
       hfs_extend_file+0xff/0x1440 fs/hfs/extent.c:397
       hfs_bmap_reserve+0xd9/0x3f0 fs/hfs/btree.c:234
       __hfs_ext_write_extent+0x22e/0x4f0 fs/hfs/extent.c:121
       __hfs_ext_cache_extent+0x6a/0x990 fs/hfs/extent.c:174
       hfs_ext_read_extent fs/hfs/extent.c:202 [inline]
       hfs_extend_file+0x344/0x1440 fs/hfs/extent.c:401
       hfs_get_block+0x3e4/0xb60 fs/hfs/extent.c:353
       __block_write_begin_int+0x548/0x1a50 fs/buffer.c:2064
       __block_write_begin fs/buffer.c:2114 [inline]
       block_write_begin+0x9c/0x1f0 fs/buffer.c:2175
       cont_write_begin+0x643/0x880 fs/buffer.c:2534
       hfs_write_begin+0x8a/0xd0 fs/hfs/inode.c:58
       generic_perform_write+0x300/0x5e0 mm/filemap.c:3923
       __generic_file_write_iter+0x17a/0x400 mm/filemap.c:4051
       generic_file_write_iter+0xaf/0x310 mm/filemap.c:4083
       call_write_iter include/linux/fs.h:1868 [inline]
       new_sync_write fs/read_write.c:491 [inline]
       vfs_write+0x790/0xb20 fs/read_write.c:584
       ksys_write+0x1a0/0x2c0 fs/read_write.c:637
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&tree->tree_lock#2/1);
                               lock(&HFS_I(tree->inode)->extents_lock);
                               lock(&tree->tree_lock#2/1);
  lock(&HFS_I(tree->inode)->extents_lock);

 *** DEADLOCK ***

5 locks held by syz-executor.0/9577:
 #0: ffff88802b46e0e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x254/0x2f0 fs/file.c:1047
 #1: 
ffff888077738460
 (sb_writers
#22){.+.+}-{0:0}
, at: vfs_write+0x223/0xb20 fs/read_write.c:580
 #2: ffff8880298dd0a8
 (&sb->s_type->i_mutex_key
#31){+.+.}-{3:3}
, at: inode_lock include/linux/fs.h:775 [inline]
, at: generic_file_write_iter+0x83/0x310 mm/filemap.c:4080
 #3: ffff8880298dcef8
 (&HFS_I(inode)->extents_lock
){+.+.}-{3:3}
, at: hfs_extend_file+0xff/0x1440 fs/hfs/extent.c:397
 #4: ffff888037d0e0b0
 (&tree->tree_lock
#2/1
){+.+.}-{3:3}
, at: hfs_find_init+0x16e/0x1f0

stack backtrace:
CPU: 1 PID: 9577 Comm: syz-executor.0 Not tainted 6.4.0-rc3-syzkaller-00004-g421ca22e3138 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x2fe/0x3b0 kernel/locking/lockdep.c:2188
 check_prev_add kernel/locking/lockdep.c:3108 [inline]
 check_prevs_add kernel/locking/lockdep.c:3227 [inline]
 validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3842
 __lock_acquire+0x1295/0x2000 kernel/locking/lockdep.c:5074
 lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5691
 __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
 hfs_extend_file+0xff/0x1440 fs/hfs/extent.c:397
 hfs_bmap_reserve+0xd9/0x3f0 fs/hfs/btree.c:234
 __hfs_ext_write_extent+0x22e/0x4f0 fs/hfs/extent.c:121
 __hfs_ext_cache_extent+0x6a/0x990 fs/hfs/extent.c:174
 hfs_ext_read_extent fs/hfs/extent.c:202 [inline]
 hfs_extend_file+0x344/0x1440 fs/hfs/extent.c:401
 hfs_get_block+0x3e4/0xb60 fs/hfs/extent.c:353
 __block_write_begin_int+0x548/0x1a50 fs/buffer.c:2064
 __block_write_begin fs/buffer.c:2114 [inline]
 block_write_begin+0x9c/0x1f0 fs/buffer.c:2175
 cont_write_begin+0x643/0x880 fs/buffer.c:2534
 hfs_write_begin+0x8a/0xd0 fs/hfs/inode.c:58
 generic_perform_write+0x300/0x5e0 mm/filemap.c:3923
 __generic_file_write_iter+0x17a/0x400 mm/filemap.c:4051
 generic_file_write_iter+0xaf/0x310 mm/filemap.c:4083
 call_write_iter include/linux/fs.h:1868 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x790/0xb20 fs/read_write.c:584
 ksys_write+0x1a0/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7faa1ec8c169
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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:00007faa1f902168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007faa1edabf80 RCX: 00007faa1ec8c169
RDX: 00000000000ffe00 RSI: 0000000020004200 RDI: 0000000000000004
RBP: 00007faa1ece7ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffcc3ac1bbf R14: 00007faa1f902300 R15: 0000000000022000
 </TASK>