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Date: Thu, 18 Apr 2024 07:41:20 -0700
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Subject: [syzbot] [hfs?] possible deadlock in hfs_extend_file (3)
From: syzbot <syzbot+2a62f58f1a4951a549bb@syzkaller.appspotmail.com>
To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, 
	syzkaller-bugs@googlegroups.com
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Hello,

syzbot found the following issue on:

HEAD commit:    fe46a7dd189e Merge tag 'sound-6.9-rc1' of git://git.kernel..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1556f7cb180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=aef2a55903e5791c
dashboard link: https://syzkaller.appspot.com/bug?extid=2a62f58f1a4951a549bb
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/089e25869df5/disk-fe46a7dd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/423b1787914f/vmlinux-fe46a7dd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4c043e30c07d/bzImage-fe46a7dd.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2a62f58f1a4951a549bb@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
6.8.0-syzkaller-08951-gfe46a7dd189e #0 Not tainted
------------------------------------------------------
syz-executor.3/5818 is trying to acquire lock:
ffff888060dd1af8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xa2/0xb10 fs/hfs/extent.c:397

but task is already holding lock:
ffff88802c4140b0 (&tree->tree_lock#2/1){+.+.}-{3:3}, at: hfs_find_init+0x183/0x220 fs/hfs/bfind.c:33

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&tree->tree_lock#2/1){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
       hfs_find_init+0x183/0x220 fs/hfs/bfind.c:33
       hfs_ext_read_extent+0x19c/0x9e0 fs/hfs/extent.c:200
       hfs_extend_file+0x4e4/0xb10 fs/hfs/extent.c:401
       hfs_bmap_reserve+0x29c/0x380 fs/hfs/btree.c:234
       hfs_cat_create+0x22b/0x810 fs/hfs/catalog.c:104
       hfs_create+0x6b/0xf0 fs/hfs/dir.c:202
       lookup_open.isra.0+0x10a1/0x13c0 fs/namei.c:3497
       open_last_lookups fs/namei.c:3566 [inline]
       path_openat+0x92f/0x2990 fs/namei.c:3796
       do_filp_open+0x1dc/0x430 fs/namei.c:3826
       do_sys_openat2+0x17a/0x1e0 fs/open.c:1406
       do_sys_open fs/open.c:1421 [inline]
       __do_sys_openat fs/open.c:1437 [inline]
       __se_sys_openat fs/open.c:1432 [inline]
       __x64_sys_openat+0x175/0x210 fs/open.c:1432
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x6d/0x75

-> #0 (&HFS_I(tree->inode)->extents_lock){+.+.}-{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+0x2478/0x3b30 kernel/locking/lockdep.c:5137
       lock_acquire kernel/locking/lockdep.c:5754 [inline]
       lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
       hfs_extend_file+0xa2/0xb10 fs/hfs/extent.c:397
       hfs_bmap_reserve+0x29c/0x380 fs/hfs/btree.c:234
       __hfs_ext_write_extent+0x3cf/0x520 fs/hfs/extent.c:121
       __hfs_ext_cache_extent fs/hfs/extent.c:174 [inline]
       hfs_ext_read_extent+0x809/0x9e0 fs/hfs/extent.c:202
       hfs_extend_file+0x4e4/0xb10 fs/hfs/extent.c:401
       hfs_get_block+0x17f/0x830 fs/hfs/extent.c:353
       __block_write_begin_int+0x4fb/0x16e0 fs/buffer.c:2105
       __block_write_begin fs/buffer.c:2154 [inline]
       block_write_begin+0xb1/0x4a0 fs/buffer.c:2213
       cont_write_begin+0x53d/0x740 fs/buffer.c:2567
       hfs_write_begin+0x87/0x150 fs/hfs/inode.c:53
       generic_perform_write+0x272/0x620 mm/filemap.c:3930
       __generic_file_write_iter+0x1fd/0x240 mm/filemap.c:4025
       generic_file_write_iter+0xe7/0x350 mm/filemap.c:4051
       call_write_iter include/linux/fs.h:2108 [inline]
       new_sync_write fs/read_write.c:497 [inline]
       vfs_write+0x6db/0x1100 fs/read_write.c:590
       ksys_write+0x12f/0x260 fs/read_write.c:643
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x6d/0x75

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.3/5818:
 #0: ffff888011652348 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xeb/0x180 fs/file.c:1191
 #1: ffff88802ce58420 (sb_writers#16){.+.+}-{0:0}, at: ksys_write+0x12f/0x260 fs/read_write.c:643
 #2: ffff888060dd6aa8 (&sb->s_type->i_mutex_key#23){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:793 [inline]
 #2: ffff888060dd6aa8 (&sb->s_type->i_mutex_key#23){+.+.}-{3:3}, at: generic_file_write_iter+0x92/0x350 mm/filemap.c:4048
 #3: ffff888060dd68f8 (&HFS_I(inode)->extents_lock#2){+.+.}-{3:3}, at: hfs_extend_file+0xa2/0xb10 fs/hfs/extent.c:397
 #4: ffff88802c4140b0 (&tree->tree_lock#2/1){+.+.}-{3:3}, at: hfs_find_init+0x183/0x220 fs/hfs/bfind.c:33

stack backtrace:
CPU: 0 PID: 5818 Comm: syz-executor.3 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 check_noncircular+0x31a/0x400 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+0x2478/0x3b30 kernel/locking/lockdep.c:5137
 lock_acquire kernel/locking/lockdep.c:5754 [inline]
 lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719
 __mutex_lock_common kernel/locking/mutex.c:608 [inline]
 __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
 hfs_extend_file+0xa2/0xb10 fs/hfs/extent.c:397
 hfs_bmap_reserve+0x29c/0x380 fs/hfs/btree.c:234
 __hfs_ext_write_extent+0x3cf/0x520 fs/hfs/extent.c:121
 __hfs_ext_cache_extent fs/hfs/extent.c:174 [inline]
 hfs_ext_read_extent+0x809/0x9e0 fs/hfs/extent.c:202
 hfs_extend_file+0x4e4/0xb10 fs/hfs/extent.c:401
 hfs_get_block+0x17f/0x830 fs/hfs/extent.c:353
 __block_write_begin_int+0x4fb/0x16e0 fs/buffer.c:2105
 __block_write_begin fs/buffer.c:2154 [inline]
 block_write_begin+0xb1/0x4a0 fs/buffer.c:2213
 cont_write_begin+0x53d/0x740 fs/buffer.c:2567
 hfs_write_begin+0x87/0x150 fs/hfs/inode.c:53
 generic_perform_write+0x272/0x620 mm/filemap.c:3930
 __generic_file_write_iter+0x1fd/0x240 mm/filemap.c:4025
 generic_file_write_iter+0xe7/0x350 mm/filemap.c:4051
 call_write_iter include/linux/fs.h:2108 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6db/0x1100 fs/read_write.c:590
 ksys_write+0x12f/0x260 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7efc4247de69
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007efc41fff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007efc425abf80 RCX: 00007efc4247de69
RDX: 000000000208e24b RSI: 00000000200004c0 RDI: 0000000000000005
RBP: 00007efc424ca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007efc425abf80 R15: 00007ffea65dcd48
 </TASK>


---
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