============================================
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
syz.0.61/6370 is trying to acquire lock:
ffff8880401aa0a0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x18d/0x300 fs/hfs/bfind.c:-1
but task is already holding lock:
ffff8880401aa0a0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x18d/0x300 fs/hfs/bfind.c:-1
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&tree->tree_lock#2/1);
lock(&tree->tree_lock#2/1);
*** DEADLOCK ***
May be due to missing lock nesting notation
locks held by syz.0.61/6370: 5, last CPU#1:
#0: ffff88804020c528 (sb_writers#17){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:531
#1: ffff8880289d15f0 (&sb->s_type->i_mutex_key#34){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1031 [inline]
#1: ffff8880289d15f0 (&sb->s_type->i_mutex_key#34){+.+.}-{4:4}, at: do_truncate+0x18f/0x250 fs/open.c:63
#2: ffff8880289d1418 (&HFS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xf9/0x1680 fs/hfs/extent.c:403
#3: ffff8880401aa0a0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x18d/0x300 fs/hfs/bfind.c:-1
#4: ffff8880289d2798 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xf9/0x1680 fs/hfs/extent.c:403
stack backtrace:
CPU: 1 UID: 0 PID: 6370 Comm: syz.0.61 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_deadlock_bug+0x27a/0x290 kernel/locking/lockdep.c:3085
check_deadlock kernel/locking/lockdep.c:3137 [inline]
validate_chain kernel/locking/lockdep.c:3939 [inline]
__lock_acquire+0x25db/0x2de0 kernel/locking/lockdep.c:5288
lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
__mutex_lock_common kernel/locking/rtmutex_api.c:561 [inline]
mutex_lock_nested+0x55/0x1d0 kernel/locking/rtmutex_api.c:580
hfs_find_init+0x18d/0x300 fs/hfs/bfind.c:-1
hfs_ext_read_extent fs/hfs/extent.c:206 [inline]
hfs_extend_file+0x367/0x1680 fs/hfs/extent.c:407
hfs_bmap_reserve+0x108/0x430 fs/hfs/btree.c:402
__hfs_ext_write_extent+0x200/0x620 fs/hfs/extent.c:121
__hfs_ext_cache_extent+0x6e/0x9b0 fs/hfs/extent.c:180
hfs_ext_read_extent fs/hfs/extent.c:208 [inline]
hfs_extend_file+0x3ad/0x1680 fs/hfs/extent.c:407
hfs_get_block+0x401/0xbf0 fs/hfs/extent.c:359
__block_write_begin_int+0x6c1/0x1930 fs/buffer.c:2031
block_write_begin fs/buffer.c:2145 [inline]
cont_write_begin+0x71b/0xac0 fs/buffer.c:2507
hfs_write_begin+0x123/0x1c0 fs/hfs/inode.c:62
cont_expand_zero fs/buffer.c:2435 [inline]
cont_write_begin+0x2d6/0xac0 fs/buffer.c:2497
hfs_write_begin+0x123/0x1c0 fs/hfs/inode.c:62
hfs_file_truncate+0x1d2/0xb70 fs/hfs/extent.c:501
hfs_inode_setattr+0x4d0/0x730 fs/hfs/inode.c:688
notify_change+0xbb8/0xec0 fs/attr.c:556
do_truncate+0x1c2/0x250 fs/open.c:68
vfs_truncate+0x4ba/0x540 fs/open.c:118
ksys_truncate+0xf3/0x1c0 fs/open.c:142
__do_sys_truncate fs/open.c:154 [inline]
__se_sys_truncate fs/open.c:152 [inline]
__x64_sys_truncate+0x5b/0x70 fs/open.c:152
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fefdbb1fb19
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fefd18f2028 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 00007fefdbda6360 RCX: 00007fefdbb1fb19
RDX: 0000000000000000 RSI: 00000000007fffff RDI: 0000200000000940
RBP: 00007fefdbbb7b70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fefdbda63f8 R14: 00007fefdbda6360 R15: 00007ffc5c1a2478
------------[ cut here ]------------
rtmutex deadlock detected
WARNING: kernel/locking/rtmutex.c:1698 at rt_mutex_handle_deadlock+0x21/0xb0 kernel/locking/rtmutex.c:1698, CPU#0: syz.0.61/6370
Modules linked in:
CPU: 0 UID: 0 PID: 6370 Comm: syz.0.61 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026
RIP: 0010:rt_mutex_handle_deadlock+0x21/0xb0 kernel/locking/rtmutex.c:1698
Code: 90 90 90 90 90 90 90 90 90 41 57 41 56 41 55 41 54 53 83 ff dd 0f 85 81 00 00 00 48 89 f7 e8 76 42 01 00 48 8d 3d ef b6 60 05 <67> 48 0f b9 3a 4c 8d 3d 00 00 00 00 65 48 8b 1d f3 07 59 08 4c 8d
RSP: 0018:ffffc90007c3ebd0 EFLAGS: 00010286
RAX: 8000000000000000 RBX: 00000000ffffffdd RCX: ffffffff9ada6a01
RDX: 0000000000000001 RSI: ffffffff8bed2f60 RDI: ffffffff90d8bef0
RBP: ffffc90007c3ed68 R08: ffffffff90d5a7bf R09: 1ffffffff21ab4f7
R10: dffffc0000000000 R11: fffffbfff21ab4f8 R12: 1ffff92000f87d88
R13: ffffffff8b780242 R14: ffff8880401aa048 R15: dffffc0000000000
FS: 00007fefd18f26c0(0000) GS:ffff88812470f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555908ff4e8 CR3: 0000000026d34000 CR4: 00000000003526f0
Call Trace:
__rt_mutex_slowlock kernel/locking/rtmutex.c:1760 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1787 [inline]
rt_mutex_slowlock+0x73e/0x780 kernel/locking/rtmutex.c:1827
__rt_mutex_lock kernel/locking/rtmutex.c:1842 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:562 [inline]
mutex_lock_nested+0x163/0x1d0 kernel/locking/rtmutex_api.c:580
hfs_find_init+0x18d/0x300 fs/hfs/bfind.c:-1
hfs_ext_read_extent fs/hfs/extent.c:206 [inline]
hfs_extend_file+0x367/0x1680 fs/hfs/extent.c:407
hfs_bmap_reserve+0x108/0x430 fs/hfs/btree.c:402
__hfs_ext_write_extent+0x200/0x620 fs/hfs/extent.c:121
__hfs_ext_cache_extent+0x6e/0x9b0 fs/hfs/extent.c:180
hfs_ext_read_extent fs/hfs/extent.c:208 [inline]
hfs_extend_file+0x3ad/0x1680 fs/hfs/extent.c:407
hfs_get_block+0x401/0xbf0 fs/hfs/extent.c:359
__block_write_begin_int+0x6c1/0x1930 fs/buffer.c:2031
block_write_begin fs/buffer.c:2145 [inline]
cont_write_begin+0x71b/0xac0 fs/buffer.c:2507
hfs_write_begin+0x123/0x1c0 fs/hfs/inode.c:62
cont_expand_zero fs/buffer.c:2435 [inline]
cont_write_begin+0x2d6/0xac0 fs/buffer.c:2497
hfs_write_begin+0x123/0x1c0 fs/hfs/inode.c:62
hfs_file_truncate+0x1d2/0xb70 fs/hfs/extent.c:501
hfs_inode_setattr+0x4d0/0x730 fs/hfs/inode.c:688
notify_change+0xbb8/0xec0 fs/attr.c:556
do_truncate+0x1c2/0x250 fs/open.c:68
vfs_truncate+0x4ba/0x540 fs/open.c:118
ksys_truncate+0xf3/0x1c0 fs/open.c:142
__do_sys_truncate fs/open.c:154 [inline]
__se_sys_truncate fs/open.c:152 [inline]
__x64_sys_truncate+0x5b/0x70 fs/open.c:152
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fefdbb1fb19
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fefd18f2028 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 00007fefdbda6360 RCX: 00007fefdbb1fb19
RDX: 0000000000000000 RSI: 00000000007fffff RDI: 0000200000000940
RBP: 00007fefdbbb7b70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fefdbda63f8 R14: 00007fefdbda6360 R15: 00007ffc5c1a2478
----------------
Code disassembly (best guess):
0: 90 nop
1: 90 nop
2: 90 nop
3: 90 nop
4: 90 nop
5: 90 nop
6: 90 nop
7: 90 nop
8: 90 nop
9: 41 57 push %r15
b: 41 56 push %r14
d: 41 55 push %r13
f: 41 54 push %r12
11: 53 push %rbx
12: 83 ff dd cmp $0xffffffdd,%edi
15: 0f 85 81 00 00 00 jne 0x9c
1b: 48 89 f7 mov %rsi,%rdi
1e: e8 76 42 01 00 call 0x14299
23: 48 8d 3d ef b6 60 05 lea 0x560b6ef(%rip),%rdi # 0x560b719
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: 4c 8d 3d 00 00 00 00 lea 0x0(%rip),%r15 # 0x36
36: 65 48 8b 1d f3 07 59 mov %gs:0x85907f3(%rip),%rbx # 0x8590831
3d: 08
3e: 4c rex.WR
3f: 8d .byte 0x8d