============================================
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
syz.1.29/6139 is trying to acquire lock:
ffff8880655b60a0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1
but task is already holding lock:
ffff8880655b60a0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&tree->tree_lock/1);
lock(&tree->tree_lock/1);
*** DEADLOCK ***
May be due to missing lock nesting notation
5 locks held by syz.1.29/6139:
#0: ffff888032808480 (sb_writers#23){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2710 [inline]
#0: ffff888032808480 (sb_writers#23){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:684
#1: ffff88806052bd00 (&sb->s_type->i_mutex_key#33){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#1: ffff88806052bd00 (&sb->s_type->i_mutex_key#33){+.+.}-{4:4}, at: generic_file_write_iter+0x11f/0x690 mm/filemap.c:4459
#2: ffff88806052bb28 (&HFS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xf2/0x15e0 fs/hfs/extent.c:397
#3: ffff8880655b60a0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1
#4: ffff88806052d0e8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xf2/0x15e0 fs/hfs/extent.c:397
stack backtrace:
CPU: 0 UID: 0 PID: 6139 Comm: syz.1.29 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_deadlock_bug+0x279/0x290 kernel/locking/lockdep.c:3041
check_deadlock kernel/locking/lockdep.c:3093 [inline]
validate_chain kernel/locking/lockdep.c:3895 [inline]
__lock_acquire+0x253f/0x2cf0 kernel/locking/lockdep.c:5237
lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868
__mutex_lock_common kernel/locking/rtmutex_api.c:533 [inline]
mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:552
hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1
hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
hfs_extend_file+0x35c/0x15e0 fs/hfs/extent.c:401
hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269
__hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121
__hfs_ext_cache_extent+0x6b/0x9b0 fs/hfs/extent.c:174
hfs_ext_read_extent fs/hfs/extent.c:202 [inline]
hfs_extend_file+0x39b/0x15e0 fs/hfs/extent.c:401
hfs_get_block+0x412/0xc50 fs/hfs/extent.c:353
__block_write_begin_int+0x6c6/0x1910 fs/buffer.c:2142
block_write_begin fs/buffer.c:2253 [inline]
cont_write_begin+0x737/0xae0 fs/buffer.c:2591
hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:53
cont_expand_zero fs/buffer.c:2519 [inline]
cont_write_begin+0x2e7/0xae0 fs/buffer.c:2581
hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:53
generic_perform_write+0x2af/0x8b0 mm/filemap.c:4319
generic_file_write_iter+0x14b/0x690 mm/filemap.c:4462
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x629/0xba0 fs/read_write.c:688
ksys_pwrite64 fs/read_write.c:795 [inline]
__do_sys_pwrite64 fs/read_write.c:803 [inline]
__se_sys_pwrite64 fs/read_write.c:800 [inline]
__x64_sys_pwrite64+0x19c/0x230 fs/read_write.c:800
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb6476fc799
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:00007fb64594e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 00007fb647975fa0 RCX: 00007fb6476fc799
RDX: 0000000000000001 RSI: 0000200000000140 RDI: 0000000000000004
RBP: 00007fb647792c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000008080c61 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb647976038 R14: 00007fb647975fa0 R15: 00007ffd6285cfb8
------------[ cut here ]------------
rtmutex deadlock detected
WARNING: kernel/locking/rtmutex.c:1674 at rt_mutex_handle_deadlock+0x21/0xb0 kernel/locking/rtmutex.c:1674, CPU#0: syz.1.29/6139
Modules linked in:
CPU: 0 UID: 0 PID: 6139 Comm: syz.1.29 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:rt_mutex_handle_deadlock+0x21/0xb0 kernel/locking/rtmutex.c:1674
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 56 3a 01 00 48 8d 3d bf f0 47 04 <67> 48 0f b9 3a 4c 8d 3d 00 00 00 00 65 48 8b 1d b3 c3 28 07 4c 8d
RSP: 0018:ffffc90005fbebd0 EFLAGS: 00010286
RAX: 0000000080000000 RBX: ffffc90005fbec60 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8ba671e0 RDI: ffffffff8f6d7d00
RBP: ffffc90005fbed68 R08: ffffffff8f6a4ab7 R09: 1ffffffff1ed4956
R10: dffffc0000000000 R11: fffffbfff1ed4957 R12: 1ffff92000bf7d88
R13: ffffffff8b25865d R14: ffff8880655b6048 R15: dffffc0000000000
FS: 00007fb64594e6c0(0000) GS:ffff88812633b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5643025000 CR3: 000000003366e000 CR4: 00000000003526f0
Call Trace:
__rt_mutex_slowlock kernel/locking/rtmutex.c:1734 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline]
rt_mutex_slowlock+0x760/0x7b0 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:534 [inline]
mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:552
hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1
hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
hfs_extend_file+0x35c/0x15e0 fs/hfs/extent.c:401
hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269
__hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121
__hfs_ext_cache_extent+0x6b/0x9b0 fs/hfs/extent.c:174
hfs_ext_read_extent fs/hfs/extent.c:202 [inline]
hfs_extend_file+0x39b/0x15e0 fs/hfs/extent.c:401
hfs_get_block+0x412/0xc50 fs/hfs/extent.c:353
__block_write_begin_int+0x6c6/0x1910 fs/buffer.c:2142
block_write_begin fs/buffer.c:2253 [inline]
cont_write_begin+0x737/0xae0 fs/buffer.c:2591
hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:53
cont_expand_zero fs/buffer.c:2519 [inline]
cont_write_begin+0x2e7/0xae0 fs/buffer.c:2581
hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:53
generic_perform_write+0x2af/0x8b0 mm/filemap.c:4319
generic_file_write_iter+0x14b/0x690 mm/filemap.c:4462
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x629/0xba0 fs/read_write.c:688
ksys_pwrite64 fs/read_write.c:795 [inline]
__do_sys_pwrite64 fs/read_write.c:803 [inline]
__se_sys_pwrite64 fs/read_write.c:800 [inline]
__x64_sys_pwrite64+0x19c/0x230 fs/read_write.c:800
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb6476fc799
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:00007fb64594e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 00007fb647975fa0 RCX: 00007fb6476fc799
RDX: 0000000000000001 RSI: 0000200000000140 RDI: 0000000000000004
RBP: 00007fb647792c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000008080c61 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb647976038 R14: 00007fb647975fa0 R15: 00007ffd6285cfb8
----------------
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 56 3a 01 00 call 0x13a79
23: 48 8d 3d bf f0 47 04 lea 0x447f0bf(%rip),%rdi # 0x447f0e9
* 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 b3 c3 28 mov %gs:0x728c3b3(%rip),%rbx # 0x728c3f1
3d: 07
3e: 4c rex.WR
3f: 8d .byte 0x8d