loop0: detected capacity change from 0 to 64 ====================================================== WARNING: possible circular locking dependency detected 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0 Not tainted ------------------------------------------------------ syz.0.291/8425 is trying to acquire lock: ffff0000cdd460b0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x15c/0x1d8 fs/hfs/bfind.c:-1 but task is already holding lock: ffff0000cce300f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xd4/0xf4c fs/hfs/extent.c:397 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}: __mutex_lock_common+0x1d0/0x24ac kernel/locking/mutex.c:598 __mutex_lock kernel/locking/mutex.c:760 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:812 hfs_extend_file+0xd4/0xf4c fs/hfs/extent.c:397 hfs_bmap_reserve+0xd4/0x3e0 fs/hfs/btree.c:269 __hfs_ext_write_extent+0x19c/0x488 fs/hfs/extent.c:121 __hfs_ext_cache_extent+0x84/0x750 fs/hfs/extent.c:174 hfs_ext_read_extent fs/hfs/extent.c:202 [inline] hfs_extend_file+0x264/0xf4c fs/hfs/extent.c:401 hfs_get_block+0x2e8/0x9cc fs/hfs/extent.c:353 __block_write_begin_int+0x53c/0x15e8 fs/buffer.c:2145 block_write_begin fs/buffer.c:2256 [inline] cont_write_begin+0x62c/0x968 fs/buffer.c:2594 hfs_write_begin+0x7c/0xc4 fs/hfs/inode.c:52 cont_expand_zero fs/buffer.c:2522 [inline] cont_write_begin+0x26c/0x968 fs/buffer.c:2584 hfs_write_begin+0x7c/0xc4 fs/hfs/inode.c:52 hfs_file_truncate+0x158/0x7ec fs/hfs/extent.c:494 hfs_inode_setattr+0x398/0x554 fs/hfs/inode.c:654 notify_change+0x9a4/0xc50 fs/attr.c:552 do_truncate+0x198/0x210 fs/open.c:68 vfs_truncate+0x398/0x444 fs/open.c:118 do_sys_truncate+0xe4/0x1a8 fs/open.c:141 __do_sys_truncate fs/open.c:153 [inline] __se_sys_truncate fs/open.c:151 [inline] __arm64_sys_truncate+0x5c/0x74 fs/open.c:151 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 -> #0 (&tree->tree_lock#2/1){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x1774/0x30a4 kernel/locking/lockdep.c:5237 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5868 __mutex_lock_common+0x1d0/0x24ac kernel/locking/mutex.c:598 __mutex_lock kernel/locking/mutex.c:760 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:812 hfs_find_init+0x15c/0x1d8 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x238/0xf4c fs/hfs/extent.c:401 hfs_bmap_reserve+0xd4/0x3e0 fs/hfs/btree.c:269 hfs_cat_create+0x19c/0x590 fs/hfs/catalog.c:104 hfs_mkdir+0x6c/0xe4 fs/hfs/dir.c:232 vfs_mkdir+0x284/0x424 fs/namei.c:4366 do_mkdirat+0x1f8/0x4c8 fs/namei.c:4399 __do_sys_mkdirat fs/namei.c:4416 [inline] __se_sys_mkdirat fs/namei.c:4414 [inline] __arm64_sys_mkdirat+0x8c/0xa4 fs/namei.c:4414 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&HFS_I(tree->inode)->extents_lock); lock(&tree->tree_lock#2/1); lock(&HFS_I(tree->inode)->extents_lock); lock(&tree->tree_lock#2/1); *** DEADLOCK *** 4 locks held by syz.0.291/8425: #0: ffff0000cdbf4428 (sb_writers#25){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:557 #1: ffff0000cce30fa0 (&type->i_mutex_dir_key#17/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline] #1: ffff0000cce30fa0 (&type->i_mutex_dir_key#17/1){+.+.}-{4:4}, at: filename_create+0x1ac/0x32c fs/namei.c:4139 #2: ffff0000d02980b0 (&tree->tree_lock#2){+.+.}-{4:4}, at: hfs_find_init+0x15c/0x1d8 fs/hfs/bfind.c:-1 #3: ffff0000cce300f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xd4/0xf4c fs/hfs/extent.c:397 stack backtrace: CPU: 1 UID: 0 PID: 8425 Comm: syz.0.291 Not tainted 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 print_circular_bug+0x324/0x32c kernel/locking/lockdep.c:2043 check_noncircular+0x154/0x174 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x1774/0x30a4 kernel/locking/lockdep.c:5237 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5868 __mutex_lock_common+0x1d0/0x24ac kernel/locking/mutex.c:598 __mutex_lock kernel/locking/mutex.c:760 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:812 hfs_find_init+0x15c/0x1d8 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x238/0xf4c fs/hfs/extent.c:401 hfs_bmap_reserve+0xd4/0x3e0 fs/hfs/btree.c:269 hfs_cat_create+0x19c/0x590 fs/hfs/catalog.c:104 hfs_mkdir+0x6c/0xe4 fs/hfs/dir.c:232 vfs_mkdir+0x284/0x424 fs/namei.c:4366 do_mkdirat+0x1f8/0x4c8 fs/namei.c:4399 __do_sys_mkdirat fs/namei.c:4416 [inline] __se_sys_mkdirat fs/namei.c:4414 [inline] __arm64_sys_mkdirat+0x8c/0xa4 fs/namei.c:4414 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596