loop0: detected capacity change from 0 to 64 ====================================================== WARNING: possible circular locking dependency detected 6.1.146-syzkaller #0 Not tainted ------------------------------------------------------ syz.0.304/5271 is trying to acquire lock: ffff0000cb1c1af8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xd4/0xf9c fs/hfs/extent.c:397 but task is already holding lock: ffff0000dd45e0b0 (&tree->tree_lock#2/1){+.+.}-{3:3}, at: hfs_find_init+0x148/0x1c8 fs/hfs/bfind.c:-1 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+0x190/0x1f38 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 hfs_find_init+0x148/0x1c8 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x238/0xf9c fs/hfs/extent.c:401 hfs_bmap_reserve+0xd4/0x3e0 fs/hfs/btree.c:234 hfs_cat_create+0x1a0/0x758 fs/hfs/catalog.c:104 hfs_create+0x6c/0xe0 fs/hfs/dir.c:202 lookup_open fs/namei.c:3482 [inline] open_last_lookups fs/namei.c:3550 [inline] path_openat+0x112c/0x2680 fs/namei.c:3780 do_filp_open+0x174/0x344 fs/namei.c:3810 file_open_name fs/open.c:1263 [inline] filp_open+0x15c/0x1b8 fs/open.c:1283 do_coredump+0x1540/0x1c4c fs/coredump.c:765 get_signal+0xdec/0x1310 kernel/signal.c:2857 do_signal arch/arm64/kernel/signal.c:1081 [inline] do_notify_resume+0x290/0x2b0c arch/arm64/kernel/signal.c:1134 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_da+0xb4/0x154 arch/arm64/kernel/entry-common.c:516 el0t_64_sync_handler+0x90/0xf0 arch/arm64/kernel/entry-common.c:658 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #0 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x293c/0x6544 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x1f38 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 hfs_extend_file+0xd4/0xf9c fs/hfs/extent.c:397 hfs_bmap_reserve+0xd4/0x3e0 fs/hfs/btree.c:234 __hfs_ext_write_extent+0x19c/0x488 fs/hfs/extent.c:121 hfs_ext_write_extent+0x144/0x1bc fs/hfs/extent.c:144 hfs_write_inode+0xbc/0x880 fs/hfs/inode.c:434 write_inode fs/fs-writeback.c:1460 [inline] __writeback_single_inode+0x5e0/0x157c fs/fs-writeback.c:1677 writeback_single_inode+0x1c0/0x720 fs/fs-writeback.c:1733 write_inode_now+0x144/0x1b0 fs/fs-writeback.c:2769 hfs_file_fsync+0xa8/0x144 fs/hfs/inode.c:682 vfs_fsync_range+0x168/0x188 fs/sync.c:188 generic_write_sync include/linux/fs.h:2962 [inline] generic_file_write_iter+0x224/0x2b0 mm/filemap.c:4010 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x5ac/0x7c4 fs/read_write.c:584 ksys_write+0x120/0x210 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:646 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 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 *** 4 locks held by syz.0.304/5271: #0: ffff0000d966bc68 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x114/0x16c fs/file.c:1040 #1: ffff0000d418c460 (sb_writers#20){.+.+}-{0:0}, at: vfs_write+0x23c/0x7c4 fs/read_write.c:580 #2: ffff0000cb1c2328 (&sb->s_type->i_mutex_key#25){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #2: ffff0000cb1c2328 (&sb->s_type->i_mutex_key#25){+.+.}-{3:3}, at: hfs_file_fsync+0x9c/0x144 fs/hfs/inode.c:679 #3: ffff0000dd45e0b0 (&tree->tree_lock#2/1){+.+.}-{3:3}, at: hfs_find_init+0x148/0x1c8 fs/hfs/bfind.c:-1 stack backtrace: CPU: 0 PID: 5271 Comm: syz.0.304 Not tainted 6.1.146-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106 dump_stack+0x1c/0x5c lib/dump_stack.c:113 print_circular_bug+0x148/0x1b0 kernel/locking/lockdep.c:2048 check_noncircular+0x240/0x2d4 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x293c/0x6544 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x1f38 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 hfs_extend_file+0xd4/0xf9c fs/hfs/extent.c:397 hfs_bmap_reserve+0xd4/0x3e0 fs/hfs/btree.c:234 __hfs_ext_write_extent+0x19c/0x488 fs/hfs/extent.c:121 hfs_ext_write_extent+0x144/0x1bc fs/hfs/extent.c:144 hfs_write_inode+0xbc/0x880 fs/hfs/inode.c:434 write_inode fs/fs-writeback.c:1460 [inline] __writeback_single_inode+0x5e0/0x157c fs/fs-writeback.c:1677 writeback_single_inode+0x1c0/0x720 fs/fs-writeback.c:1733 write_inode_now+0x144/0x1b0 fs/fs-writeback.c:2769 hfs_file_fsync+0xa8/0x144 fs/hfs/inode.c:682 vfs_fsync_range+0x168/0x188 fs/sync.c:188 generic_write_sync include/linux/fs.h:2962 [inline] generic_file_write_iter+0x224/0x2b0 mm/filemap.c:4010 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x5ac/0x7c4 fs/read_write.c:584 ksys_write+0x120/0x210 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:646 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585