loop1: detected capacity change from 0 to 1024 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.1.437/7567 is trying to acquire lock: ffff8880761f60b0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfsplus_find_init+0x18f/0x2f0 fs/hfsplus/bfind.c:28 but task is already holding lock: ffff888055220108 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1c2/0x11d0 fs/hfsplus/extents.c:453 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776 hfsplus_file_extend+0x1c2/0x11d0 fs/hfsplus/extents.c:453 hfsplus_bmap_reserve+0x322/0x420 fs/hfsplus/btree.c:358 __hfsplus_ext_write_extent+0x474/0x5e0 fs/hfsplus/extents.c:104 __hfsplus_ext_cache_extent+0x98/0x9d0 fs/hfsplus/extents.c:186 hfsplus_ext_read_extent+0x200/0x250 fs/hfsplus/extents.c:218 hfsplus_file_extend+0x719/0x11d0 fs/hfsplus/extents.c:457 hfsplus_get_block+0x1a9/0xab0 fs/hfsplus/extents.c:245 __block_write_begin_int+0x57a/0x19c0 fs/buffer.c:2146 block_write_begin+0x9d/0x1d0 fs/buffer.c:2257 cont_write_begin+0x573/0xa10 fs/buffer.c:2595 hfsplus_write_begin+0x64/0x120 fs/hfsplus/inode.c:48 generic_perform_write+0x292/0xa40 mm/filemap.c:4314 __generic_file_write_iter+0x1f7/0x240 mm/filemap.c:4431 generic_file_write_iter+0xe1/0x3d0 mm/filemap.c:4457 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1070 fs/read_write.c:688 ksys_write+0x12a/0x250 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #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+0x14b8/0x2630 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x17c/0x330 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776 hfsplus_find_init+0x18f/0x2f0 fs/hfsplus/bfind.c:28 hfsplus_ext_read_extent+0x190/0x250 fs/hfsplus/extents.c:216 hfsplus_file_extend+0x719/0x11d0 fs/hfsplus/extents.c:457 hfsplus_get_block+0x1a9/0xab0 fs/hfsplus/extents.c:245 __block_write_begin_int+0x57a/0x19c0 fs/buffer.c:2146 block_write_begin+0x9d/0x1d0 fs/buffer.c:2257 cont_write_begin+0x573/0xa10 fs/buffer.c:2595 hfsplus_write_begin+0x64/0x120 fs/hfsplus/inode.c:48 cont_expand_zero fs/buffer.c:2523 [inline] cont_write_begin+0x2b9/0xa10 fs/buffer.c:2585 hfsplus_write_begin+0x64/0x120 fs/hfsplus/inode.c:48 generic_cont_expand_simple+0x122/0x200 fs/buffer.c:2486 hfsplus_setattr+0x250/0x320 fs/hfsplus/inode.c:280 notify_change+0xb25/0x1330 fs/attr.c:546 do_truncate+0x1df/0x240 fs/open.c:68 vfs_truncate+0x538/0x720 fs/open.c:118 do_sys_truncate+0xee/0x190 fs/open.c:142 __do_sys_truncate fs/open.c:154 [inline] __se_sys_truncate fs/open.c:152 [inline] __x64_sys_truncate+0x54/0x80 fs/open.c:152 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&HFSPLUS_I(inode)->extents_lock); lock(&tree->tree_lock#2/1); lock(&HFSPLUS_I(inode)->extents_lock); lock(&tree->tree_lock#2/1); *** DEADLOCK *** 3 locks held by syz.1.437/7567: #0: ffff8880761f4420 (sb_writers#22){.+.+}-{0:0}, at: vfs_truncate+0x336/0x720 fs/open.c:96 #1: ffff8880552202f8 (&sb->s_type->i_mutex_key#37){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1033 [inline] #1: ffff8880552202f8 (&sb->s_type->i_mutex_key#37){+.+.}-{4:4}, at: do_truncate+0x14e/0x240 fs/open.c:63 #2: ffff888055220108 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1c2/0x11d0 fs/hfsplus/extents.c:453 stack backtrace: CPU: 0 UID: 0 PID: 7567 Comm: syz.1.437 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_circular_bug.cold+0x178/0x1c7 kernel/locking/lockdep.c:2043 check_noncircular+0x146/0x160 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+0x14b8/0x2630 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x17c/0x330 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776 hfsplus_find_init+0x18f/0x2f0 fs/hfsplus/bfind.c:28 hfsplus_ext_read_extent+0x190/0x250 fs/hfsplus/extents.c:216 hfsplus_file_extend+0x719/0x11d0 fs/hfsplus/extents.c:457 hfsplus_get_block+0x1a9/0xab0 fs/hfsplus/extents.c:245 __block_write_begin_int+0x57a/0x19c0 fs/buffer.c:2146 block_write_begin+0x9d/0x1d0 fs/buffer.c:2257 cont_write_begin+0x573/0xa10 fs/buffer.c:2595 hfsplus_write_begin+0x64/0x120 fs/hfsplus/inode.c:48 cont_expand_zero fs/buffer.c:2523 [inline] cont_write_begin+0x2b9/0xa10 fs/buffer.c:2585 hfsplus_write_begin+0x64/0x120 fs/hfsplus/inode.c:48 generic_cont_expand_simple+0x122/0x200 fs/buffer.c:2486 hfsplus_setattr+0x250/0x320 fs/hfsplus/inode.c:280 notify_change+0xb25/0x1330 fs/attr.c:546 do_truncate+0x1df/0x240 fs/open.c:68 vfs_truncate+0x538/0x720 fs/open.c:118 do_sys_truncate+0xee/0x190 fs/open.c:142 __do_sys_truncate fs/open.c:154 [inline] __se_sys_truncate fs/open.c:152 [inline] __x64_sys_truncate+0x54/0x80 fs/open.c:152 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd02e39bf79 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:00007fd02f2ab028 EFLAGS: 00000246 ORIG_RAX: 000000000000004c RAX: ffffffffffffffda RBX: 00007fd02e615fa0 RCX: 00007fd02e39bf79 RDX: 0000000000000000 RSI: 000000400000f000 RDI: 0000200000000080 RBP: 00007fd02e4327e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd02e616038 R14: 00007fd02e615fa0 R15: 00007ffdb762e118