loop3: detected capacity change from 0 to 64 ============================================ WARNING: possible recursive locking detected syzkaller #0 Not tainted -------------------------------------------- syz.3.131/7227 is trying to acquire lock: ffff0000dd6c0778 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xd4/0x10e4 fs/hfs/extent.c:397 but task is already holding lock: ffff0000dd6c00f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xd4/0x10e4 fs/hfs/extent.c:397 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&HFS_I(tree->inode)->extents_lock); lock(&HFS_I(tree->inode)->extents_lock); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by syz.3.131/7227: #0: ffff0000d7a08420 (sb_writers#24){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:508 #1: ffff0000dd6c0fa0 (&type->i_mutex_dir_key#15){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline] #1: ffff0000dd6c0fa0 (&type->i_mutex_dir_key#15){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:3892 [inline] #1: ffff0000dd6c0fa0 (&type->i_mutex_dir_key#15){+.+.}-{4:4}, at: path_openat+0x638/0x2c40 fs/namei.c:4131 #2: ffff0001031f60b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfs_find_init+0x168/0x28c fs/hfs/bfind.c:-1 #3: ffff0000dd6c00f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xd4/0x10e4 fs/hfs/extent.c:397 #4: ffff0001031f40b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x168/0x28c fs/hfs/bfind.c:-1 stack backtrace: CPU: 0 UID: 0 PID: 7227 Comm: syz.3.131 Not tainted syzkaller #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_deadlock_bug+0x2e8/0x2f0 kernel/locking/lockdep.c:3041 check_deadlock kernel/locking/lockdep.c:3093 [inline] validate_chain kernel/locking/lockdep.c:3895 [inline] __lock_acquire+0x2940/0x30a4 kernel/locking/lockdep.c:5237 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5868 __mutex_lock_common+0x1d0/0x2678 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+0xd4/0x10e4 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+0x258/0x10e4 fs/hfs/extent.c:401 hfs_bmap_reserve+0xd4/0x3e0 fs/hfs/btree.c:269 hfs_cat_create+0x1a4/0x65c fs/hfs/catalog.c:104 hfs_create+0x6c/0xe0 fs/hfs/dir.c:202 lookup_open fs/namei.c:3796 [inline] open_last_lookups fs/namei.c:3895 [inline] path_openat+0x12d8/0x2c40 fs/namei.c:4131 do_filp_open+0x18c/0x36c fs/namei.c:4161 do_sys_openat2+0x11c/0x1b4 fs/open.c:1437 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __arm64_sys_openat+0x120/0x158 fs/open.c:1463 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x254 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+0x5c/0x254 arch/arm64/kernel/entry-common.c:746 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:765 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 syz.3.131: attempt to access beyond end of device loop3: rw=0, sector=66, nr_sectors = 1 limit=64 Buffer I/O error on dev loop3, logical block 66, async page read syz.3.131: attempt to access beyond end of device loop3: rw=0, sector=67, nr_sectors = 1 limit=64 Buffer I/O error on dev loop3, logical block 67, async page read syz.3.131: attempt to access beyond end of device loop3: rw=0, sector=68, nr_sectors = 1 limit=64 Buffer I/O error on dev loop3, logical block 68, async page read syz.3.131: attempt to access beyond end of device loop3: rw=0, sector=69, nr_sectors = 1 limit=64 Buffer I/O error on dev loop3, logical block 69, async page read Buffer I/O error on dev loop3, logical block 70, async page read Buffer I/O error on dev loop3, logical block 66, async page read Buffer I/O error on dev loop3, logical block 67, async page read Buffer I/O error on dev loop3, logical block 68, async page read Buffer I/O error on dev loop3, logical block 69, async page read Buffer I/O error on dev loop3, logical block 70, async page read