loop2: detected capacity change from 0 to 64 ============================================ WARNING: possible recursive locking detected syzkaller #0 Not tainted -------------------------------------------- syz.2.286/8038 is trying to acquire lock: ffff88805c5f8128 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397 but task is already holding lock: ffff88805c5f8868 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 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.2.286/8038: #0: ffff888039d92488 (sb_writers#35){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557 #1: ffff88805c5f9180 (&type->i_mutex_dir_key#23/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:915 [inline] #1: ffff88805c5f9180 (&type->i_mutex_dir_key#23/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0 fs/namei.c:4139 #2: ffff888031e440a0 (&tree->tree_lock){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1 #3: ffff88805c5f8868 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397 #4: ffff888031e460a0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1 stack backtrace: CPU: 0 UID: 0 PID: 8038 Comm: syz.2.286 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_deadlock_bug+0x28b/0x2a0 kernel/locking/lockdep.c:3041 check_deadlock kernel/locking/lockdep.c:3093 [inline] validate_chain+0x1a3f/0x2140 kernel/locking/lockdep.c:3895 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/rtmutex_api.c:535 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:547 hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397 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+0x316/0x1230 fs/hfs/extent.c:401 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 hfs_cat_create+0x1b3/0x640 fs/hfs/catalog.c:104 hfs_mkdir+0x6c/0xe0 fs/hfs/dir.c:232 vfs_mkdir+0x306/0x510 fs/namei.c:4366 do_mkdirat+0x247/0x590 fs/namei.c:4399 __do_sys_mkdirat fs/namei.c:4416 [inline] __se_sys_mkdirat fs/namei.c:4414 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4414 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f110236d417 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 02 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f11005d5e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f11005d5ef0 RCX: 00007f110236d417 RDX: 00000000000001ff RSI: 0000200000000100 RDI: 00000000ffffff9c RBP: 0000000000000000 R08: 0000200000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000100 R13: 00007f11005d5eb0 R14: 0000000000000000 R15: 0000000000000000 syz.2.286: attempt to access beyond end of device loop2: rw=0, sector=64, nr_sectors = 1 limit=64 Buffer I/O error on dev loop2, logical block 64, async page read syz.2.286: attempt to access beyond end of device loop2: rw=0, sector=65, nr_sectors = 1 limit=64 Buffer I/O error on dev loop2, logical block 65, async page read syz.2.286: attempt to access beyond end of device loop2: rw=0, sector=66, nr_sectors = 1 limit=64 Buffer I/O error on dev loop2, logical block 66, async page read syz.2.286: attempt to access beyond end of device loop2: rw=0, sector=64, nr_sectors = 1 limit=64 Buffer I/O error on dev loop2, logical block 64, async page read syz.2.286: attempt to access beyond end of device loop2: rw=0, sector=65, nr_sectors = 1 limit=64 Buffer I/O error on dev loop2, logical block 65, async page read syz.2.286: attempt to access beyond end of device loop2: rw=0, sector=66, nr_sectors = 1 limit=64 Buffer I/O error on dev loop2, logical block 66, async page read syz.2.286: attempt to access beyond end of device loop2: rw=0, sector=64, nr_sectors = 1 limit=64 Buffer I/O error on dev loop2, logical block 64, async page read syz.2.286: attempt to access beyond end of device loop2: rw=0, sector=65, nr_sectors = 1 limit=64 Buffer I/O error on dev loop2, logical block 65, async page read syz.2.286: attempt to access beyond end of device loop2: rw=0, sector=66, nr_sectors = 1 limit=64 Buffer I/O error on dev loop2, logical block 66, async page read syz.2.286: attempt to access beyond end of device loop2: rw=0, sector=64, nr_sectors = 1 limit=64 Buffer I/O error on dev loop2, logical block 64, async page read