loop0: detected capacity change from 0 to 1024 usb 1-1: USB disconnect, device number 2 ====================================================== WARNING: possible circular locking dependency detected 6.15.0-rc2-syzkaller-00048-gc62f4b82d571 #0 Not tainted ------------------------------------------------------ syz.0.0/5334 is trying to acquire lock: ffff8880535320f8 (&sbi->alloc_mutex){+.+.}-{4:4}, at: hfsplus_block_allocate+0x9e/0x8c0 fs/hfsplus/bitmap.c:35 but task is already holding lock: ffff888053543048 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x21d/0x1b70 fs/hfsplus/extents.c:458 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}: lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 __mutex_lock_common kernel/locking/mutex.c:601 [inline] __mutex_lock+0x1a5/0x10c0 kernel/locking/mutex.c:746 hfsplus_get_block+0x385/0x14f0 fs/hfsplus/extents.c:260 block_read_full_folio+0x2d3/0x850 fs/buffer.c:2392 filemap_read_folio+0x14a/0x3b0 mm/filemap.c:2400 do_read_cache_folio+0x373/0x5b0 mm/filemap.c:3884 do_read_cache_page mm/filemap.c:3950 [inline] read_cache_page+0x5b/0x170 mm/filemap.c:3959 read_mapping_page include/linux/pagemap.h:989 [inline] hfsplus_block_allocate+0xee/0x8c0 fs/hfsplus/bitmap.c:37 hfsplus_file_extend+0xae0/0x1b70 fs/hfsplus/extents.c:469 hfsplus_get_block+0x408/0x14f0 fs/hfsplus/extents.c:245 __block_write_begin_int+0x691/0x1930 fs/buffer.c:2116 block_write_begin fs/buffer.c:2227 [inline] cont_write_begin+0x781/0xb40 fs/buffer.c:2566 hfsplus_write_begin+0x68/0xb0 fs/hfsplus/inode.c:46 cont_expand_zero fs/buffer.c:2493 [inline] cont_write_begin+0x32d/0xb40 fs/buffer.c:2556 hfsplus_write_begin+0x68/0xb0 fs/hfsplus/inode.c:46 generic_perform_write+0x329/0xa10 mm/filemap.c:4102 generic_file_write_iter+0x10e/0x5e0 mm/filemap.c:4245 do_iter_readv_writev+0x71f/0x9d0 fs/read_write.c:-1 vfs_writev+0x38d/0xbc0 fs/read_write.c:1055 do_pwritev fs/read_write.c:1151 [inline] __do_sys_pwritev2 fs/read_write.c:1209 [inline] __se_sys_pwritev2+0x1b8/0x2d0 fs/read_write.c:1200 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&sbi->alloc_mutex){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain+0xa69/0x24e0 kernel/locking/lockdep.c:3909 __lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235 lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 __mutex_lock_common kernel/locking/mutex.c:601 [inline] __mutex_lock+0x1a5/0x10c0 kernel/locking/mutex.c:746 hfsplus_block_allocate+0x9e/0x8c0 fs/hfsplus/bitmap.c:35 hfsplus_file_extend+0xae0/0x1b70 fs/hfsplus/extents.c:469 hfsplus_get_block+0x408/0x14f0 fs/hfsplus/extents.c:245 __block_write_begin_int+0x691/0x1930 fs/buffer.c:2116 block_write_begin fs/buffer.c:2227 [inline] cont_write_begin+0x781/0xb40 fs/buffer.c:2566 hfsplus_write_begin+0x68/0xb0 fs/hfsplus/inode.c:46 cont_expand_zero fs/buffer.c:2493 [inline] cont_write_begin+0x32d/0xb40 fs/buffer.c:2556 hfsplus_write_begin+0x68/0xb0 fs/hfsplus/inode.c:46 generic_cont_expand_simple+0x191/0x2b0 fs/buffer.c:2457 hfsplus_setattr+0x16d/0x270 fs/hfsplus/inode.c:258 notify_change+0xbca/0xe90 fs/attr.c:552 do_truncate+0x222/0x310 fs/open.c:65 vfs_truncate+0x4a6/0x540 fs/open.c:115 do_sys_truncate+0xd8/0x190 fs/open.c:138 __do_sys_truncate fs/open.c:150 [inline] __se_sys_truncate fs/open.c:148 [inline] __x64_sys_truncate+0x5b/0x70 fs/open.c:148 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 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(&sbi->alloc_mutex); lock(&HFSPLUS_I(inode)->extents_lock); lock(&sbi->alloc_mutex); *** DEADLOCK *** 3 locks held by syz.0.0/5334: #0: ffff8880120c2420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556 #1: ffff888053543238 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff888053543238 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: do_truncate+0x20e/0x310 fs/open.c:63 #2: ffff888053543048 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x21d/0x1b70 fs/hfsplus/extents.c:458 stack backtrace: CPU: 0 UID: 0 PID: 5334 Comm: syz.0.0 Not tainted 6.15.0-rc2-syzkaller-00048-gc62f4b82d571 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2079 check_noncircular+0x142/0x160 kernel/locking/lockdep.c:2211 check_prev_add kernel/locking/lockdep.c:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain+0xa69/0x24e0 kernel/locking/lockdep.c:3909 __lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235 lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 __mutex_lock_common kernel/locking/mutex.c:601 [inline] __mutex_lock+0x1a5/0x10c0 kernel/locking/mutex.c:746 hfsplus_block_allocate+0x9e/0x8c0 fs/hfsplus/bitmap.c:35 hfsplus_file_extend+0xae0/0x1b70 fs/hfsplus/extents.c:469 hfsplus_get_block+0x408/0x14f0 fs/hfsplus/extents.c:245 __block_write_begin_int+0x691/0x1930 fs/buffer.c:2116 block_write_begin fs/buffer.c:2227 [inline] cont_write_begin+0x781/0xb40 fs/buffer.c:2566 hfsplus_write_begin+0x68/0xb0 fs/hfsplus/inode.c:46 cont_expand_zero fs/buffer.c:2493 [inline] cont_write_begin+0x32d/0xb40 fs/buffer.c:2556 hfsplus_write_begin+0x68/0xb0 fs/hfsplus/inode.c:46 generic_cont_expand_simple+0x191/0x2b0 fs/buffer.c:2457 hfsplus_setattr+0x16d/0x270 fs/hfsplus/inode.c:258 notify_change+0xbca/0xe90 fs/attr.c:552 do_truncate+0x222/0x310 fs/open.c:65 vfs_truncate+0x4a6/0x540 fs/open.c:115 do_sys_truncate+0xd8/0x190 fs/open.c:138 __do_sys_truncate fs/open.c:150 [inline] __se_sys_truncate fs/open.c:148 [inline] __x64_sys_truncate+0x5b/0x70 fs/open.c:148 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3eabf8e169 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3eacde3038 EFLAGS: 00000246 ORIG_RAX: 000000000000004c RAX: ffffffffffffffda RBX: 00007f3eac1b5fa0 RCX: 00007f3eabf8e169 RDX: 0000000000000000 RSI: 0000000000007fff RDI: 0000200000000040 RBP: 00007f3eac010a68 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f3eac1b5fa0 R15: 00007ffdf766a748