loop0: detected capacity change from 0 to 4096 ====================================================== WARNING: possible circular locking dependency detected 5.15.185-syzkaller #0 Not tainted ------------------------------------------------------ syz.0.51/4494 is trying to acquire lock: ffff88801e900828 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock+0x1c/0x50 include/linux/mmap_lock.h:117 but task is already holding lock: ffff8880742fa120 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_trylock include/linux/fs.h:807 [inline] ffff8880742fa120 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ntfs_file_write_iter+0x1d1/0x590 fs/ntfs3/file.c:1123 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}: down_write+0x38/0x60 kernel/locking/rwsem.c:1551 inode_lock include/linux/fs.h:787 [inline] ntfs_file_mmap+0x516/0x720 fs/ntfs3/file.c:401 call_mmap include/linux/fs.h:2177 [inline] mmap_file+0x5d/0xb0 mm/util.c:1092 __mmap_region mm/mmap.c:1784 [inline] mmap_region+0xd0d/0x15e0 mm/mmap.c:2921 do_mmap+0x77a/0xdf0 mm/mmap.c:1574 vm_mmap_pgoff+0x1b2/0x2b0 mm/util.c:551 ksys_mmap_pgoff+0x542/0x780 mm/mmap.c:1623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #0 (&mm->mmap_lock){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498 mmap_read_lock+0x1c/0x50 include/linux/mmap_lock.h:117 do_user_addr_fault+0xc35/0xc80 arch/x86/mm/fault.c:1308 handle_page_fault arch/x86/mm/fault.c:1445 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1501 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 __get_user_nocheck_1+0x6/0x10 arch/x86/lib/getuser.S:103 fault_in_readable+0xc5/0x150 mm/gup.c:1801 fault_in_iov_iter_readable+0x11e/0x270 lib/iov_iter.c:460 generic_perform_write+0x199/0x530 mm/filemap.c:3775 __generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912 ntfs_file_write_iter+0x4d5/0x590 fs/ntfs3/file.c:1144 call_write_iter include/linux/fs.h:2172 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x712/0xd00 fs/read_write.c:594 ksys_write+0x14d/0x250 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#21); lock(&mm->mmap_lock); lock(&sb->s_type->i_mutex_key#21); lock(&mm->mmap_lock); *** DEADLOCK *** 3 locks held by syz.0.51/4494: #0: ffff8880786ea370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2bf/0x370 fs/file.c:1058 #1: ffff88807b330460 (sb_writers#15){.+.+}-{0:0}, at: vfs_write+0x28a/0xd00 fs/read_write.c:590 #2: ffff8880742fa120 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_trylock include/linux/fs.h:807 [inline] #2: ffff8880742fa120 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ntfs_file_write_iter+0x1d1/0x590 fs/ntfs3/file.c:1123 stack backtrace: CPU: 1 PID: 4494 Comm: syz.0.51 Not tainted 5.15.185-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2133 check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498 mmap_read_lock+0x1c/0x50 include/linux/mmap_lock.h:117 do_user_addr_fault+0xc35/0xc80 arch/x86/mm/fault.c:1308 handle_page_fault arch/x86/mm/fault.c:1445 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1501 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0010:__get_user_nocheck_1+0x6/0x10 arch/x86/lib/getuser.S:124 Code: d0 73 64 48 19 d2 48 21 d0 0f 01 cb 48 8b 10 31 c0 0f 01 ca c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 01 cb 0f ae e8 <0f> b6 10 31 c0 0f 01 ca c3 90 0f 01 cb 0f ae e8 0f b7 10 31 c0 0f RSP: 0018:ffffc90003407a20 EFLAGS: 00050287 RAX: 000020000007c000 RBX: 0000000000001000 RCX: 0000000000080000 RDX: ffffc90004bf1000 RSI: 000000000004ffb4 RDI: 000000000004ffb5 RBP: 00000000ffffffff R08: dffffc0000000000 R09: fffff9400038c3b7 R10: fffff9400038c3b7 R11: 1ffffd400038c3b6 R12: 00000000ffffffff R13: 000020000007d000 R14: 000020000007b6c7 R15: 000020000007c000 fault_in_readable+0xc5/0x150 mm/gup.c:1801 fault_in_iov_iter_readable+0x11e/0x270 lib/iov_iter.c:460 generic_perform_write+0x199/0x530 mm/filemap.c:3775 __generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912 ntfs_file_write_iter+0x4d5/0x590 fs/ntfs3/file.c:1144 call_write_iter include/linux/fs.h:2172 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x712/0xd00 fs/read_write.c:594 ksys_write+0x14d/0x250 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fcb139f8929 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:00007fcb11860038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fcb13c1ffa0 RCX: 00007fcb139f8929 RDX: 000000000208e24b RSI: 0000200000000040 RDI: 0000000000000006 RBP: 00007fcb13a7ab39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fcb13c1ffa0 R15: 00007ffe1ae7ebd8 ntfs3: loop0: ino=21, "file1" failed to extend initialized size to e7c. ---------------- Code disassembly (best guess): 0: d0 73 64 shlb 0x64(%rbx) 3: 48 19 d2 sbb %rdx,%rdx 6: 48 21 d0 and %rdx,%rax 9: 0f 01 cb stac c: 48 8b 10 mov (%rax),%rdx f: 31 c0 xor %eax,%eax 11: 0f 01 ca clac 14: c3 ret 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: 90 nop 23: 90 nop 24: 0f 01 cb stac 27: 0f ae e8 lfence * 2a: 0f b6 10 movzbl (%rax),%edx <-- trapping instruction 2d: 31 c0 xor %eax,%eax 2f: 0f 01 ca clac 32: c3 ret 33: 90 nop 34: 0f 01 cb stac 37: 0f ae e8 lfence 3a: 0f b7 10 movzwl (%rax),%edx 3d: 31 c0 xor %eax,%eax 3f: 0f .byte 0xf