====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.4.900/16815 is trying to acquire lock: ffff88804017c9d0 (mapping.invalidate_lock#6){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1089 [inline] ffff88804017c9d0 (mapping.invalidate_lock#6){++++}-{4:4}, at: filemap_fault+0x6e0/0x13c0 mm/filemap.c:3570 but task is already holding lock: ffff88801b3211b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:611 [inline] ffff88801b3211b0 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:441 [inline] ffff88801b3211b0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x36/0x340 mm/mmap_lock.c:501 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&mm->mmap_lock){++++}-{4:4}: down_read_killable+0xa4/0x220 kernel/locking/rwsem.c:1599 mmap_read_lock_killable+0x1d/0x70 include/linux/mmap_lock.h:601 get_mmap_lock_carefully mm/mmap_lock.c:450 [inline] lock_mm_and_find_vma+0x2d6/0x340 mm/mmap_lock.c:501 do_user_addr_fault+0x341/0x1340 arch/x86/mm/fault.c:1366 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 filldir+0x2bd/0x630 fs/readdir.c:-1 dir_emit include/linux/fs.h:3587 [inline] ntfs_dir_emit fs/ntfs3/dir.c:346 [inline] ntfs_read_hdr+0x8a4/0xc10 fs/ntfs3/dir.c:387 ntfs_readdir+0x9ea/0xec0 fs/ntfs3/dir.c:547 iterate_dir+0x2f1/0x4e0 fs/readdir.c:110 __do_sys_getdents fs/readdir.c:319 [inline] __se_sys_getdents+0xf1/0x270 fs/readdir.c:304 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&ni->ni_lock#2/5){+.+.}-{4:4}: __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 ni_lock fs/ntfs3/ntfs_fs.h:1222 [inline] ntfs_fallocate+0x914/0xf70 fs/ntfs3/file.c:617 vfs_fallocate+0x663/0x7f0 fs/open.c:338 ksys_fallocate fs/open.c:362 [inline] __do_sys_fallocate fs/open.c:367 [inline] __se_sys_fallocate fs/open.c:365 [inline] __x64_sys_fallocate+0xbf/0x110 fs/open.c:365 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (mapping.invalidate_lock#6){++++}-{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+0x1520/0x2ce0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 down_read+0x97/0x200 kernel/locking/rwsem.c:1574 filemap_invalidate_lock_shared include/linux/fs.h:1089 [inline] filemap_fault+0x6e0/0x13c0 mm/filemap.c:3570 __do_fault+0x138/0x2a0 mm/memory.c:5425 do_read_fault mm/memory.c:5860 [inline] do_fault mm/memory.c:5994 [inline] do_pte_missing+0x1828/0x28f0 mm/memory.c:4566 handle_pte_fault mm/memory.c:6379 [inline] __handle_mm_fault mm/memory.c:6517 [inline] handle_mm_fault+0xd28/0x13f0 mm/memory.c:6686 do_user_addr_fault+0x744/0x1340 arch/x86/mm/fault.c:1394 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 do_strncpy_from_user lib/strncpy_from_user.c:-1 [inline] strncpy_from_user+0xb7/0x2c0 lib/strncpy_from_user.c:130 do_getname+0x77/0x250 fs/namei.c:198 getname include/linux/fs.h:2537 [inline] class_filename_constructor include/linux/fs.h:2564 [inline] ksys_truncate+0xa0/0x1c0 fs/open.c:138 __do_sys_truncate fs/open.c:154 [inline] __se_sys_truncate fs/open.c:152 [inline] __x64_sys_truncate+0x5b/0x70 fs/open.c:152 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: mapping.invalidate_lock#6 --> &ni->ni_lock#2/5 --> &mm->mmap_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(&mm->mmap_lock); lock(&ni->ni_lock#2/5); lock(&mm->mmap_lock); rlock(mapping.invalidate_lock#6); *** DEADLOCK *** 1 lock held by syz.4.900/16815: #0: ffff88801b3211b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:611 [inline] #0: ffff88801b3211b0 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:441 [inline] #0: ffff88801b3211b0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x36/0x340 mm/mmap_lock.c:501 stack backtrace: CPU: 1 UID: 0 PID: 16815 Comm: syz.4.900 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2043 check_noncircular+0x12e/0x150 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+0x1520/0x2ce0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 down_read+0x97/0x200 kernel/locking/rwsem.c:1574 filemap_invalidate_lock_shared include/linux/fs.h:1089 [inline] filemap_fault+0x6e0/0x13c0 mm/filemap.c:3570 __do_fault+0x138/0x2a0 mm/memory.c:5425 do_read_fault mm/memory.c:5860 [inline] do_fault mm/memory.c:5994 [inline] do_pte_missing+0x1828/0x28f0 mm/memory.c:4566 handle_pte_fault mm/memory.c:6379 [inline] __handle_mm_fault mm/memory.c:6517 [inline] handle_mm_fault+0xd28/0x13f0 mm/memory.c:6686 do_user_addr_fault+0x744/0x1340 arch/x86/mm/fault.c:1394 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0010:do_strncpy_from_user lib/strncpy_from_user.c:41 [inline] RIP: 0010:strncpy_from_user+0xb7/0x2c0 lib/strncpy_from_user.c:130 Code: 00 00 4c 89 f6 e8 09 b2 c6 fc 49 83 fe 07 0f 86 9d 00 00 00 4c 89 24 24 4c 89 74 24 08 48 c7 c5 f8 ff ff ff 45 31 ff 49 89 dc <4e> 8b 34 3b 48 b8 ff fe fe fe fe fe fe fe 49 8d 1c 06 4d 89 f5 49 RSP: 0018:ffffc9000468fd98 EFLAGS: 00050246 RAX: ffffffff84fe8be7 RBX: 0000200000000280 RCX: ffff8880314c0000 RDX: 0000000000000002 RSI: 00000000000000a8 RDI: 0000000000000007 RBP: fffffffffffffff8 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed100d14a178 R12: 0000200000000280 R13: 0000200000000280 R14: 00000000000000a8 R15: 0000000000000000 do_getname+0x77/0x250 fs/namei.c:198 getname include/linux/fs.h:2537 [inline] class_filename_constructor include/linux/fs.h:2564 [inline] ksys_truncate+0xa0/0x1c0 fs/open.c:138 __do_sys_truncate fs/open.c:154 [inline] __se_sys_truncate fs/open.c:152 [inline] __x64_sys_truncate+0x5b/0x70 fs/open.c:152 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f916b36de99 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:00007f91695c6028 EFLAGS: 00000246 ORIG_RAX: 000000000000004c RAX: ffffffffffffffda RBX: 00007f916b5f5fa0 RCX: 00007f916b36de99 RDX: 0000000000000000 RSI: 0000000000001bf8 RDI: 0000200000000280 RBP: 00007f916b403eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f916b5f6038 R14: 00007f916b5f5fa0 R15: 00007ffd684ceb18 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 4c 89 f6 mov %r14,%rsi 5: e8 09 b2 c6 fc call 0xfcc6b213 a: 49 83 fe 07 cmp $0x7,%r14 e: 0f 86 9d 00 00 00 jbe 0xb1 14: 4c 89 24 24 mov %r12,(%rsp) 18: 4c 89 74 24 08 mov %r14,0x8(%rsp) 1d: 48 c7 c5 f8 ff ff ff mov $0xfffffffffffffff8,%rbp 24: 45 31 ff xor %r15d,%r15d 27: 49 89 dc mov %rbx,%r12 * 2a: 4e 8b 34 3b mov (%rbx,%r15,1),%r14 <-- trapping instruction 2e: 48 b8 ff fe fe fe fe movabs $0xfefefefefefefeff,%rax 35: fe fe fe 38: 49 8d 1c 06 lea (%r14,%rax,1),%rbx 3c: 4d 89 f5 mov %r14,%r13 3f: 49 rex.WB