syzbot


possible deadlock in ntfs_file_write_iter

Status: upstream: reported C repro on 2024/08/03 11:07
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+01244cf1d56776f863c8@syzkaller.appspotmail.com
First crash: 346d, last: 7d00h
Bug presence (2)
Date Name Commit Repro Result
2024/11/13 linux-6.1.y (ToT) d7039b844a1c C [report] possible deadlock in ntfs_file_write_iter
2024/11/13 upstream (ToT) 9f8e716d46c6 C Didn't crash
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 possible deadlock in ntfs_file_write_iter origin:lts-only 4 C inconclusive 294 9d20h 330d 0/3 upstream: reported C repro on 2024/08/19 12:03
upstream possible deadlock in ntfs_file_write_iter ntfs3 4 C done 131 6h17m 395d 0/29 upstream: reported C repro on 2024/06/15 08:45
linux-6.6 possible deadlock in ntfs_file_write_iter 4 10 1d14h 19d 0/2 upstream: reported on 2025/06/26 14:52
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2025/06/06 09:24 1h54m fix candidate upstream error job log
2025/04/28 18:45 3h00m fix candidate upstream error job log

Sample crash report:
         option from the mount to silence this warning.
=======================================================
======================================================
WARNING: possible circular locking dependency detected
6.1.116-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor352/4289 is trying to acquire lock:
ffff0000d4fb2548 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0x9c/0x124 mm/memory.c:5850

but task is already holding lock:
ffff0000e5007240 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}, at: inode_trylock include/linux/fs.h:778 [inline]
ffff0000e5007240 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}, at: ntfs_file_write_iter+0x190/0x580 fs/ntfs3/file.c:1144

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}:
       down_write+0x5c/0x88 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:758 [inline]
       ntfs_file_mmap+0x4b0/0x688 fs/ntfs3/file.c:399
       call_mmap include/linux/fs.h:2270 [inline]
       mmap_region+0xdd0/0x1a98 mm/mmap.c:2763
       do_mmap+0xa00/0x1108 mm/mmap.c:1425
       vm_mmap_pgoff+0x1a4/0x2b4 mm/util.c:520
       ksys_mmap_pgoff+0x3c8/0x5b0 mm/mmap.c:1471
       __do_sys_mmap arch/arm64/kernel/sys.c:28 [inline]
       __se_sys_mmap arch/arm64/kernel/sys.c:21 [inline]
       __arm64_sys_mmap+0xf8/0x110 arch/arm64/kernel/sys.c:21
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
       do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:204
       el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

-> #0 (&mm->mmap_lock){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3090 [inline]
       check_prevs_add kernel/locking/lockdep.c:3209 [inline]
       validate_chain kernel/locking/lockdep.c:3825 [inline]
       __lock_acquire+0x3338/0x7680 kernel/locking/lockdep.c:5049
       lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5662
       __might_fault+0xc4/0x124 mm/memory.c:5851
       fault_in_readable+0x188/0x5f0 mm/gup.c:1891
       fault_in_iov_iter_readable+0xcc/0x22c lib/iov_iter.c:356
       generic_perform_write+0x1c8/0x55c mm/filemap.c:3835
       __generic_file_write_iter+0x168/0x388 mm/filemap.c:3973
       ntfs_file_write_iter+0x4d4/0x580 fs/ntfs3/file.c:1165
       call_write_iter include/linux/fs.h:2265 [inline]
       new_sync_write fs/read_write.c:491 [inline]
       vfs_write+0x610/0x91c fs/read_write.c:584
       ksys_write+0x15c/0x26c fs/read_write.c:637
       __do_sys_write fs/read_write.c:649 [inline]
       __se_sys_write fs/read_write.c:646 [inline]
       __arm64_sys_write+0x7c/0x90 fs/read_write.c:646
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
       do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:204
       el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sb->s_type->i_mutex_key#17);
                               lock(&mm->mmap_lock);
                               lock(&sb->s_type->i_mutex_key#17);
  lock(&mm->mmap_lock);

 *** DEADLOCK ***

3 locks held by syz-executor352/4289:
 #0: ffff0000d82cdc68 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x124/0x16c fs/file.c:1031
 #1: ffff0000da4e2460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x244/0x91c fs/read_write.c:580
 #2: ffff0000e5007240 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}, at: inode_trylock include/linux/fs.h:778 [inline]
 #2: ffff0000e5007240 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}, at: ntfs_file_write_iter+0x190/0x580 fs/ntfs3/file.c:1144

stack backtrace:
CPU: 1 PID: 4289 Comm: syz-executor352 Not tainted 6.1.116-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2048
 check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2170
 check_prev_add kernel/locking/lockdep.c:3090 [inline]
 check_prevs_add kernel/locking/lockdep.c:3209 [inline]
 validate_chain kernel/locking/lockdep.c:3825 [inline]
 __lock_acquire+0x3338/0x7680 kernel/locking/lockdep.c:5049
 lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5662
 __might_fault+0xc4/0x124 mm/memory.c:5851
 fault_in_readable+0x188/0x5f0 mm/gup.c:1891
 fault_in_iov_iter_readable+0xcc/0x22c lib/iov_iter.c:356
 generic_perform_write+0x1c8/0x55c mm/filemap.c:3835
 __generic_file_write_iter+0x168/0x388 mm/filemap.c:3973
 ntfs_file_write_iter+0x4d4/0x580 fs/ntfs3/file.c:1165
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x610/0x91c fs/read_write.c:584
 ksys_write+0x15c/0x26c fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __arm64_sys_write+0x7c/0x90 fs/read_write.c:646
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Crashes (256):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/09 15:33 linux-6.1.y d7039b844a1c 6b856513 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/07/09 03:52 linux-6.1.y 04d1ccaa9c28 4d9fdfa4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/06/26 09:51 linux-6.1.y 58485ff1a74f 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/06/16 17:21 linux-6.1.y 58485ff1a74f d1716036 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/06/02 02:07 linux-6.1.y da3c5173c55f 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/05/22 23:54 linux-6.1.y da3c5173c55f 0919b50b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/05/05 19:23 linux-6.1.y ac7079a42ea5 6ca47dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/04/28 22:25 linux-6.1.y 535ec20c5027 aeb6ec69 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/04/24 09:55 linux-6.1.y 420102835862 9882047a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/04/22 16:07 linux-6.1.y 420102835862 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/04/11 01:18 linux-6.1.y 420102835862 1ef3ab4d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/04/08 12:10 linux-6.1.y 3dfebb87d7eb a775275d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/04/04 12:39 linux-6.1.y 8e60a714ba3b 1c4febdb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/03/21 23:33 linux-6.1.y 344a09659766 c6512ef7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/03/20 22:29 linux-6.1.y 344a09659766 62330552 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/03/17 09:07 linux-6.1.y 344a09659766 948c34e4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/03/14 07:07 linux-6.1.y 344a09659766 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/03/13 11:26 linux-6.1.y 6ae7ac5c4251 44be8b44 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ntfs_file_write_iter
2025/06/25 12:55 linux-6.1.y 58485ff1a74f 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/06/13 11:24 linux-6.1.y 58485ff1a74f 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/06/11 23:47 linux-6.1.y 58485ff1a74f 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/06/10 23:58 linux-6.1.y 58485ff1a74f 5d7e17ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/06/10 14:16 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/06/09 04:44 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/06/04 18:04 linux-6.1.y 58485ff1a74f e565f08d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/06/04 00:50 linux-6.1.y da3c5173c55f a30356b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/06/04 00:49 linux-6.1.y da3c5173c55f a30356b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/05/14 12:19 linux-6.1.y 02b72ccb5f9d 7344edeb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/05/06 04:56 linux-6.1.y ac7079a42ea5 ae98e6b9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/05/04 08:11 linux-6.1.y b6736e03756f b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/05/02 18:51 linux-6.1.y b6736e03756f b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/04/30 23:05 linux-6.1.y 535ec20c5027 ce7952f4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/04/29 10:08 linux-6.1.y 535ec20c5027 aeb6ec69 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/04/26 13:45 linux-6.1.y 535ec20c5027 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/04/23 14:07 linux-6.1.y 420102835862 53a8b9bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/04/20 14:30 linux-6.1.y 420102835862 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/03/26 21:57 linux-6.1.y 344a09659766 20510e88 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/03/17 08:38 linux-6.1.y 344a09659766 948c34e4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/03/16 16:50 linux-6.1.y 344a09659766 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/03/16 12:45 linux-6.1.y 344a09659766 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/03/16 11:43 linux-6.1.y 344a09659766 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/03/16 02:04 linux-6.1.y 344a09659766 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/03/09 15:57 linux-6.1.y 6ae7ac5c4251 163f510d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/02/28 19:58 linux-6.1.y 3a8358583626 67cf5345 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/02/28 10:53 linux-6.1.y 3a8358583626 6a8fcbc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2025/02/28 08:21 linux-6.1.y 3a8358583626 6a8fcbc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
2024/08/03 11:07 linux-6.1.y 48d525b0e463 1786a2a8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ntfs_file_write_iter
* Struck through repros no longer work on HEAD.