syzbot


possible deadlock in map_mft_record (2)

Status: upstream: reported on 2024/09/14 09:25
Reported-by: syzbot+ba30c43520c2fdcee3a2@syzkaller.appspotmail.com
First crash: 227d, last: 75d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 possible deadlock in map_mft_record 13 394d 770d 0/3 auto-obsoleted due to no activity on 2024/07/09 13:58
upstream possible deadlock in map_mft_record ntfs3 C error done 845 455d 923d 25/28 fixed on 2024/03/20 11:33
linux-4.14 possible deadlock in map_mft_record ntfs C 5 803d 897d 0/1 upstream: reported C repro on 2022/11/15 01:41
upstream possible deadlock in map_mft_record (2) fs 1 389d 385d 0/28 auto-obsoleted due to no activity on 2024/07/04 04:55
linux-5.15 possible deadlock in map_mft_record 46 14d 774d 0/3 upstream: reported on 2023/03/17 18:38
linux-4.19 possible deadlock in map_mft_record ntfs C error 11 821d 933d 0/1 upstream: reported C repro on 2022/10/09 19:52

Sample crash report:
loop2: detected capacity change from 0 to 4096
ntfs: volume version 3.1.
======================================================
WARNING: possible circular locking dependency detected
6.1.128-syzkaller #0 Not tainted
------------------------------------------------------
syz.2.12922/2102 is trying to acquire lock:
ffff888070bf8190 (&ni->mrec_lock){+.+.}-{3:3}, at: map_mft_record+0x48/0x630 fs/ntfs/mft.c:154

but task is already holding lock:
ffff888070bf8100 (&rl->lock){++++}-{3:3}, at: ntfs_truncate+0x1e3/0x2860 fs/ntfs/inode.c:2378

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&rl->lock){++++}-{3:3}:
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
       down_read+0xad/0xa30 kernel/locking/rwsem.c:1520
       ntfs_read_block fs/ntfs/aops.c:248 [inline]
       ntfs_read_folio+0x14c9/0x29d0 fs/ntfs/aops.c:436
       filemap_read_folio+0x199/0x780 mm/filemap.c:2489
       do_read_cache_folio+0x2ee/0x810 mm/filemap.c:3626
       do_read_cache_page+0x32/0x220 mm/filemap.c:3668
       read_mapping_page include/linux/pagemap.h:791 [inline]
       ntfs_map_page fs/ntfs/aops.h:75 [inline]
       ntfs_sync_mft_mirror+0x258/0x1ad0 fs/ntfs/mft.c:480
       write_mft_record_nolock+0x13f6/0x18d0 fs/ntfs/mft.c:805
       write_mft_record+0x149/0x310 fs/ntfs/mft.h:95
       __ntfs_write_inode+0x6ff/0xbb0 fs/ntfs/inode.c:3050
       ntfs_commit_inode fs/ntfs/inode.h:300 [inline]
       ntfs_put_super+0x92/0xf80 fs/ntfs/super.c:2260
       generic_shutdown_super+0x130/0x340 fs/super.c:501
       kill_block_super+0x7a/0xe0 fs/super.c:1470
       deactivate_locked_super+0xa0/0x110 fs/super.c:332
       cleanup_mnt+0x490/0x520 fs/namespace.c:1186
       task_work_run+0x246/0x300 kernel/task_work.c:203
       resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
       exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
       exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
       __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
       syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
       do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&ni->mrec_lock){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3090 [inline]
       check_prevs_add kernel/locking/lockdep.c:3209 [inline]
       validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
       __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x132/0xd80 kernel/locking/mutex.c:747
       map_mft_record+0x48/0x630 fs/ntfs/mft.c:154
       ntfs_truncate+0x263/0x2860 fs/ntfs/inode.c:2383
       ntfs_truncate_vfs fs/ntfs/inode.c:2862 [inline]
       ntfs_setattr+0x2c7/0x3a0 fs/ntfs/inode.c:2914
       notify_change+0xce3/0xfc0 fs/attr.c:499
       do_truncate+0x21c/0x300 fs/open.c:65
       vfs_truncate+0x2dd/0x3a0 fs/open.c:111
       do_sys_truncate+0xda/0x190 fs/open.c:134
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&rl->lock);
                               lock(&ni->mrec_lock);
                               lock(&rl->lock);
  lock(&ni->mrec_lock);

 *** DEADLOCK ***

3 locks held by syz.2.12922/2102:
 #0: ffff8880520c8460 (sb_writers#30){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
 #1: ffff888070bf8470 (&sb->s_type->i_mutex_key#34){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff888070bf8470 (&sb->s_type->i_mutex_key#34){+.+.}-{3:3}, at: do_truncate+0x208/0x300 fs/open.c:63
 #2: ffff888070bf8100 (&rl->lock){++++}-{3:3}, at: ntfs_truncate+0x1e3/0x2860 fs/ntfs/inode.c:2378

stack backtrace:
CPU: 0 PID: 2102 Comm: syz.2.12922 Not tainted 6.1.128-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 check_noncircular+0x2fa/0x3b0 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+0x1661/0x5950 kernel/locking/lockdep.c:3825
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x132/0xd80 kernel/locking/mutex.c:747
 map_mft_record+0x48/0x630 fs/ntfs/mft.c:154
 ntfs_truncate+0x263/0x2860 fs/ntfs/inode.c:2383
 ntfs_truncate_vfs fs/ntfs/inode.c:2862 [inline]
 ntfs_setattr+0x2c7/0x3a0 fs/ntfs/inode.c:2914
 notify_change+0xce3/0xfc0 fs/attr.c:499
 do_truncate+0x21c/0x300 fs/open.c:65
 vfs_truncate+0x2dd/0x3a0 fs/open.c:111
 do_sys_truncate+0xda/0x190 fs/open.c:134
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f251518cde9
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:00007f25160b3038 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 00007f25153a5fa0 RCX: 00007f251518cde9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00004000000001c0
RBP: 00007f251520e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f25153a5fa0 R15: 00007fffe1d43938
 </TASK>
ntfs: (device loop2): ntfs_read_block(): Failed to read from inode 0x6, attribute type 0x80, vcn 0x0, offset 0x0 because its location on disk could not be determined even after retrying (error code -5).
ntfs: (device loop2): ntfs_read_block(): Failed to read from inode 0x6, attribute type 0x80, vcn 0x0, offset 0x800 because its location on disk could not be determined even after retrying (error code -5).
ntfs: (device loop2): __ntfs_bitmap_set_bits_in_run(): Failed to map first page (error -5), aborting.
ntfs: (device loop2): __ntfs_cluster_free(): Failed to clear first run (error -5), aborting.
ntfs: (device loop2): ntfs_truncate(): Failed to release cluster(s) (error code -5).  Unmount and run chkdsk to recover the lost cluster(s).

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/02/14 02:26 linux-6.1.y 0cbb5f65e52f d9a046cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in map_mft_record
2024/12/11 13:38 linux-6.1.y e4d90d63d385 ff949d25 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in map_mft_record
2024/09/14 09:24 linux-6.1.y 5f55cad62cc9 c7e35043 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in map_mft_record
* Struck through repros no longer work on HEAD.