syzbot


possible deadlock in hfsplus_file_truncate

Status: upstream: reported C repro on 2022/11/26 08:07
Subsystems: hfs
[Documentation on labels]
Reported-by: syzbot+6030b3b1b9bf70e538c4@syzkaller.appspotmail.com
First crash: 374d, last: now
Cause bisection: failed (error log, bisect log)
  
Discussions (7)
Title Replies (including bot) Last reply
[syzbot] Monthly hfs report (Oct 2023) 0 (1) 2023/10/04 13:13
[syzbot] Monthly hfs report (Aug 2023) 0 (1) 2023/08/30 09:53
[syzbot] Monthly hfs report (Jul 2023) 0 (1) 2023/07/30 13:17
[syzbot] Monthly hfs report (Jun 2023) 0 (1) 2023/06/29 08:55
[syzbot] Monthly hfs report (May 2023) 0 (1) 2023/05/30 08:18
[syzbot] Monthly hfs report (Apr 2023) 0 (1) 2023/04/27 13:32
[syzbot] possible deadlock in hfsplus_file_truncate 0 (2) 2022/12/05 10:59
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 possible deadlock in hfsplus_file_truncate origin:upstream missing-backport C error 508 5h43m 268d 0/3 upstream: reported C repro on 2023/03/11 19:42
linux-6.1 possible deadlock in hfsplus_file_truncate missing-backport origin:lts-only C 470 4h44m 265d 0/3 upstream: reported C repro on 2023/03/15 11:18
linux-4.19 possible deadlock in hfsplus_file_truncate hfsplus C 165 273d 373d 0/1 upstream: reported C repro on 2022/11/27 09:20

Sample crash report:
loop0: detected capacity change from 0 to 1024
======================================================
WARNING: possible circular locking dependency detected
6.7.0-rc3-syzkaller-00284-g815fb87b7530 #0 Not tainted
------------------------------------------------------
syz-executor228/5436 is trying to acquire lock:
ffff88801f83a0b0 (&tree->tree_lock){+.+.}-{3:3}, at: hfsplus_file_truncate+0x811/0xb40 fs/hfsplus/extents.c:595

but task is already holding lock:
ffff88807baa5f88 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_truncate+0x2da/0xb40 fs/hfsplus/extents.c:576

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}:
       lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x136/0xd60 kernel/locking/mutex.c:747
       hfsplus_file_extend+0x21b/0x1b70 fs/hfsplus/extents.c:457
       hfsplus_bmap_reserve+0x105/0x4e0 fs/hfsplus/btree.c:358
       hfsplus_rename_cat+0x1d0/0x1050 fs/hfsplus/catalog.c:456
       hfsplus_rename+0x12e/0x1c0 fs/hfsplus/dir.c:552
       vfs_rename+0xaba/0xde0 fs/namei.c:4844
       do_renameat2+0xd5a/0x1390 fs/namei.c:4996
       __do_sys_rename fs/namei.c:5042 [inline]
       __se_sys_rename fs/namei.c:5040 [inline]
       __x64_sys_rename+0x86/0x90 fs/namei.c:5040
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x45/0x110 arch/x86/entry/common.c:82
       entry_SYSCALL_64_after_hwframe+0x63/0x6b

-> #0 (&tree->tree_lock){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain+0x1909/0x5ab0 kernel/locking/lockdep.c:3869
       __lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137
       lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x136/0xd60 kernel/locking/mutex.c:747
       hfsplus_file_truncate+0x811/0xb40 fs/hfsplus/extents.c:595
       hfsplus_setattr+0x1bd/0x260 fs/hfsplus/inode.c:269
       notify_change+0xb99/0xe60 fs/attr.c:499
       do_truncate+0x220/0x300 fs/open.c:66
       do_sys_ftruncate+0x2f3/0x390 fs/open.c:194
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x45/0x110 arch/x86/entry/common.c:82
       entry_SYSCALL_64_after_hwframe+0x63/0x6b

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&HFSPLUS_I(inode)->extents_lock);
                               lock(&tree->tree_lock);
                               lock(&HFSPLUS_I(inode)->extents_lock);
  lock(&tree->tree_lock);

 *** DEADLOCK ***

3 locks held by syz-executor228/5436:
 #0: ffff8880764f8418 (sb_writers#9){.+.+}-{0:0}, at: do_sys_ftruncate+0x258/0x390 fs/open.c:191
 #1: ffff88807baa6180 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline]
 #1: ffff88807baa6180 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: do_truncate+0x20c/0x300 fs/open.c:64
 #2: ffff88807baa5f88 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_truncate+0x2da/0xb40 fs/hfsplus/extents.c:576

stack backtrace:
CPU: 1 PID: 5436 Comm: syz-executor228 Not tainted 6.7.0-rc3-syzkaller-00284-g815fb87b7530 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x366/0x490 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain+0x1909/0x5ab0 kernel/locking/lockdep.c:3869
 __lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137
 lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x136/0xd60 kernel/locking/mutex.c:747
 hfsplus_file_truncate+0x811/0xb40 fs/hfsplus/extents.c:595
 hfsplus_setattr+0x1bd/0x260 fs/hfsplus/inode.c:269
 notify_change+0xb99/0xe60 fs/attr.c:499
 do_truncate+0x220/0x300 fs/open.c:66
 do_sys_ftruncate+0x2f3/0x390 fs/open.c:194
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x45/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7fe1a8ff0329
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 21 18 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffebc681748 EFLAGS: 00000246 ORIG_RAX: 000000000000004d
RAX: ffffffffffffffda RBX: 0031656c69662f2e RCX: 00007fe1a8ff0329
RDX: 0000000000000057 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 0073756c70736668 R08: 00000000200003c0 R09: 00007ffebc681780
R10: 0000000000000640 R11: 0000000000000246 R12: 00007ffebc68176c
R13: 000000000000014e R14: 431bde82d7b634db R15: 00007ffebc6817a0
 </TASK>

Crashes (6853):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/12/02 12:05 upstream 815fb87b7530 f819d6f7 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/11/07 19:45 upstream be3ca57cfb77 83211397 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-smack-root possible deadlock in hfsplus_file_truncate
2023/11/05 09:33 upstream aea6bf908d73 500bfdc4 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/10/25 01:47 upstream d88520ad73b7 17e6d526 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-smack-root possible deadlock in hfsplus_file_truncate
2023/10/19 06:57 upstream dd72f9c7e512 342b9c55 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-smack-root possible deadlock in hfsplus_file_truncate
2023/07/16 10:02 upstream 831fe284d827 35d9ecc5 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/07/13 13:58 upstream eb26cbb1a754 86081196 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-selinux-root possible deadlock in hfsplus_file_truncate
2023/07/03 11:21 upstream a901a3568fd2 bfc47836 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/06/30 08:12 upstream e8f75c0270d9 7b33cf8f .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/06/16 09:11 upstream 62d8779610bb f3921d4d .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/06/04 18:00 upstream e5282a7d8f6b a4ae4f42 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/06/02 16:25 upstream c43a6ff9f93f a4ae4f42 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/05/24 08:51 upstream 27e462c8fad4 4bce1a3e .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-smack-root possible deadlock in hfsplus_file_truncate
2023/01/01 13:11 upstream e4cf7c25bae5 ab32d508 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2022/12/05 10:58 upstream 0ba09b173387 e080de16 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/01/25 03:05 linux-next 691781f561e9 9dfcf09c .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci-upstream-linux-next-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/06/04 17:41 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci eb0f1697d729 a4ae4f42 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-gce-arm64 possible deadlock in hfsplus_file_truncate
2022/12/12 10:27 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci a5541c0811a0 67be1ae7 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-gce-arm64 possible deadlock in hfsplus_file_truncate
2023/12/04 03:15 upstream 33cc938e65a9 f819d6f7 .config console log report syz [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/05 10:57 upstream bee0e7762ad2 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/05 08:15 upstream bee0e7762ad2 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/05 07:00 upstream bee0e7762ad2 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/05 04:38 upstream bee0e7762ad2 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/05 02:52 upstream bee0e7762ad2 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in hfsplus_file_truncate
2023/12/05 02:19 upstream bee0e7762ad2 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in hfsplus_file_truncate
2023/12/05 00:53 upstream bee0e7762ad2 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in hfsplus_file_truncate
2023/12/04 23:24 upstream bee0e7762ad2 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/12/04 21:54 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/04 20:46 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/12/04 19:00 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/12/04 17:46 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/12/04 15:30 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/04 13:17 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/04 01:18 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root possible deadlock in hfsplus_file_truncate
2023/12/04 00:16 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/12/03 22:05 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root possible deadlock in hfsplus_file_truncate
2023/12/03 19:32 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/12/03 18:16 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/03 17:05 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in hfsplus_file_truncate
2023/12/03 15:55 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/12/03 14:35 upstream 33cc938e65a9 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/03 13:01 upstream 1b8af6552cb7 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/03 11:50 upstream 1b8af6552cb7 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/03 05:25 upstream 1b8af6552cb7 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root possible deadlock in hfsplus_file_truncate
2023/12/03 04:11 upstream 1b8af6552cb7 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root possible deadlock in hfsplus_file_truncate
2023/12/03 02:48 upstream 1b8af6552cb7 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/12/02 22:20 upstream 815fb87b7530 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/02 19:51 upstream 815fb87b7530 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/02 18:34 upstream 815fb87b7530 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/02 15:46 upstream 815fb87b7530 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/02 08:39 upstream 815fb87b7530 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/12/02 07:17 upstream 815fb87b7530 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/12/02 05:17 upstream 815fb87b7530 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/02 03:56 upstream 815fb87b7530 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/02 02:55 upstream 815fb87b7530 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/01 23:54 upstream 994d5c58e50e f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/12/01 20:11 upstream 994d5c58e50e f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/01 18:09 upstream 994d5c58e50e f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in hfsplus_file_truncate
2023/12/01 14:57 upstream 994d5c58e50e f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/01 13:47 upstream 994d5c58e50e f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/01 09:18 upstream e8f60209d6cf f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/12/05 05:41 upstream bee0e7762ad2 f819d6f7 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream possible deadlock in hfsplus_file_truncate
2023/12/03 01:21 upstream 1b8af6552cb7 f819d6f7 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream possible deadlock in hfsplus_file_truncate
2023/12/02 07:21 upstream 815fb87b7530 f819d6f7 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream possible deadlock in hfsplus_file_truncate
2023/11/23 19:36 upstream 9b6de136b5f0 5b429f39 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 possible deadlock in hfsplus_file_truncate
2022/11/26 07:12 upstream 08ad43d554ba f4470a7b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in hfsplus_file_truncate
2023/11/13 03:27 linux-next d173336e238b 6d6dbf8a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root possible deadlock in hfsplus_file_truncate
2023/12/03 09:12 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 2cc14f52aeb7 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in hfsplus_file_truncate
2023/12/02 14:26 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 2cc14f52aeb7 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in hfsplus_file_truncate
2023/12/01 11:13 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 2cc14f52aeb7 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in hfsplus_file_truncate
* Struck through repros no longer work on HEAD.