Can't cd to (unreachable)/: No such file or directory

[candrews]

This problem impacts version 2.11 (I did not have on any previous version).

Simply running needrestart yields this error:

Can't cd to (unreachable)/: No such file or directory===========================================================================                                                                                 ]

I suspect this problem was caused by 4e020cb

[candrews]

Confirmed that if I revert the change made in 4e020cb to Perl.pm that needrestart works again.

[liske]

I'm unable to reproduce this issue. Could you please provide the output of ls -la /proc/$PID for the affected process?

[candrews]

The error occurs at

needrestart/perl/lib/NeedRestart/Interp/Perl.pm

Line 163 in 4e020cb

$href = scan_deps(

I'm running sudo needrestart
$src is set to /usr/sbin/sqlgrey
$cwd is set to /home/candrews (if I run from other directories, I get the same error, so I don't think $cwd is important)
$pid is set to 15601

# ls -la /proc/15601
total 0
dr-xr-xr-x   9 sqlgrey sqlgrey 0 Jan 26 16:20 .
dr-xr-xr-x 314 root    root    0 Jan 22 17:34 ..
dr-xr-xr-x   2 sqlgrey sqlgrey 0 Jan 28 17:54 attr
-rw-r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 autogroup
-r--------   1 sqlgrey sqlgrey 0 Jan 28 17:54 auxv
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 28 05:20 cgroup
--w-------   1 sqlgrey sqlgrey 0 Jan 28 17:54 clear_refs
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 27 16:43 cmdline
-rw-r--r--   1 sqlgrey sqlgrey 0 Jan 28 05:20 comm
-rw-r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 coredump_filter
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 cpuset
lrwxrwxrwx   1 sqlgrey sqlgrey 0 Jan 28 17:38 cwd -> /
-r--------   1 sqlgrey sqlgrey 0 Jan 27 16:43 environ
lrwxrwxrwx   1 sqlgrey sqlgrey 0 Jan 27 16:43 exe -> /usr/bin/perl
dr-x------   2 sqlgrey sqlgrey 0 Jan 26 16:20 fd
dr-x------   2 sqlgrey sqlgrey 0 Jan 28 17:54 fdinfo
-rw-r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 gid_map
-r--------   1 sqlgrey sqlgrey 0 Jan 28 04:21 io
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 limits
-rw-r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 loginuid
dr-x------   2 sqlgrey sqlgrey 0 Jan 27 16:43 map_files
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 27 16:43 maps
-rw-------   1 sqlgrey sqlgrey 0 Jan 28 17:54 mem
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 mountinfo
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 mounts
-r--------   1 sqlgrey sqlgrey 0 Jan 28 17:54 mountstats
dr-xr-xr-x   5 sqlgrey sqlgrey 0 Jan 28 17:54 net
dr-x--x--x   2 sqlgrey sqlgrey 0 Jan 28 17:54 ns
-rw-r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 oom_adj
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 oom_score
-rw-r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 oom_score_adj
-r--------   1 sqlgrey sqlgrey 0 Jan 28 17:54 pagemap
-r--------   1 sqlgrey sqlgrey 0 Jan 28 17:54 personality
-rw-r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 projid_map
lrwxrwxrwx   1 sqlgrey sqlgrey 0 Jan 27 16:43 root -> /
-rw-r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 sched
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 schedstat
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 sessionid
-rw-r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 setgroups
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 smaps
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 26 16:20 stat
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 28 04:21 statm
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 27 16:43 status
-r--------   1 sqlgrey sqlgrey 0 Jan 28 17:54 syscall
dr-xr-xr-x   3 sqlgrey sqlgrey 0 Jan 28 17:54 task
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 timers
-rw-rw-rw-   1 sqlgrey sqlgrey 0 Jan 28 17:54 timerslack_ns
-rw-r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 uid_map
-r--r--r--   1 sqlgrey sqlgrey 0 Jan 28 17:54 wchan

I'm using "dev-perl/Module-ScanDeps" version 1.230.0
perl is v5.24.1

sqlgrey is run as a systemd service. Here's that information:

# systemctl cat sqlgrey
# /usr/lib/systemd/system/sqlgrey.service
[Unit]
Description=SQLgrey Postfix Grey-listing Policy service
After=network.target

[Service]
User=sqlgrey
Group=sqlgrey
ExecStart=/usr/sbin/sqlgrey
CapabilityBoundingSet=
PrivateTmp=yes
PrivateDevices=yes
ProtectSystem=full
ProtectHome=yes
NoNewPrivileges=yes
MemoryDenyWriteExecute=true
ProtectKernelModules=true
ProtectKernelTunables=true
ProtectControlGroups=true
RestrictRealtime=true

[Install]
WantedBy=multi-user.target

I'm using systemd 232.

[liske]

Maybe the issue is triggered by the ProtectSystem setting. Could you please try to run ls -la /proc/$PID/root (does it report an error?)?. Would it be possible for you to disable it temporary and check if the problem persists?

[candrews]

I removed ProtectSystem=full from sqlgrey.service and restarted it. needrestart still failed with the same error.

I ran ls -la /proc/$PID/root (with $PID being the pid I discovered using the approach in #55 (comment) ) and it shows a directory listing, no errors.

[stbuehler]

For starters I think there is a chdir($cwd) missing in NeedRestart/Interp/Perl.pm:143 to undo the current directory change before the return.

I have the same issue with sympa; with perl -MCarp::Always /usr/sbin/needrestart -v (after installing libcarp-always-perl) I get:

[Core] #10145 is a NeedRestart::Interp::Perl
/usr/share/perl5/NeedRestart/Interp/Perl.pm:107: chdir /proc/10145/root//var/lib/sympa/list_data
[Perl] #10145: source=/usr/lib/sympa/bin/archived.pl
Can't cd to (unreachable)/var/lib/sympa/list_data: No such file or directory
 at /usr/share/perl/5.24/File/Find.pm line 283.
        File::Find::_find_opt(HASH(0x562a04ecc118), "/usr/lib/x86_64-linux-gnu/perl/5.24/auto/POSIX") called at /usr/share/perl/5.24/File/Find.pm line 760
        File::Find::find(CODE(0x562a04ecbe90), "/usr/lib/x86_64-linux-gnu/perl/5.24/auto/POSIX") called at /usr/share/perl5/Module/ScanDeps.pm line 1177
        Module::ScanDeps::_glob_in_inc("auto/POSIX") called at /usr/share/perl5/Module/ScanDeps.pm line 1104
        Module::ScanDeps::add_deps("used_by", "archived.pl", "rv", HASH(0x562a04ecb5c0), "modules", ARRAY(0x562a04ecbd10), "skip", undef, ...) called at /usr/share/perl5/Module/ScanDeps.pm line 684
        Module::ScanDeps::scan_deps_static(HASH(0x562a050e4798)) called at /usr/share/perl5/Module/ScanDeps.pm line 614
        Module::ScanDeps::scan_deps("files", ARRAY(0x562a04ecb728), "recurse", 1) called at /usr/share/perl5/NeedRestart/Interp/Perl.pm line 165
        NeedRestart::Interp::Perl::files(NeedRestart::Interp::Perl=HASH(0x562a04eee548), 10145, HASH(0x562a04aa3410)) called at /usr/share/perl5/NeedRestart.pm line 171
        NeedRestart::needrestart_interp_check(1, 10145, "/usr/bin/perl", ARRAY(0x562a04e46280)) called at /usr/sbin/needrestart line 498

This is debian stretch amd64, with another print for the chdir debug line, and the fixed chdir before return.

[candrews]

@stbuehler can you please submit a pull request with your suggested change?

[stbuehler]

I guess you misunderstood me; the missing cwd restore was a bug, but not this bug - the output I showed with the backtrace of the problem was done with #70 already applied.

[renini]

Did this fix work for everyone? We currently experience this on lxc host running debian stable (stretch).
Tried needrestart 2.11-3 and 2.11-4

[nirgal]

I got the same issue after yesterday's Debian update (Version 9.6).

I have

command[needrestart]=sudo /usr/sbin/needrestart -p 2>&1

and a /etc/sudoers.d/needrestart file containing:

# Grant nrpe right to run needrestart as root
nagios     ALL=(root) NOPASSWD: /usr/sbin/needrestart -p

The error was:

/usr/lib/nagios/plugins/check_nrpe -H xxxxx.nirgal.com -c needrestart
Can't cd to (unreachable)/: No such file or directory

I did tried this fix (8311453) but it did not work.

Finally, I fixed it by switching back to system-v: aptitude install sysvinit-core.

[vdboor]

I can confirm this, needrestart is broken by the Debian 9.6 update. The same error occurs:

$ needrestart  -v
[main] eval /etc/needrestart/needrestart.conf
[main] needrestart v3.3
[main] running in root mode
[Core] Using UI 'NeedRestart::UI::stdio'...
[main] systemd detected
[main] #11763 uses deleted /lib/x86_64-linux-gnu/libsystemd.so.0.23.0
[main] #11763 is not a child
[Core] #18453 is a NeedRestart::Interp::Perl
[Perl] #18453: source=/usr/sbin/munin-node
Can't cd to (unreachable)/: No such file or directory

Stopping munin-node allowed needrestart to continue

[liske]

This issue seems to be related to #125.