[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
This bug was fixed in the package vsftpd - 3.0.5-0ubuntu1.1 --- vsftpd (3.0.5-0ubuntu1.1) jammy; urgency=medium * d/p/0078-0026-Prevent-hanging-in-SIGCHLD-handler.patch: avoid hang with pam_exec (LP: #2069324) -- Christian Ehrhardt Tue, 16 Jul 2024 09:52:02 +0200 ** Changed in: vsftpd (Ubuntu Jammy) Status: Fix Committed => Fix Released -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
This bug was fixed in the package vsftpd - 3.0.5-0ubuntu0.20.04.2 --- vsftpd (3.0.5-0ubuntu0.20.04.2) focal; urgency=medium * d/p/0076-0026-Prevent-hanging-in-SIGCHLD-handler.patch: avoid hang with pam_exec (LP: #2069324) -- Christian Ehrhardt Tue, 16 Jul 2024 09:50:23 +0200 ** Changed in: vsftpd (Ubuntu Focal) Status: Fix Committed => Fix Released -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Until we can reproduce on noble or later we can't act, marking it invalid on those tasks. ** Changed in: vsftpd (Ubuntu Noble) Status: Incomplete => Invalid ** Changed in: vsftpd (Ubuntu Oracular) Status: Incomplete => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
The automated test failure was testbed setup, not related to the case. A new run was enqueued and worked fine. => Bad run https://autopkgtest.ubuntu.com/results/autopkgtest-focal/focal/s390x/v/vsftpd/20240802_001540_a3c4c@/log.gz => good re-run https://autopkgtest.ubuntu.com/results/autopkgtest-focal/focal/s390x/v/vsftpd/20240805_055603_803c9@/log.gz Automation has thrown in a migration-reference/0 which also worked, so there is neither a continuous testbed issue nor an issue with vsftpd. Should be all good in the pending-sru overview once this new result was picked up. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Focal verification 1. Repro issue root@f:~# apt install lftp vsftpd Reading package lists... Done Building dependency tree Reading state information... Done The following additional packages will be installed: ssl-cert Suggested packages: openssl-blacklist The following NEW packages will be installed: lftp ssl-cert vsftpd 0 upgraded, 3 newly installed, 0 to remove and 0 not upgraded. Need to get 695 kB of archives. After this operation, 2098 kB of additional disk space will be used. Do you want to continue? [Y/n] Y Get:1 http://archive.ubuntu.com/ubuntu focal/main amd64 lftp amd64 4.8.4-2build3 [563 kB] Get:2 http://archive.ubuntu.com/ubuntu focal/main amd64 ssl-cert all 1.0.39 [17.0 kB] Get:3 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 vsftpd amd64 3.0.5-0ubuntu0.20.04.1 [115 kB] Fetched 695 kB in 1s (841 kB/s) Preconfiguring packages ... Selecting previously unselected package lftp. (Reading database ... 32221 files and directories currently installed.) Preparing to unpack .../lftp_4.8.4-2build3_amd64.deb ... Unpacking lftp (4.8.4-2build3) ... Selecting previously unselected package ssl-cert. Preparing to unpack .../ssl-cert_1.0.39_all.deb ... Unpacking ssl-cert (1.0.39) ... Selecting previously unselected package vsftpd. Preparing to unpack .../vsftpd_3.0.5-0ubuntu0.20.04.1_amd64.deb ... Unpacking vsftpd (3.0.5-0ubuntu0.20.04.1) ... Setting up lftp (4.8.4-2build3) ... Setting up ssl-cert (1.0.39) ... Setting up vsftpd (3.0.5-0ubuntu0.20.04.1) ... Created symlink /etc/systemd/system/multi-user.target.wants/vsftpd.service → /lib/systemd/system/vsftpd.service. Processing triggers for systemd (245.4-4ubuntu3.23) ... Processing triggers for man-db (2.9.1-1) ... Processing triggers for mime-support (3.64ubuntu1) ... root@f:~# sed -i.old '1 i\account optional pam_exec.so debug quiet /root/foo.sh\' /etc/pam.d/vsftpd root@f:~# cat > /root/foo.sh << EOF > #!/bin/bash > /bin/true > touch /tmp/brooks-was-here > /bin/true > EOF root@f:~# chmod +x /root/foo.sh root@f:~# sed -i -s -e 's/ssl_enable=NO/ssl_enable=YES/' /etc/vsftpd.conf root@f:~# systemctl restart vsftpd.service root@f:~# echo foobar > /home/ubuntu/egal root@f:~# echo 'ubuntu:ubuntu' | chpasswd root@f:~# lftp 127.0.0.1 lftp 127.0.0.1:~> set ftp:ssl-force true lftp 127.0.0.1:~> set ssl:verify-certificate false lftp 127.0.0.1:~> login ubuntu ubuntu lftp ubuntu@127.0.0.1:~> dir `ls' at 0 [Sending commands...] => hang 2. Install and verify fix root@f:~# cat # Enable Ubuntu proposed archive > deb http://archive.ubuntu.com/ubuntu/ $(lsb_release -cs)-proposed restricted > main multiverse universe > EOF root@f:~# apt update Hit:1 http://archive.ubuntu.com/ubuntu focal InRelease Hit:2 http://archive.ubuntu.com/ubuntu focal-updates InRelease Hit:3 http://archive.ubuntu.com/ubuntu focal-backports InRelease Get:4 http://archive.ubuntu.com/ubuntu focal-proposed InRelease [277 kB] Hit:5 http://security.ubuntu.com/ubuntu focal-security InRelease Get:6 http://archive.ubuntu.com/ubuntu focal-proposed/restricted amd64 Packages [474 kB] Get:7 http://archive.ubuntu.com/ubuntu focal-proposed/restricted Translation-en [65.0 kB] Get:8 http://archive.ubuntu.com/ubuntu focal-proposed/restricted amd64 c-n-f Metadata [420 B] Get:9 http://archive.ubuntu.com/ubuntu focal-proposed/main amd64 Packages [343 kB] Get:10 http://archive.ubuntu.com/ubuntu focal-proposed/main Translation-en [70.3 kB] Get:11 http://archive.ubuntu.com/ubuntu focal-proposed/main amd64 c-n-f Metadata [2156 B] Get:12 http://archive.ubuntu.com/ubuntu focal-proposed/multiverse amd64 Packages [7460 B] Get:13 http://archive.ubuntu.com/ubuntu focal-proposed/multiverse Translation-en [2348 B] Get:14 http://archive.ubuntu.com/ubuntu focal-proposed/multiverse amd64 c-n-f Metadata [312 B] Get:15 http://archive.ubuntu.com/ubuntu focal-proposed/universe amd64 Packages [58.4 kB] Get:16 http://archive.ubuntu.com/ubuntu focal-proposed/universe Translation-en [27.5 kB] Get:17 http://archive.ubuntu.com/ubuntu focal-proposed/universe amd64 c-n-f Metadata [2912 B] Fetched 1330 kB in 1s (1174 kB/s) Reading package lists... Done Building dependency tree Reading state information... Done 38 packages can be upgraded. Run 'apt list --upgradable' to see them. root@f:~# apt install lftp vsftpd Reading package lists... Done Building dependency tree Reading state information... Done lftp is already the newest version (4.8.4-2build3). The following packages will be upgraded: vsftpd 1 upgraded, 0 newly installed, 0 to remove and 37 not upgraded. Need to get 115 kB of archives. After this operation, 0 B of additional disk space will be used. Do you want to continue? [Y/n] Y Get:1 http://archive.ubuntu.com/ubuntu focal-proposed/main amd64 vsftpd amd64 3.0.5-0ubuntu0.20.04.2 [115 kB] Fetched 115 kB in 1s (229 kB/s) Preconfiguring packages ... (Reading dat
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Jammy verification 1. Repro issue root@j:~# apt install lftp vsftpd Reading package lists... Done Building dependency tree... Done Reading state information... Done The following additional packages will be installed: ssl-cert The following NEW packages will be installed: lftp ssl-cert vsftpd 0 upgraded, 3 newly installed, 0 to remove and 0 not upgraded. Need to get 860 kB of archives. After this operation, 2349 kB of additional disk space will be used. Do you want to continue? [Y/n] Y Get:1 http://archive.ubuntu.com/ubuntu jammy/main amd64 lftp amd64 4.9.2-1build1 [720 kB] Get:2 http://archive.ubuntu.com/ubuntu jammy/main amd64 ssl-cert all 1.1.2 [17.4 kB] Get:3 http://archive.ubuntu.com/ubuntu jammy/main amd64 vsftpd amd64 3.0.5-0ubuntu1 [123 kB] Fetched 860 kB in 1s (851 kB/s) Preconfiguring packages ... Selecting previously unselected package lftp. (Reading database ... 33953 files and directories currently installed.) Preparing to unpack .../lftp_4.9.2-1build1_amd64.deb ... Unpacking lftp (4.9.2-1build1) ... Selecting previously unselected package ssl-cert. Preparing to unpack .../ssl-cert_1.1.2_all.deb ... Unpacking ssl-cert (1.1.2) ... Selecting previously unselected package vsftpd. Preparing to unpack .../vsftpd_3.0.5-0ubuntu1_amd64.deb ... Unpacking vsftpd (3.0.5-0ubuntu1) ... Setting up lftp (4.9.2-1build1) ... Setting up ssl-cert (1.1.2) ... Setting up vsftpd (3.0.5-0ubuntu1) ... Created symlink /etc/systemd/system/multi-user.target.wants/vsftpd.service → /lib/systemd/system/vsftpd.service. Processing triggers for man-db (2.10.2-1) ... Scanning processes... No services need to be restarted. No containers need to be restarted. No user sessions are running outdated binaries. No VM guests are running outdated hypervisor (qemu) binaries on this host. root@j:~# sed -i.old '1 i\account optional pam_exec.so debug quiet /root/foo.sh\' /etc/pam.d/vsftpd root@j:~# cat > /root/foo.sh << EOF #!/bin/bash /bin/true touch /tmp/brooks-was-here /bin/true EOF root@j:~# chmod +x /root/foo.sh root@j:~# sed -i -s -e 's/ssl_enable=NO/ssl_enable=YES/' /etc/vsftpd.conf root@j:~# systemctl restart vsftpd.service root@j:~# echo foobar > /home/ubuntu/egal root@j:~# echo 'ubuntu:ubuntu' | chpasswd root@j:~# lftp 127.0.0.1 lftp 127.0.0.1:~> set ftp:ssl-force true lftp 127.0.0.1:~> set ssl:verify-certificate false lftp 127.0.0.1:~> login ubuntu ubuntu lftp ubuntu@127.0.0.1:~> dir `ls' at 0 [Sending commands...] => hang 2. Install and verify fix root@j:~# cat
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
It's weird that noble+ don't show the bug, but I agree that it's not worth updating there when we don't have a reported case, and our reproducer doesn't work there. ** Changed in: vsftpd (Ubuntu Jammy) Status: In Progress => Fix Committed ** Tags added: verification-needed verification-needed-jammy -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
MRs approved, uploaded for Focal and Jammy. Now waiting for the SRU team to find time for reviewing it in the -unapproved queue. ** Changed in: vsftpd (Ubuntu Focal) Status: Confirmed => In Progress ** Changed in: vsftpd (Ubuntu Jammy) Status: Confirmed => In Progress ** Changed in: vsftpd (Ubuntu Jammy) Assignee: (unassigned) => Christian Ehrhardt (paelzer) ** Changed in: vsftpd (Ubuntu Focal) Assignee: (unassigned) => Christian Ehrhardt (paelzer) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
** Description changed: [ Impact ] - * when running sub-processes on login through pam_exec a process + * User impact: under certain conditions using pam_exec the vsftp server +just hangs + + * Reason: when running sub-processes on login through pam_exec a process is spawned. That can confuse vsftp if that child ends triggering SIGCHLD but already been picked up by e.g. pam_exec.so itself. - * The fix uses waitpid over wait to be able to pass options. With that + * Fix: The fix uses waitpid over wait to be able to pass options. With that it sets WNOHANG in vsf_sysutil_wait except if it is explicitly called -to wait as done in common_do_login for the pre-login child. + to wait as done in common_do_login for the pre-login child. Therefore these other calls now allow it to "return immediately if -no child has exited" as defined for WNOHANG in [1] + no child has exited" as defined for WNOHANG in [1] [1]: https://manpages.ubuntu.com/manpages/noble/en/man2/wait.2.html [ Test Plan ] # install $ apt install lftp vsftpd # change config $ sed -i.old '1 i\account optional pam_exec.so debug quiet /root/foo.sh\' /etc/pam.d/vsftpd # script to run $ cat > /root/foo.sh << EOF #!/bin/bash /bin/true touch /tmp/brooks-was-here /bin/true EOF $ chmod +x /root/foo.sh # enable ssl $ sed -i -s -e 's/ssl_enable=NO/ssl_enable=YES/' /etc/vsftpd.conf $ systemctl restart vsftpd.service # Place a file there $ echo foobar > /home/ubuntu/egal # set test PW to ubuntu user echo 'ubuntu:ubuntu' | chpasswd # Using it with ftps (and ignore cert verification as it is the snakeoil cert) To verify the test config, if you run this in a second console you should see it calling the script as yo uact on the server. $ tail -f /var/log/auth.log ... 2024-07-16T07:30:37.966553+00:00 o vsftpd: pam_exec(vsftpd:account): Calling /root/foo.sh ... Good case (Noble / Oracular): root@n:~# lftp 127.0.0.1 lftp 127.0.0.1:~> set ftp:ssl-force true lftp 127.0.0.1:~> set ssl:verify-certificate false lftp 127.0.0.1:~> login ubuntu ubuntu lftp ubuntu@127.0.0.1:~> dir -rw-r--r-- 1 0 0 7 Jul 16 07:30 egal lftp ubuntu@127.0.0.1:~> get egal 7 bytes transferred lftp ubuntu@127.0.0.1:~> exit root@n:~# cat egal foobar Bad case (Focal and Jammy) root@j:~# lftp 127.0.0.1 lftp 127.0.0.1:~> set ftp:ssl-force true lftp 127.0.0.1:~> set ssl:verify-certificate false lftp 127.0.0.1:~> login ubuntu ubuntu lftp ubuntu@127.0.0.1:~> dir `ls' at 0 [Sending commands...] [ Where problems could occur ] * This changes signal handling for SIGCHLD. The code now returns cleanly if there was nobody to wait for, which formerly would have caused a the main process to die "Child died, so we'll do the same" That is intentionally changed for the condition of the child already being consumed. If there is a use case of the child leaving which was meant to terminate (unlikely, this is an unclean die call) it might no more happen now. [ Other Info ] * The code is the same (only no change rebuilds) still, this does not occur in Noble and Oracular. At least not with the current test setup. That is slightly disturbing. Also in the reproduction we've seen that it only occurred with FTPS, but that is not conceptually tied to the problem, it might only be yet another detail that changes the timing and size of the signal race window. Of course we can assume that it is just a race and the window is different there, but then should we not fix it? Or we can assume something else e.g. pam_exec has changed behavior to mask the issue and hence no vsftpd change is needed there. I think it is wasted to research this for ages, but it leaves some uncertainty. --- When you try to run a script with pam_exec.so on login vsftpd freezes with SIGCHLD. This was fixed in 2015 by redhat and never adopted to Debian/Ubunutu. See also: - https://bugzilla.redhat.com/show_bug.cgi?id=1198259 - https://git.centos.org/rpms/vsftpd/blob/54ac5fac29fcc1bb68f2e96e63ecfda655286ff8/f/SOURCES/0026-Prevent-hanging-in-SIGCHLD-handler.patch -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
** Description changed: [ Impact ] - * when running sub-processes on login through pam_exec a process -is spawned. That can confuse vsftp if that child ends triggering SIGCHLD but -already been picke dup by e.g. pam_exec.so itself. + * when running sub-processes on login through pam_exec a process + is spawned. That can confuse vsftp if that child ends triggering SIGCHLD but + already been picked up by e.g. pam_exec.so itself. - * The fix uses waitpid over wait to be able to pass options. With that -it sets WNOHANG when calling vsf_sysutil_wait is called from common_do_login -(as there pam_exec would run if configured). That allows it to -"return immediately if no child has exited" [1] + * The fix uses waitpid over wait to be able to pass options. With that + it sets WNOHANG in vsf_sysutil_wait except if it is explicitly called +to wait as done in common_do_login for the pre-login child. + Therefore these other calls now allow it to "return immediately if +no child has exited" as defined for WNOHANG in [1] [1]: https://manpages.ubuntu.com/manpages/noble/en/man2/wait.2.html [ Test Plan ] # install $ apt install lftp vsftpd # change config $ sed -i.old '1 i\account optional pam_exec.so debug quiet /root/foo.sh\' /etc/pam.d/vsftpd # script to run $ cat > /root/foo.sh << EOF #!/bin/bash /bin/true touch /tmp/brooks-was-here /bin/true EOF $ chmod +x /root/foo.sh # enable ssl $ sed -i -s -e 's/ssl_enable=NO/ssl_enable=YES/' /etc/vsftpd.conf $ systemctl restart vsftpd.service # Place a file there $ echo foobar > /home/ubuntu/egal # set test PW to ubuntu user echo 'ubuntu:ubuntu' | chpasswd # Using it with ftps (and ignore cert verification as it is the snakeoil cert) To verify the test config, if you run this in a second console you should see it calling the script as yo uact on the server. $ tail -f /var/log/auth.log ... 2024-07-16T07:30:37.966553+00:00 o vsftpd: pam_exec(vsftpd:account): Calling /root/foo.sh ... Good case (Noble / Oracular): root@n:~# lftp 127.0.0.1 lftp 127.0.0.1:~> set ftp:ssl-force true lftp 127.0.0.1:~> set ssl:verify-certificate false lftp 127.0.0.1:~> login ubuntu ubuntu lftp ubuntu@127.0.0.1:~> dir -rw-r--r-- 1 0 0 7 Jul 16 07:30 egal lftp ubuntu@127.0.0.1:~> get egal 7 bytes transferred lftp ubuntu@127.0.0.1:~> exit root@n:~# cat egal foobar Bad case (Focal and Jammy) root@j:~# lftp 127.0.0.1 lftp 127.0.0.1:~> set ftp:ssl-force true lftp 127.0.0.1:~> set ssl:verify-certificate false lftp 127.0.0.1:~> login ubuntu ubuntu lftp ubuntu@127.0.0.1:~> dir `ls' at 0 [Sending commands...] [ Where problems could occur ] * This changes signal handling for SIGCHLD. - The code now returns cleanly if there was nobody to wait for, which formerly - would have caused a the main process to die "Child died, so we'll do the same" - That is intentionally changed for the condition of the child already being - consumed. - If there is a use case of the child leaving which was meant to terminate - (unlikely, this is an unclean die call) it might no more happen now. + The code now returns cleanly if there was nobody to wait for, which formerly + would have caused a the main process to die "Child died, so we'll do the same" + That is intentionally changed for the condition of the child already being + consumed. + If there is a use case of the child leaving which was meant to terminate + (unlikely, this is an unclean die call) it might no more happen now. [ Other Info ] - * The code is the same (only no change rebuilds) still, this does not occur in - Noble and Oracular. At least not with the current test setup. That is slightly - disturbing. - Also in the reproduction we've seen that it only occurred with FTPS, but that - is not conceptually tied to the problem, it might only be yet another detail - that changes the timing and size of the signal race window. - Of course we can assume that it is just a race and the window is - different there, but then should we not fix it? Or we can assume something - else e.g. pam_exec has changed behavior to mask the issue and hence no vsftpd - change is needed there. I think it is wasted to research this for ages, but - it leaves some uncertainty. - + * The code is the same (only no change rebuilds) still, this does not occur in + Noble and Oracular. At least not with the current test setup. That is slightly + disturbing. + Also in the reproduction we've seen that it only occurred with FTPS, but that + is not conceptually tied to the problem, it might only be yet another detail + that changes the timing and size of the signal race window. + Of course we can assume that it is just a race and the window is + different there, but then should we not fix it? Or we can assume something + else e.g. pam_exec has cha
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
** Description changed: + [ Impact ] + + * when running sub-processes on login through pam_exec a process +is spawned. That can confuse vsftp if that child ends triggering SIGCHLD but +already been picke dup by e.g. pam_exec.so itself. + + * The fix uses waitpid over wait to be able to pass options. With that +it sets WNOHANG when calling vsf_sysutil_wait is called from common_do_login +(as there pam_exec would run if configured). That allows it to +"return immediately if no child has exited" [1] + + [1]: https://manpages.ubuntu.com/manpages/noble/en/man2/wait.2.html + + [ Test Plan ] + + # install + $ apt install lftp vsftpd + # change config + $ sed -i.old '1 i\account optional pam_exec.so debug quiet /root/foo.sh\' /etc/pam.d/vsftpd + # script to run + $ cat > /root/foo.sh << EOF + #!/bin/bash + /bin/true + touch /tmp/brooks-was-here + /bin/true + EOF + $ chmod +x /root/foo.sh + # enable ssl + $ sed -i -s -e 's/ssl_enable=NO/ssl_enable=YES/' /etc/vsftpd.conf + $ systemctl restart vsftpd.service + # Place a file there + $ echo foobar > /home/ubuntu/egal + # set test PW to ubuntu user + echo 'ubuntu:ubuntu' | chpasswd + + # Using it with ftps (and ignore cert verification as it is the snakeoil + cert) + + To verify the test config, if you run this in a second console you should see it calling the script as yo uact on the server. + $ tail -f /var/log/auth.log + ... + 2024-07-16T07:30:37.966553+00:00 o vsftpd: pam_exec(vsftpd:account): Calling /root/foo.sh ... + + Good case (Noble / Oracular): + + root@n:~# lftp 127.0.0.1 + lftp 127.0.0.1:~> set ftp:ssl-force true + lftp 127.0.0.1:~> set ssl:verify-certificate false + lftp 127.0.0.1:~> login ubuntu ubuntu + lftp ubuntu@127.0.0.1:~> dir + -rw-r--r-- 1 0 0 7 Jul 16 07:30 egal + lftp ubuntu@127.0.0.1:~> get egal + 7 bytes transferred + lftp ubuntu@127.0.0.1:~> + exit + root@n:~# cat egal + foobar + + Bad case (Focal and Jammy) + root@j:~# lftp 127.0.0.1 + lftp 127.0.0.1:~> set ftp:ssl-force true + lftp 127.0.0.1:~> set ssl:verify-certificate false + lftp 127.0.0.1:~> login ubuntu ubuntu + lftp ubuntu@127.0.0.1:~> dir + `ls' at 0 [Sending commands...] + + [ Where problems could occur ] + + * This changes signal handling for SIGCHLD. + The code now returns cleanly if there was nobody to wait for, which formerly + would have caused a the main process to die "Child died, so we'll do the same" + That is intentionally changed for the condition of the child already being + consumed. + If there is a use case of the child leaving which was meant to terminate + (unlikely, this is an unclean die call) it might no more happen now. + + [ Other Info ] + + * The code is the same (only no change rebuilds) still, this does not occur in + Noble and Oracular. At least not with the current test setup. That is slightly + disturbing. + Also in the reproduction we've seen that it only occurred with FTPS, but that + is not conceptually tied to the problem, it might only be yet another detail + that changes the timing and size of the signal race window. + Of course we can assume that it is just a race and the window is + different there, but then should we not fix it? Or we can assume something + else e.g. pam_exec has changed behavior to mask the issue and hence no vsftpd + change is needed there. I think it is wasted to research this for ages, but + it leaves some uncertainty. + + + --- + When you try to run a script with pam_exec.so on login vsftpd freezes with SIGCHLD. This was fixed in 2015 by redhat and never adopted to Debian/Ubunutu. See also: - https://bugzilla.redhat.com/show_bug.cgi?id=1198259 - https://git.centos.org/rpms/vsftpd/blob/54ac5fac29fcc1bb68f2e96e63ecfda655286ff8/f/SOURCES/0026-Prevent-hanging-in-SIGCHLD-handler.patch -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
** Merge proposal linked: https://code.launchpad.net/~paelzer/ubuntu/+source/vsftpd/+git/vsftpd/+merge/469466 ** Merge proposal linked: https://code.launchpad.net/~paelzer/ubuntu/+source/vsftpd/+git/vsftpd/+merge/469467 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
I was double checking this on other releases and got the hang on focal. I could indeed only trigger this with FTPS on focal, but AFAICS the same config as on Oracular. That motivated me, so I tried fresh F,J,N,O systems which in theory should all be the same but obviously behave different. And I found it is not affecting Noble and higher. That is weird in itself, as there the only difference is that they got two no change rebuilds (for a CVE and for libssl3t64) I was updating the steps to recreate as I used them for this. For >=Noble this either really is no issue due to yet unknown reasons, or on >Noble we need adapted test steps that would trigger it there. # install $ apt install lftp vsftpd # change config $ sed -i.old '1 i\account optionalpam_exec.so debug quiet /root/foo.sh\' /etc/pam.d/vsftpd # script to run $ cat > /root/foo.sh << EOF #!/bin/bash /bin/true touch /tmp/brooks-was-here /bin/true EOF $ chmod +x /root/foo.sh # enable ssl $ sed -i -s -e 's/ssl_enable=NO/ssl_enable=YES/' /etc/vsftpd.conf $ systemctl restart vsftpd.service # Place a file there $ echo foobar > /home/ubuntu/egal # set test PW to ubuntu user echo 'ubuntu:ubuntu' | chpasswd # Using it with ftps (and ignore cert verification as it is the snakeoil cert) To verify the test config, if you run this in a second console you should see it calling the script as yo uact on the server. $ tail -f /var/log/auth.log ... 2024-07-16T07:30:37.966553+00:00 o vsftpd: pam_exec(vsftpd:account): Calling /root/foo.sh ... Good case (Noble / Oracular): root@n:~# lftp 127.0.0.1 lftp 127.0.0.1:~> set ftp:ssl-force true lftp 127.0.0.1:~> set ssl:verify-certificate false lftp 127.0.0.1:~> login ubuntu ubuntu lftp ubuntu@127.0.0.1:~> dir -rw-r--r--1 00 7 Jul 16 07:30 egal lftp ubuntu@127.0.0.1:~> get egal 7 bytes transferred lftp ubuntu@127.0.0.1:~> exit root@n:~# cat egal foobar Bad case (Focal and Jammy) root@j:~# lftp 127.0.0.1 lftp 127.0.0.1:~> set ftp:ssl-force true lftp 127.0.0.1:~> set ssl:verify-certificate false lftp 127.0.0.1:~> login ubuntu ubuntu lftp ubuntu@127.0.0.1:~> dir `ls' at 0 [Sending commands...] ^^ here it hangs ** Also affects: vsftpd (Ubuntu Jammy) Importance: Undecided Status: New ** Also affects: vsftpd (Ubuntu Focal) Importance: Undecided Status: New ** Also affects: vsftpd (Ubuntu Noble) Importance: Undecided Status: New ** Also affects: vsftpd (Ubuntu Oracular) Importance: Undecided Status: Incomplete ** Changed in: vsftpd (Ubuntu Focal) Status: New => Confirmed ** Changed in: vsftpd (Ubuntu Jammy) Status: New => Confirmed ** Changed in: vsftpd (Ubuntu Noble) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Thanks Markus #1 trying with this now: account optionalpam_exec.so debug quiet /root/foo.sh And $ cat /root/foo.sh #!/bin/bash /bin/true touch /tmp/brooks-was-here /bin/true By default vsftp is configured for the snakeoil certificate to get started easily, but with ssl disabled. So enable it and restart. $ sed -i -s -e 's/ssl_enable=NO/ssl_enable=YES/' /etc/vsftpd.conf $ sudo systemctl restart vsftpd.service # Using it with ftps (and ignore cert verification as it is the snakeoil cert) root@o:~# lftp 127.0.0.1 lftp 127.0.0.1:~> set ftp:ssl-force true lftp 127.0.0.1:~> set ssl:verify-certificate false lftp 127.0.0.1:~> login ubuntu ubuntu lftp ubuntu@127.0.0.1:~> dir -rw-r--r--1 00 7 Jul 12 06:59 egal lftp ubuntu@127.0.0.1:~> get egal 7 bytes transferred lftp ubuntu@127.0.0.1:~> exit root@o:~# cat egal foobar root@o:~# ll /tmp/brooks-was-here -rw--- 1 root root 0 Jul 15 12:04 /tmp/brooks-was-here root@o:~# date Mon Jul 15 12:04:32 UTC 2024 I checked ftps was enabled e.g. a dir without it was not working: 530 Non-anonymous sessions must use encryption. Sadly that means it still works fine. We still need more from you about what is needed to trigger this hang :-/ -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
Re: [Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Hello, I acutally run a shell script /root/foo.sh which runs several commands. Maybe that is a difference. And I only use FTPS to connect. Regards, Markus Am 12.07.24 um 09:33 schrieb Christian Ehrhardt : > Hi, > first of all thanks for all the prep work. > The patch LGTM and I agree we should add it. > I was happy to see the suggestions on how to reproduce, but while writing it > out in more detail could not reproduce the hang. The following are the steps > I drafted to an SRU templates "how to test and verify" steps. But the hang > does not occur. Could you have a look where my steps diverge from what you > had in mind? > > > # Install ftp server > $ sudo apt install vsftpd > > # set a user with password, I use ubuntu:ubuntu in the examples here > $ passwd ubuntu > > # add testfile to the users home dir > $ echo foobar > /home/ubuntu/egal > > # Check with FTP if the normal setup works > root@o:~# ftp 127.0.0.1 > Connected to 127.0.0.1. > 220 (vsFTPd 3.0.5) > Name (127.0.0.1:root): ubuntu > 331 Please specify the password. > Password: > 230 Login successful. > Remote system type is UNIX. > Using binary mode to transfer files. > ftp> dir > 229 Entering Extended Passive Mode (|||47570|) > 150 Here comes the directory listing. > -rw-r--r--1 00 7 Jul 12 06:59 egal > 226 Directory send OK. > ftp> get egal > local: egal remote: egal > 229 Entering Extended Passive Mode (|||21047|) > 150 Opening BINARY mode data connection for egal (7 bytes). > 100% > |**| > 7 45.87 KiB/s00:00 ETA > 226 Transfer complete. > 7 bytes received in 00:00 (8.49 KiB/s) > ftp> ^D > 221 Goodbye. > root@o:~# cat egal > foobar > root@o:~# rm egal > > > # Now set up the failure condition > #1 add a few exec commands on pam > $ echo "account optionalpam_exec.so debug quiet /bin/true" | sudo > tee -a /etc/pam.d/vsftpd > > # Restart server to be sure to pick up everything > $ sudo systemctl restart vsftpd.service > > # Log in again to see the hang > $ ftp 127.0.0.1 > > ^^ but this does not fall into the hang, I can get the file and quit > normally. > > It is not that the setup is totally useless, in /var/log/auth.log I see on > the login > 2024-07-12T07:27:01.030634+00:00 o vsftpd: pam_exec(vsftpd:account): Calling > /bin/true ... > > > Do you have an advice what you do different to reproduce the issue? > > > P.S. along evaluating this I found many more changes we should apply to our > ftp servers. Not all suitable for SRUs, but going forward I want to still > improve them. To find the required time for that effort I internally filed > SD-1755 to not fall through the cracks forever. > > ** Changed in: vsftpd (Ubuntu) > Status: Triaged => Incomplete > -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Hi, first of all thanks for all the prep work. The patch LGTM and I agree we should add it. I was happy to see the suggestions on how to reproduce, but while writing it out in more detail could not reproduce the hang. The following are the steps I drafted to an SRU templates "how to test and verify" steps. But the hang does not occur. Could you have a look where my steps diverge from what you had in mind? # Install ftp server $ sudo apt install vsftpd # set a user with password, I use ubuntu:ubuntu in the examples here $ passwd ubuntu # add testfile to the users home dir $ echo foobar > /home/ubuntu/egal # Check with FTP if the normal setup works root@o:~# ftp 127.0.0.1 Connected to 127.0.0.1. 220 (vsFTPd 3.0.5) Name (127.0.0.1:root): ubuntu 331 Please specify the password. Password: 230 Login successful. Remote system type is UNIX. Using binary mode to transfer files. ftp> dir 229 Entering Extended Passive Mode (|||47570|) 150 Here comes the directory listing. -rw-r--r--1 00 7 Jul 12 06:59 egal 226 Directory send OK. ftp> get egal local: egal remote: egal 229 Entering Extended Passive Mode (|||21047|) 150 Opening BINARY mode data connection for egal (7 bytes). 100% |**| 7 45.87 KiB/s00:00 ETA 226 Transfer complete. 7 bytes received in 00:00 (8.49 KiB/s) ftp> ^D 221 Goodbye. root@o:~# cat egal foobar root@o:~# rm egal # Now set up the failure condition #1 add a few exec commands on pam $ echo "account optionalpam_exec.so debug quiet /bin/true" | sudo tee -a /etc/pam.d/vsftpd # Restart server to be sure to pick up everything $ sudo systemctl restart vsftpd.service # Log in again to see the hang $ ftp 127.0.0.1 ^^ but this does not fall into the hang, I can get the file and quit normally. It is not that the setup is totally useless, in /var/log/auth.log I see on the login 2024-07-12T07:27:01.030634+00:00 o vsftpd: pam_exec(vsftpd:account): Calling /bin/true ... Do you have an advice what you do different to reproduce the issue? P.S. along evaluating this I found many more changes we should apply to our ftp servers. Not all suitable for SRUs, but going forward I want to still improve them. To find the required time for that effort I internally filed SD-1755 to not fall through the cracks forever. ** Changed in: vsftpd (Ubuntu) Status: Triaged => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
Re: [Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Hello, reproduction is quite simple. Just add a pam_exec.so to PAM-config to run a small script. "exit 0" might do it. Or even simpler: accountoptional pam_exec.so debug quiet /bin/true Without the Patch vsftp hangs after a successful login. With the patch it continues running. Regards, Markus Am 10.07.24 um 06:10 schrieb Mitchell Dzurick: > Thank you for your time in attempting to install the package Markus. > > I agree with Paride in > https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/comments/8, > we should go ahead and implement this fix on our side. > > I'll attempt a quick repro tomorrow, but I'm pretty booked so if it > takes substantial time then I'll defer the reproduction and validation > for someone else. If repro is easy, I'll go ahead and stage the change > back to Focal. > -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Thank you for your time in attempting to install the package Markus. I agree with Paride in https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/comments/8, we should go ahead and implement this fix on our side. I'll attempt a quick repro tomorrow, but I'm pretty booked so if it takes substantial time then I'll defer the reproduction and validation for someone else. If repro is easy, I'll go ahead and stage the change back to Focal. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
** Changed in: vsftpd (Debian) Status: Unknown => New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
Re: [Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Sorry, I have no oracular to install the package. Only debian bookworm where it is not installable due to missing dependencies. I only uses the ubuntu sources to build my own patched version for debian. Am 03.07.24 um 06:14 schrieb Bryce Harrington: > Hi Markus - looks like Mitchell's PPA build succeeded. Have you had a > chance to install it on your server and test that it isn't showing the > crash? > -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Launchpad has imported 2 comments from the remote bug at https://bugzilla.redhat.com/show_bug.cgi?id=1198259. If you reply to an imported comment from within Launchpad, your comment will be sent to the remote bug automatically. Read more about Launchpad's inter-bugtracker facilities at https://help.launchpad.net/InterBugTracking. On 2015-03-03T16:38:32+00:00 dapospis wrote: The issue seems to appear also on RHEL7. +++ This bug was initially created as a clone of Bug #1092877 +++ Description of problem: The vsftpd hangs when the pam_exec.so is added to the /etc/pam.d/vsftpd. - ... ... sessioninclude password-auth sessionoptional pam_exec.so /bin/echo - Version-Release number of selected component (if applicable): vsftpd-3.0.2-9.el7 How reproducible: always Steps to Reproduce: 1. add pam_exec.so calling echo to /etc/pam.d/vsftpd 2. add session_support=YES to /etc/vsftpd/vsftpd.conf 3. restart vsftpd 4. connect with a client to the vsftpd 5. login and send e.g. ls command Actual results: The vsftpd hangs in SIGCHLD handler Expected results: The vsftpd will work as intended. Reply at: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/comments/0 On 2015-11-19T14:48:56+00:00 errata-xmlrpc wrote: Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://rhn.redhat.com/errata/RHEA-2015-2446.html Reply at: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/comments/1 ** Changed in: vsftpd (Fedora) Status: Unknown => Fix Released ** Changed in: vsftpd (Fedora) Importance: Unknown => High -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Hi Markus - looks like Mitchell's PPA build succeeded. Have you had a chance to install it on your server and test that it isn't showing the crash? -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
** Bug watch added: Red Hat Bugzilla #1198259 https://bugzilla.redhat.com/show_bug.cgi?id=1198259 ** Also affects: vsftpd (Fedora) via https://bugzilla.redhat.com/show_bug.cgi?id=1198259 Importance: Unknown Status: Unknown ** Also affects: vsftpd (Debian) via https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=952421 Importance: Unknown Status: Unknown -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Just kicked off a build at [0]. [0] - https://launchpad.net/~mitchdz/+archive/ubuntu/lp2069324-vsftpd- sigchld -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Thanks Markus, I'll make a PPA for that right now. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
Re: [Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
When it is needed I can try to install it on my server. Am 21.06.24 um 07:33 schrieb Mitchell Dzurick: > Markus, if we prepare a package with the patch, would you be willing to > help out testing the patch? > -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Markus, if we prepare a package with the patch, would you be willing to help out testing the patch? -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Looks like upstream development is *very* slow, and I could not find an issue tracker or a public vcs repo. Given that we have Ubuntu delta already (we're already ahead of Debian, which is still packaging 3.0.3), I believe it makes sense to add the patch to the Ubuntu package. ** Tags added: server-todo -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
** Bug watch added: Debian Bug tracker #952421 https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=952421 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
Re: [Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Well, there is a bug report from 2020 about the problem: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=952421 Am 18.06.24 um 21:01 schrieb Mitchell Dzurick: > Markus, would you mind making a bug report upstream to see if this could > be included? > -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Markus, would you mind making a bug report upstream to see if this could be included? -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
Re: [Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Hello, actually I am running "bookworm" and noticed that the packet is quite abandoned so I looked at the Ubuntu repository which had a newer release of vsftpd but also quite old. I build the ubuntu package on debian bookworm an noticed the same error. Then I rebuilt the same package with the attached patch applied and now it is working as expected. My custom script is run by pam_exec.so on login as it was intended. It would be great to see it applied upstream in Ubunutu and Debian as well. Just add a line to /etc/pam.d/vsftpd like this: accountoptional pam_exec.so debug quiet /root/my_script.sh And simply run "logger test" inside. Without the patch the vsftpd hangs as soon as someone logs in. Kind Regards, Markus Am 15.06.24 um 02:50 schrieb Mitchell Dzurick: > Markus, if I were to create a PPA with this patch applied, would you be > willing to help test that out? > > ** Changed in: vsftpd (Ubuntu) > Status: New => Triaged > -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Markus, if I were to create a PPA with this patch applied, would you be willing to help test that out? ** Changed in: vsftpd (Ubuntu) Status: New => Triaged -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
Thank you for taking the time to make this bug report Markus! -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
[Bug 2069324] Re: vsftpd hangs with SIGCHLD when pam_exec.so is used
What version of Ubuntu are you seeing this bug on? Unfortunately upstream/debian has been pretty dormant for a while, in-fact we are ahead of debian right now, so it may make sense to apply this patch. Unfortunately it looks like even upstream does not have this patch applied. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2069324 Title: vsftpd hangs with SIGCHLD when pam_exec.so is used To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/vsftpd/+bug/2069324/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
