[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
This bug was fixed in the package openssh - 1:7.6p1-4ubuntu0.7 --- openssh (1:7.6p1-4ubuntu0.7) bionic; urgency=medium * d/p/fix-connect-timeout-overflow.patch: prevent ConnectTimeout overflow. (LP: #1903516) [ Sergio Durigan Junior ] * d/p/lp1966591-upstream-preserve-group-world-read-permission-on-kno.patch: Preserve group/world read permissions on known_hosts. (LP: #1966591) -- Athos Ribeiro Wed, 30 Mar 2022 10:17:14 -0300 ** Changed in: openssh (Ubuntu Bionic) Status: Fix Committed => Fix Released -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: Fix Released Status in openssh source package in Focal: Fix Released Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: [Impact] When using "ssh-keygen -R" to remove a host from "known_hosts" the command changes permissions on the file. This can cause problems particularly when used on the global "known_hosts" file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non-root users suddenly fail to SSH and it's not immediately obvious why. [Test Plan] The problem happens on Bionic and Focal. $ lxc launch ubuntu-daily:focal openssh-bug1966591 $ lxc shell openssh-bug1966591 # ssh-keyscan github.com > test_known_hosts # chmod 644 test_known_hosts # ssh-keygen -R github.com -f test_known_hosts # stat test_known_hosts ... Access: (0600/-rw---) ... ... [Where problems could occur] The upstream patch is very simple and it is unlikely that it will cause any regressions. An indirect problem that could occur is that users might expect to see a more strict set of permissions on a "known_hosts" file after using "ssh-keygen -R", but arguably this is not defined behaviour and should not be relied upon. Of course, there is always a (very) small risk of introducing problems when rebuilding packages using newer versions of its dependencies (especially on Bionic, because it's older). [Original Description] When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
This bug was fixed in the package openssh - 1:8.2p1-4ubuntu0.5 --- openssh (1:8.2p1-4ubuntu0.5) focal; urgency=medium * d/p/fix-connect-timeout-overflow.patch: prevent ConnectTimeout overflow. (LP: #1903516) [ Sergio Durigan Junior ] * d/p/lp1966591-upstream-preserve-group-world-read-permission-on-kno.patch: Preserve group/world read permissions on known_hosts. (LP: #1966591) -- Athos Ribeiro Wed, 30 Mar 2022 10:03:15 -0300 ** Changed in: openssh (Ubuntu Focal) Status: Fix Committed => Fix Released -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: Fix Released Status in openssh source package in Focal: Fix Released Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: [Impact] When using "ssh-keygen -R" to remove a host from "known_hosts" the command changes permissions on the file. This can cause problems particularly when used on the global "known_hosts" file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non-root users suddenly fail to SSH and it's not immediately obvious why. [Test Plan] The problem happens on Bionic and Focal. $ lxc launch ubuntu-daily:focal openssh-bug1966591 $ lxc shell openssh-bug1966591 # ssh-keyscan github.com > test_known_hosts # chmod 644 test_known_hosts # ssh-keygen -R github.com -f test_known_hosts # stat test_known_hosts ... Access: (0600/-rw---) ... ... [Where problems could occur] The upstream patch is very simple and it is unlikely that it will cause any regressions. An indirect problem that could occur is that users might expect to see a more strict set of permissions on a "known_hosts" file after using "ssh-keygen -R", but arguably this is not defined behaviour and should not be relied upon. Of course, there is always a (very) small risk of introducing problems when rebuilding packages using newer versions of its dependencies (especially on Bionic, because it's older). [Original Description] When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
FWIW, I've also retriggered the tests marked as OLD_NEUTRAL. It should take a while until everything runs. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: Fix Committed Status in openssh source package in Focal: Fix Committed Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: [Impact] When using "ssh-keygen -R" to remove a host from "known_hosts" the command changes permissions on the file. This can cause problems particularly when used on the global "known_hosts" file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non-root users suddenly fail to SSH and it's not immediately obvious why. [Test Plan] The problem happens on Bionic and Focal. $ lxc launch ubuntu-daily:focal openssh-bug1966591 $ lxc shell openssh-bug1966591 # ssh-keyscan github.com > test_known_hosts # chmod 644 test_known_hosts # ssh-keygen -R github.com -f test_known_hosts # stat test_known_hosts ... Access: (0600/-rw---) ... ... [Where problems could occur] The upstream patch is very simple and it is unlikely that it will cause any regressions. An indirect problem that could occur is that users might expect to see a more strict set of permissions on a "known_hosts" file after using "ssh-keygen -R", but arguably this is not defined behaviour and should not be relied upon. Of course, there is always a (very) small risk of introducing problems when rebuilding packages using newer versions of its dependencies (especially on Bionic, because it's older). [Original Description] When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
The Impish failure passed with a retrigger, as expected. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: Fix Committed Status in openssh source package in Focal: Fix Committed Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: [Impact] When using "ssh-keygen -R" to remove a host from "known_hosts" the command changes permissions on the file. This can cause problems particularly when used on the global "known_hosts" file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non-root users suddenly fail to SSH and it's not immediately obvious why. [Test Plan] The problem happens on Bionic and Focal. $ lxc launch ubuntu-daily:focal openssh-bug1966591 $ lxc shell openssh-bug1966591 # ssh-keyscan github.com > test_known_hosts # chmod 644 test_known_hosts # ssh-keygen -R github.com -f test_known_hosts # stat test_known_hosts ... Access: (0600/-rw---) ... ... [Where problems could occur] The upstream patch is very simple and it is unlikely that it will cause any regressions. An indirect problem that could occur is that users might expect to see a more strict set of permissions on a "known_hosts" file after using "ssh-keygen -R", but arguably this is not defined behaviour and should not be relied upon. Of course, there is always a (very) small risk of introducing problems when rebuilding packages using newer versions of its dependencies (especially on Bionic, because it's older). [Original Description] When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
Sorry about that. There are not failures on Focal, but there were a bunch of old passes, so I've retriggered them. I'm investigating what's happening with the Impish one. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: Fix Committed Status in openssh source package in Focal: Fix Committed Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: [Impact] When using "ssh-keygen -R" to remove a host from "known_hosts" the command changes permissions on the file. This can cause problems particularly when used on the global "known_hosts" file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non-root users suddenly fail to SSH and it's not immediately obvious why. [Test Plan] The problem happens on Bionic and Focal. $ lxc launch ubuntu-daily:focal openssh-bug1966591 $ lxc shell openssh-bug1966591 # ssh-keyscan github.com > test_known_hosts # chmod 644 test_known_hosts # ssh-keygen -R github.com -f test_known_hosts # stat test_known_hosts ... Access: (0600/-rw---) ... ... [Where problems could occur] The upstream patch is very simple and it is unlikely that it will cause any regressions. An indirect problem that could occur is that users might expect to see a more strict set of permissions on a "known_hosts" file after using "ssh-keygen -R", but arguably this is not defined behaviour and should not be relied upon. Of course, there is always a (very) small risk of introducing problems when rebuilding packages using newer versions of its dependencies (especially on Bionic, because it's older). [Original Description] When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
Please investigate the gvfs autopkgtests failures for impish and focal as these are blocking the release of openssh for those releases and subsequently the release for bionic too. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: Fix Committed Status in openssh source package in Focal: Fix Committed Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: [Impact] When using "ssh-keygen -R" to remove a host from "known_hosts" the command changes permissions on the file. This can cause problems particularly when used on the global "known_hosts" file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non-root users suddenly fail to SSH and it's not immediately obvious why. [Test Plan] The problem happens on Bionic and Focal. $ lxc launch ubuntu-daily:focal openssh-bug1966591 $ lxc shell openssh-bug1966591 # ssh-keyscan github.com > test_known_hosts # chmod 644 test_known_hosts # ssh-keygen -R github.com -f test_known_hosts # stat test_known_hosts ... Access: (0600/-rw---) ... ... [Where problems could occur] The upstream patch is very simple and it is unlikely that it will cause any regressions. An indirect problem that could occur is that users might expect to see a more strict set of permissions on a "known_hosts" file after using "ssh-keygen -R", but arguably this is not defined behaviour and should not be relied upon. Of course, there is always a (very) small risk of introducing problems when rebuilding packages using newer versions of its dependencies (especially on Bionic, because it's older). [Original Description] When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
Verification for Focal: First, verifying that the bug manifests with the current package: # apt policy openssh-client openssh-client: Installed: 1:8.2p1-4ubuntu0.4 Candidate: 1:8.2p1-4ubuntu0.4 Version table: *** 1:8.2p1-4ubuntu0.4 500 500 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages 100 /var/lib/dpkg/status 1:8.2p1-4ubuntu0.2 500 500 http://security.ubuntu.com/ubuntu focal-security/main amd64 Packages 1:8.2p1-4 500 500 http://archive.ubuntu.com/ubuntu focal/main amd64 Packages # ssh-keygen -R github.com -f test_known_hosts # Host github.com found: line 1 # Host github.com found: line 2 # Host github.com found: line 3 test_known_hosts updated. Original contents retained as test_known_hosts.old # stat test_known_hosts | grep ^Access Access: (0600/-rw---) Uid: (0/root) Gid: (0/root) Access: 2022-04-13 21:54:40.698183232 + Now, enabling -proposed and verifying that the new package fixes the bug: # apt policy openssh-client openssh-client: Installed: 1:8.2p1-4ubuntu0.5 Candidate: 1:8.2p1-4ubuntu0.5 Version table: *** 1:8.2p1-4ubuntu0.5 500 500 http://archive.ubuntu.com/ubuntu focal-proposed/main amd64 Packages 100 /var/lib/dpkg/status 1:8.2p1-4ubuntu0.4 500 500 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages 1:8.2p1-4ubuntu0.2 500 500 http://security.ubuntu.com/ubuntu focal-security/main amd64 Packages 1:8.2p1-4 500 500 http://archive.ubuntu.com/ubuntu focal/main amd64 Packages # ssh-keygen -R github.com -f test_known_hosts # Host github.com found: line 1 # Host github.com found: line 2 # Host github.com found: line 3 test_known_hosts updated. Original contents retained as test_known_hosts.old # stat test_known_hosts | grep ^Access Access: (0644/-rw-r--r--) Uid: (0/root) Gid: (0/root) Access: 2022-04-13 21:57:25.676987718 + The bug has been fixed. ** Tags removed: server-todo verification-needed verification-needed-focal ** Tags added: verification-done-focal -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: Fix Committed Status in openssh source package in Focal: Fix Committed Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: [Impact] When using "ssh-keygen -R" to remove a host from "known_hosts" the command changes permissions on the file. This can cause problems particularly when used on the global "known_hosts" file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non-root users suddenly fail to SSH and it's not immediately obvious why. [Test Plan] The problem happens on Bionic and Focal. $ lxc launch ubuntu-daily:focal openssh-bug1966591 $ lxc shell openssh-bug1966591 # ssh-keyscan github.com > test_known_hosts # chmod 644 test_known_hosts # ssh-keygen -R github.com -f test_known_hosts # stat test_known_hosts ... Access: (0600/-rw---) ... ... [Where problems could occur] The upstream patch is very simple and it is unlikely that it will cause any regressions. An indirect problem that could occur is that users might expect to see a more strict set of permissions on a "known_hosts" file after using "ssh-keygen -R", but arguably this is not defined behaviour and should not be relied upon. Of course, there is always a (very) small risk of introducing problems when rebuilding packages using newer versions of its dependencies (especially on Bionic, because it's older). [Original Description] When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
Tested openssh-client/bionic-proposed,now 1:7.6p1-4ubuntu0.7 and confirmed that group's and others' read permissions are now preserved. Write and execute permissions are still removed, that is, a umask of 0133 seems to be applied. ** Tags removed: verification-needed-bionic ** Tags added: verification-done-bionic -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: Fix Committed Status in openssh source package in Focal: Fix Committed Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: [Impact] When using "ssh-keygen -R" to remove a host from "known_hosts" the command changes permissions on the file. This can cause problems particularly when used on the global "known_hosts" file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non-root users suddenly fail to SSH and it's not immediately obvious why. [Test Plan] The problem happens on Bionic and Focal. $ lxc launch ubuntu-daily:focal openssh-bug1966591 $ lxc shell openssh-bug1966591 # ssh-keyscan github.com > test_known_hosts # chmod 644 test_known_hosts # ssh-keygen -R github.com -f test_known_hosts # stat test_known_hosts ... Access: (0600/-rw---) ... ... [Where problems could occur] The upstream patch is very simple and it is unlikely that it will cause any regressions. An indirect problem that could occur is that users might expect to see a more strict set of permissions on a "known_hosts" file after using "ssh-keygen -R", but arguably this is not defined behaviour and should not be relied upon. Of course, there is always a (very) small risk of introducing problems when rebuilding packages using newer versions of its dependencies (especially on Bionic, because it's older). [Original Description] When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
Hello Evgeny, or anyone else affected, Accepted openssh into focal-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/openssh/1:8.2p1-4ubuntu0.5 in a few hours, and then in the -proposed repository. Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users. If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed- focal to verification-done-focal. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification- failed-focal. In either case, without details of your testing we will not be able to proceed. Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping! N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days. ** Changed in: openssh (Ubuntu Focal) Status: In Progress => Fix Committed ** Tags added: verification-needed verification-needed-focal ** Changed in: openssh (Ubuntu Bionic) Status: In Progress => Fix Committed ** Tags added: verification-needed-bionic -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: Fix Committed Status in openssh source package in Focal: Fix Committed Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: [Impact] When using "ssh-keygen -R" to remove a host from "known_hosts" the command changes permissions on the file. This can cause problems particularly when used on the global "known_hosts" file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non-root users suddenly fail to SSH and it's not immediately obvious why. [Test Plan] The problem happens on Bionic and Focal. $ lxc launch ubuntu-daily:focal openssh-bug1966591 $ lxc shell openssh-bug1966591 # ssh-keyscan github.com > test_known_hosts # chmod 644 test_known_hosts # ssh-keygen -R github.com -f test_known_hosts # stat test_known_hosts ... Access: (0600/-rw---) ... ... [Where problems could occur] The upstream patch is very simple and it is unlikely that it will cause any regressions. An indirect problem that could occur is that users might expect to see a more strict set of permissions on a "known_hosts" file after using "ssh-keygen -R", but arguably this is not defined behaviour and should not be relied upon. Of course, there is always a (very) small risk of introducing problems when rebuilding packages using newer versions of its dependencies (especially on Bionic, because it's older). [Original Description] When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
** Merge proposal linked: https://code.launchpad.net/~sergiodj/ubuntu/+source/openssh/+git/openssh/+merge/418099 ** Merge proposal linked: https://code.launchpad.net/~sergiodj/ubuntu/+source/openssh/+git/openssh/+merge/418100 ** Merge proposal linked: https://code.launchpad.net/~sergiodj/ubuntu/+source/openssh/+git/openssh/+merge/418101 ** Merge proposal linked: https://code.launchpad.net/~sergiodj/ubuntu/+source/openssh/+git/openssh/+merge/418102 -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: In Progress Status in openssh source package in Focal: In Progress Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: [Impact] When using "ssh-keygen -R" to remove a host from "known_hosts" the command changes permissions on the file. This can cause problems particularly when used on the global "known_hosts" file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non-root users suddenly fail to SSH and it's not immediately obvious why. [Test Plan] The problem happens on Bionic and Focal. $ lxc launch ubuntu-daily:focal openssh-bug1966591 $ lxc shell openssh-bug1966591 # ssh-keyscan github.com > test_known_hosts # chmod 644 test_known_hosts # ssh-keygen -R github.com -f test_known_hosts # stat test_known_hosts ... Access: (0600/-rw---) ... ... [Where problems could occur] The upstream patch is very simple and it is unlikely that it will cause any regressions. An indirect problem that could occur is that users might expect to see a more strict set of permissions on a "known_hosts" file after using "ssh-keygen -R", but arguably this is not defined behaviour and should not be relied upon. Of course, there is always a (very) small risk of introducing problems when rebuilding packages using newer versions of its dependencies (especially on Bionic, because it's older). [Original Description] When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
** Description changed: + [Impact] + + When using "ssh-keygen -R" to remove a host from "known_hosts" the + command changes permissions on the file. This can cause problems + particularly when used on the global "known_hosts" file + (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs + running non-interactively as non-root users suddenly fail to SSH and + it's not immediately obvious why. + + [Test Plan] + + The problem happens on Bionic and Focal. + + $ lxc launch ubuntu-daily:focal openssh-bug1966591 + $ lxc shell openssh-bug1966591 + # ssh-keyscan github.com > test_known_hosts + # chmod 644 test_known_hosts + # ssh-keygen -R github.com -f test_known_hosts + # stat test_known_hosts + ... + Access: (0600/-rw---) ... + ... + + [Where problems could occur] + + The upstream patch is very simple and it is unlikely that it will cause + any regressions. An indirect problem that could occur is that users + might expect to see a more strict set of permissions on a "known_hosts" + file after using "ssh-keygen -R", but arguably this is not defined + behaviour and should not be relied upon. Of course, there is always a + (very) small risk of introducing problems when rebuilding packages using + newer versions of its dependencies (especially on Bionic, because it's + older). + + [Original Description] + When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non-root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: - Installed: 1:7.6p1-4ubuntu0.6 + Installed: 1:7.6p1-4ubuntu0.6 -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: In Progress Status in openssh source package in Focal: In Progress Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: [Impact] When using "ssh-keygen -R" to remove a host from "known_hosts" the command changes permissions on the file. This can cause problems particularly when used on the global "known_hosts" file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non-root users suddenly fail to SSH and it's not immediately obvious why. [Test Plan] The problem happens on Bionic and Focal. $ lxc launch ubuntu-daily:focal openssh-bug1966591 $ lxc shell openssh-bug1966591 # ssh-keyscan github.com > test_known_hosts # chmod 644 test_known_hosts # ssh-keygen -R github.com -f test_known_hosts # stat test_known_hosts ... Access: (0600/-rw---) ... ... [Where problems could occur] The upstream patch is very simple and it is unlikely that it will cause any regressions. An indirect problem that could occur is that users might expect to see a more strict set of permissions on a "known_hosts" file after using "ssh-keygen -R", but arguably this is not defined behaviour and should not be relied upon. Of course, there is always a (very) small risk of introducing problems when rebuilding packages using newer versions of its dependencies (especially on Bionic, because it's older). [Original Description] When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to:
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
Thanks a lot! 0644 are really the important bits, so while the behavior is still "user-surprising" it shouldn't cause any practical problems for us. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: In Progress Status in openssh source package in Focal: In Progress Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
Thanks for the bug report Evgeny and for the initial investigation, Lena. The following commit "fixes" the issue: commit f2d84f1b3fa68d77c99238d4c645d0266fae2a74 Author: d...@openbsd.org AuthorDate: Wed May 13 09:55:57 2020 + Commit: Damien Miller CommitDate: Wed May 27 10:09:19 2020 +1000 I say "fixes" because it doesn't do exactly what Evgeny is asking in the bug description; that is, it doesn't make ssh-keygen preserve *all* of the permission bits. Instead, with the commit above applied we see that ssh-keygen in Focal/Bionic start behaving exactly like what we see in Impish/Jammy, and the group/all *read* permissions are preserved, but not the (e.g.) execute permission. We can see that on the output that Lena pasted. Either way, preserving the "read" permission bits for group/all and dropping everything else is done on purpose, as can be seen on this excerpt (from ssh-keygen.c:do_known_hosts): ... fchmod(fd, sb.st_mode & 0644); ... I have already backported & tested the patch on Bionic, and it works. I will start filing MPs tomorrow. ** Changed in: openssh (Ubuntu Bionic) Assignee: (unassigned) => Sergio Durigan Junior (sergiodj) ** Changed in: openssh (Ubuntu Focal) Assignee: (unassigned) => Sergio Durigan Junior (sergiodj) ** Changed in: openssh (Ubuntu Bionic) Status: Confirmed => Triaged ** Changed in: openssh (Ubuntu Bionic) Status: Triaged => In Progress ** Changed in: openssh (Ubuntu Focal) Status: Confirmed => In Progress -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: In Progress Status in openssh source package in Focal: In Progress Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
** Bug watch added: OpenSSH Portable Bugzilla #3146 https://bugzilla.mindrot.org/show_bug.cgi?id=3146 ** Also affects: openssh via https://bugzilla.mindrot.org/show_bug.cgi?id=3146 Importance: Unknown Status: Unknown -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in portable OpenSSH: Unknown Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: Confirmed Status in openssh source package in Focal: Confirmed Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1966591] Re: ssh-keygen -R changes known_hosts file permissions (mode)
Thank you for taking the time to report this bug while providing a good reproducer. I was able to reproduce in Focal and Bionic # ssh-keyscan github.com >test_known_hosts # ls -la test_known_hosts -rw-r--r-- 1 root root 656 Mar 28 14:24 test_known_hosts # ssh-keygen -R github.com -f test_known_hosts test_known_hosts updated. Original contents retained as test_known_hosts.old # ls -la test_known_hosts -rw--- 1 root root 0 Mar 28 14:25 test_known_hosts However in Jammy and Impish this is fixed: # ssh-keyscan github.com >test_known_hosts # ls -la test_known_hosts -rw-r--r-- 1 root root 656 Mar 28 14:30 test_known_hosts # ssh-keygen -R github.com -f test_known_hosts test_known_hosts updated. Original contents retained as test_known_hosts.old # ls -la test_known_hosts -rw-r--r-- 1 root root 0 Mar 28 14:31 test_known_hosts With this already being fixed in the newer releases it should just be a matter of finding the relevant commit and adding it to focal and bionic. Thanks ** Also affects: openssh (Ubuntu Impish) Importance: Undecided Status: New ** Also affects: openssh (Ubuntu Focal) Importance: Undecided Status: New ** Also affects: openssh (Ubuntu Jammy) Importance: Undecided Status: New ** Also affects: openssh (Ubuntu Bionic) Importance: Undecided Status: New ** Changed in: openssh (Ubuntu Impish) Status: New => Fix Released ** Changed in: openssh (Ubuntu Jammy) Status: New => Fix Released ** Changed in: openssh (Ubuntu Bionic) Status: New => Confirmed ** Changed in: openssh (Ubuntu Focal) Status: New => Confirmed ** Tags added: server-todo -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to openssh in Ubuntu. https://bugs.launchpad.net/bugs/1966591 Title: ssh-keygen -R changes known_hosts file permissions (mode) Status in openssh package in Ubuntu: Fix Released Status in openssh source package in Bionic: Confirmed Status in openssh source package in Focal: Confirmed Status in openssh source package in Impish: Fix Released Status in openssh source package in Jammy: Fix Released Bug description: When I use ssh-keygen -R to remove a host from known_hosts it changes permissions on the file. This causes problems particularly when used on the global known hosts file (/etc/ssh/ssh_known_hosts), because then only root can read it. Programs running non-interactively as non- root users suddenly fail to SSH and it's not immediately obvious why. To reproduce: $ ssh-keyscan github.com >test_known_hosts $ chmod 741 test_known_hosts $ ssh-keygen -R github.com -f test_known_hosts $ stat test_known_hosts ... Access: (0600/-rw---) ... Expected behavior: file permissions remain unchanged (mode 0741 in this example). $ lsb_release -rd Description: Ubuntu 18.04.6 LTS Release: 18.04 $ apt-cache policy openssh-client openssh-client: Installed: 1:7.6p1-4ubuntu0.6 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/openssh/+bug/1966591/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
