On git://anongit.mindrot.org/openssh.git With bisect helper: $cat ../test-ssh.sh #!/bin/bash set -ux
make clean autoreconf && ./configure && make -j4 if [[ $? -ne 0 ]]; then # skip build issue exit 125 fi rm ~/.ssh/known_hosts /root/.ssh/known_hosts.old /root/.ssh/known_hosts ./ssh-keyscan 10.245.71.133 > ~/.ssh/known_hosts ./ssh-keygen -H ./ssh-keygen -H # here .old and current should have no diff # no diff = still ok, diff = broken - diff RC matches that diff -q /root/.ssh/known_hosts.old /root/.ssh/known_hosts $ git bisect start V_7_2_P2 V_6_6_P1 Gives me: $ git bisect log # bad: [5c35450a0c901d9375fb23343a8dc82397da5f75] update versions for release # good: [19158b2447e35838d69b2b735fb640d1e86061ea] - (djm) Release OpenSSH 6.6 git bisect start 'V_7_2_P2' 'V_6_6_P1' # bad: [39e2f1229562e1195169905607bc12290d21f021] upstream commit git bisect bad 39e2f1229562e1195169905607bc12290d21f021 # skip: [08c0eebf55d70a9ae1964399e609288ae3186a0c] upstream commit git bisect skip 08c0eebf55d70a9ae1964399e609288ae3186a0c # good: [f067cca2bc20c86b110174c3fef04086a7f57b13] upstream commit git bisect good f067cca2bc20c86b110174c3fef04086a7f57b13 # bad: [fe8a3a51699afbc6407a8fae59b73349d01e49f8] upstream commit git bisect bad fe8a3a51699afbc6407a8fae59b73349d01e49f8 # good: [9010902954a40b59d0bf3df3ccbc3140a653e2bc] upstream commit git bisect good 9010902954a40b59d0bf3df3ccbc3140a653e2bc # bad: [3fdc88a0def4f86aa88a5846ac079dc964c0546a] upstream commit git bisect bad 3fdc88a0def4f86aa88a5846ac079dc964c0546a # bad: [9e06a0fb23ec55d9223b26a45bb63c7649e2f2f2] upstream commit git bisect bad 9e06a0fb23ec55d9223b26a45bb63c7649e2f2f2 # good: [f101d8291da01bbbfd6fb8c569cfd0cc61c0d346] upstream commit git bisect good f101d8291da01bbbfd6fb8c569cfd0cc61c0d346 # bad: [cecb30bc2ba6d594366e657d664d5c494b6c8a7f] upstream commit git bisect bad cecb30bc2ba6d594366e657d664d5c494b6c8a7f # good: [c29811cc480a260e42fd88849fc86a80c1e91038] upstream commit git bisect good c29811cc480a260e42fd88849fc86a80c1e91038 # good: [ec3d065df3a9557ea96b02d061fd821a18c1a0b9] upstream commit git bisect good ec3d065df3a9557ea96b02d061fd821a18c1a0b9 # first bad commit: [cecb30bc2ba6d594366e657d664d5c494b6c8a7f] upstream commit The offending commit you want to report in your upstream bug is: cecb30bc2ba6d594366e657d664d5c494b6c8a7f is the first bad commit commit cecb30bc2ba6d594366e657d664d5c494b6c8a7f Author: d...@openbsd.org <d...@openbsd.org> Date: Sun Jan 18 21:49:42 2015 +0000 upstream commit make ssh-keygen use hostkeys_foreach(). Removes some horrendous code; ok markus@ Upstream accidentally dropped the "non-overwrite" feature of ssh-keygen -H, but it is part of a much bigger rework, therefore this is nothing we just can/want to revert. ** Tags added: needs-upstream-report -- 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/1668093 Title: ssh-keygen -H corrupts already hashed entries Status in openssh package in Ubuntu: Confirmed Bug description: xenial @ 1:7.2p2-4ubuntu2.1 on amd64 has this bug. trusty @ 1:6.6p1-2ubuntu2.8 on amd64 does not have this bug. I have not tested any other ssh versions. The following should reproduce the issue: #ssh-keyscan XXXX > ~/.ssh/known_hosts # ssh root@XXXXX Permission denied (publickey). # ssh-keygen -H /root/.ssh/known_hosts updated. Original contents retained as /root/.ssh/known_hosts.old WARNING: /root/.ssh/known_hosts.old contains unhashed entries Delete this file to ensure privacy of hostnames # ssh root@XXXXXX Permission denied (publickey). # ssh-keygen -H /root/.ssh/known_hosts updated. Original contents retained as /root/.ssh/known_hosts.old WARNING: /root/.ssh/known_hosts.old contains unhashed entries Delete this file to ensure privacy of hostnames # ssh root@XXXXX The authenticity of host 'XXXXXX' can't be established. RSA key fingerprint is XXXXXX. Are you sure you want to continue connecting (yes/no)? # diff known_hosts.old known_hosts 1c1 < |1|BoAbRpUE3F5AzyprJcbjdepeDh8=|x/1AcaLxh45FlShmVQnlgx2qjxY= XXXXX --- > |1|nTPsoLxCugQyZi3pqOa2pc/cX64=|bUH5qwZlZPp8msMGHdLtslf3Huk= XXXXX To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/openssh/+bug/1668093/+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