** Description changed: [Impact] + With latest apache 2.4.29-1ubuntu4.7 published to 18.04 LTS bionic, when running ssllabs.com/ssltest against it to verify the configuration it leaves 2 apache processes using 100% indefinitely. - * An explanation of the effects of the bug on users and - - * justification for backporting the fix to the stable release. - - * In addition, it is helpful, but not required, to include an - explanation of how the upload fixes this bug. + Downgrading to 2.4.29-1ubuntu4.6 make it not reproducible anymore. [Test Case] + We didn't find a reproducer that didn't involve https://ssllabs.com/ssltest, so the test case needs a publicly facing server with a DNS record. - * detailed instructions how to reproduce the bug + On a test system that has a public IP and is reachable via https on a hostname (not just IP): + sudo apt update + sudo apt install apache2 + sudo a2enmod ssl + sudo a2ensite default-ssl.conf + sudo service apache2 restart - * these should allow someone who is not familiar with the affected - package to reproduce the bug and verify that the updated package fixes - the problem. + In a terminal, monitor the apache2 processes CPU usage with top. + + Go to https://www.ssllabs.com/ssltest/ and input the url to your test + server, using https. After a few seconds, the site will ask you if it + should ignore the certificate error, confirm, and let it continue the + test. + + After a few minutes, the test will finish and you will get a report. Go + back to the terminal where top is running, and the apache2 processes + will be spinning and using CPU, even though there isn't anymore traffic. + + With the fixed packages, the apache processes will remain idle. + [Regression Potential] - * discussion of how regressions are most likely to manifest as a result + * discussion of how regressions are most likely to manifest as a result of this change. - * It is assumed that any SRU candidate patch is well-tested before - upload and has a low overall risk of regression, but it's important - to make the effort to think about what ''could'' happen in the - event of a regression. + * It is assumed that any SRU candidate patch is well-tested before + upload and has a low overall risk of regression, but it's important + to make the effort to think about what ''could'' happen in the + event of a regression. - * This both shows the SRU team that the risks have been considered, - and provides guidance to testers in regression-testing the SRU. + * This both shows the SRU team that the risks have been considered, + and provides guidance to testers in regression-testing the SRU. [Other Info] - - * Anything else you think is useful to include - * Anticipate questions from users, SRU, +1 maintenance, security teams and the Technical Board - * and address these questions in advance + + * Anything else you think is useful to include + * Anticipate questions from users, SRU, +1 maintenance, security teams and the Technical Board + * and address these questions in advance [Original Description] With latest apache 2.4.29-1ubuntu4.7 published to 18.04 LTS bionic, when running ssllabs.com/ssltest against it to verify the configuration it leaves 2 apache processes using 100% indefinitely. Downgrading to 2.4.29-1ubuntu4.6 make it not reproducible anymore. So far i do not know if it is easy/likely to hit this case in normal https usage or only triggered by that testing site. But given that this is backported to LTS and allows easy DoS maybe the 4.7 should be backed out? So likely regression in the update to 4.7 having only single fix: https://bugs.launchpad.net/ubuntu/+source/apache2/+bug/1833039 Extra info observed when that ssltest is over but processes are still there using up cpu: /server-status shows both processes 25234,25235 here in 'Reading' state: Srv PID Acc M CPU SS Req Conn Child Slot Client Protocol VHost Request 0-0 25234 0/0/0 W 0.00 0 0 0.0 0.00 0.00 127.0.0.1 http/1.1 ip-172-30-1-107.eu-west-1.compu GET /server-status HTTP/1.1 0-0 25234 0/0/0 R 0.00 641 0 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 0.00 505 2 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 0.00 501 0 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 0.00 500 0 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 0.00 494 0 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 0.00 604 0 0.0 0.00 0.00 64.41.200.106 http/1.1 1-0 25235 0/1/1 _ 0.00 604 0 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 16.93 596 0 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 0.01 595 1 0.0 0.00 0.00 64.41.200.106 http/1.1 1-0 25235 0/0/0 R 0.00 679 0 0.0 0.00 0.00 64.41.200.106 http/1.1 netstat on system: tcp6 1 0 172.30.1.57:443 64.41.200.106:58658 CLOSE_WAIT tcp6 1 0 172.30.1.57:443 64.41.200.107:60842 CLOSE_WAIT with on other connections to 443 port.
** Description changed: [Impact] With latest apache 2.4.29-1ubuntu4.7 published to 18.04 LTS bionic, when running ssllabs.com/ssltest against it to verify the configuration it leaves 2 apache processes using 100% indefinitely. Downgrading to 2.4.29-1ubuntu4.6 make it not reproducible anymore. [Test Case] We didn't find a reproducer that didn't involve https://ssllabs.com/ssltest, so the test case needs a publicly facing server with a DNS record. On a test system that has a public IP and is reachable via https on a hostname (not just IP): sudo apt update sudo apt install apache2 sudo a2enmod ssl sudo a2ensite default-ssl.conf sudo service apache2 restart In a terminal, monitor the apache2 processes CPU usage with top. Go to https://www.ssllabs.com/ssltest/ and input the url to your test server, using https. After a few seconds, the site will ask you if it should ignore the certificate error, confirm, and let it continue the test. After a few minutes, the test will finish and you will get a report. Go back to the terminal where top is running, and the apache2 processes will be spinning and using CPU, even though there isn't anymore traffic. With the fixed packages, the apache processes will remain idle. - [Regression Potential] * discussion of how regressions are most likely to manifest as a result of this change. * It is assumed that any SRU candidate patch is well-tested before upload and has a low overall risk of regression, but it's important to make the effort to think about what ''could'' happen in the event of a regression. * This both shows the SRU team that the risks have been considered, and provides guidance to testers in regression-testing the SRU. [Other Info] - - * Anything else you think is useful to include - * Anticipate questions from users, SRU, +1 maintenance, security teams and the Technical Board - * and address these questions in advance + While investigating this issue, another fix for an openssl 1.1.1 issue was found in the apache upstream git repo which involves http2 and how the code handles SSL_read() return values: https://github.com/apache/httpd/commit/644cff9977efa322fe6c0ae3357a5b8cb1eeec11 + No upstream bug was found, nor could I come up with a reproducer case, but it seemed sensible to include that patch in this SRU, which was, after all, triggered by the openssl 1.1.1 upgrade in bionic. [Original Description] With latest apache 2.4.29-1ubuntu4.7 published to 18.04 LTS bionic, when running ssllabs.com/ssltest against it to verify the configuration it leaves 2 apache processes using 100% indefinitely. Downgrading to 2.4.29-1ubuntu4.6 make it not reproducible anymore. So far i do not know if it is easy/likely to hit this case in normal https usage or only triggered by that testing site. But given that this is backported to LTS and allows easy DoS maybe the 4.7 should be backed out? So likely regression in the update to 4.7 having only single fix: https://bugs.launchpad.net/ubuntu/+source/apache2/+bug/1833039 Extra info observed when that ssltest is over but processes are still there using up cpu: /server-status shows both processes 25234,25235 here in 'Reading' state: Srv PID Acc M CPU SS Req Conn Child Slot Client Protocol VHost Request 0-0 25234 0/0/0 W 0.00 0 0 0.0 0.00 0.00 127.0.0.1 http/1.1 ip-172-30-1-107.eu-west-1.compu GET /server-status HTTP/1.1 0-0 25234 0/0/0 R 0.00 641 0 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 0.00 505 2 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 0.00 501 0 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 0.00 500 0 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 0.00 494 0 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 0.00 604 0 0.0 0.00 0.00 64.41.200.106 http/1.1 1-0 25235 0/1/1 _ 0.00 604 0 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 16.93 596 0 0.0 0.00 0.00 64.41.200.107 http/1.1 1-0 25235 0/1/1 _ 0.01 595 1 0.0 0.00 0.00 64.41.200.106 http/1.1 1-0 25235 0/0/0 R 0.00 679 0 0.0 0.00 0.00 64.41.200.106 http/1.1 netstat on system: tcp6 1 0 172.30.1.57:443 64.41.200.106:58658 CLOSE_WAIT tcp6 1 0 172.30.1.57:443 64.41.200.107:60842 CLOSE_WAIT with on other connections to 443 port. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1836329 Title: Regression running ssllabs.com/ssltest causes 2 apache process to eat up 100% cpu, easy DoS To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apache2/+bug/1836329/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
