Red Hat Bugzilla – Bug 835898
Bug in DNS cache causes connections until restart of libcurl-using processes
Last modified: 2015-07-22 01:42:47 EDT
+++ This bug was initially created as a clone of Bug #835639 +++ Description of problem: A bug fixed in version 7.20 of libcurl is affecting a lot of my customers using software that depends on libcurl and maintains long-lived HTTP connection pools. Older versions had race conditions that "locked" stale DNS lookups in memory and prevented fresh DNS lookups. When IP addresses change, the library fails to detect the change and keeps accessing the stale address. The bug fix is here: http://sourceforge.net/tracker/index.php?func=detail&aid=2891595&group_id=976&atid=100976 I don't really guess you'll backport this, but I need to file this and get confirmation for my customers so that a decision on whether to junk use of RH-supplied libcurl will be the only recourse. Version-Release number of selected component (if applicable): All versions < 7.20.0 of libcurl, including the one in RH5. How reproducible: It requires software that relies on connection pooling of libcurl handles and uses multiple threads with some load. Steps to Reproduce: 1.Load test software using a particular destination name/address. 2.Change the DNS entry. 3.Observe new connections inheriting use of the old address. Actual results: The DNS change is not picked up. Expected results: New connections should see the change without restarting the process. Additional info: --- Additional comment from kdudka@redhat.com on 2012-06-27 15:30:23 CEST --- upstream commit: https://github.com/bagder/curl/commit/fb5f332
This request was evaluated by Red Hat Product Management for inclusion in the current release of Red Hat Enterprise Linux. Because the affected component is not scheduled to be updated in the current release, Red Hat is unable to address this request at this time. Red Hat invites you to ask your support representative to propose this request, if appropriate, in the next release of Red Hat Enterprise Linux.
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/RHSA-2015-1254.html