Bug 43943

Summary: SHMCB crash due to misalignment and GCC 4 optimization
Product: Apache httpd-2 Reporter: Rainer Jung <rainer.jung>
Component: mod_sslAssignee: Apache HTTPD Bugs Mailing List <bugs>
Status: RESOLVED LATER    
Severity: normal Keywords: MassUpdate, PatchAvailable
Priority: P2    
Version: 2.0.61   
Target Milestone: ---   
Hardware: Sun   
OS: Solaris   

Description Rainer Jung 2007-11-22 14:47:57 UTC 
This is the same issue as BZ 38838, but here for Apache 2.0.
It has been fixed for httpd 2.2 in March 2006 with

http://svn.apache.org/viewvc?view=rev&revision=382799

The same patch fixes it for httpd 2.0.

The problem was noticed with httpd 2.0.61 compiled with gcc 4.1.2.

The memset() used in shmcb_safe_clear() got compiled as

0xfe2d726c <ssl_scache_shmcb_store+732>:        clr  [ %l1 ]
0xfe2d7270 <ssl_scache_shmcb_store+736>:        clr  [ %l1 + 4 ]
0xfe2d7274 <ssl_scache_shmcb_store+740>:        clr  [ %l1 + 8 ]

and the address in the register is not aligned for clr:

l1             0xfe435c17       -29139945
Comment 1 William A. Rowe Jr. 2018-11-07 21:08:46 UTC 
Please help us to refine our list of open and current defects; this is a mass update of old and inactive Bugzilla reports which reflect user error, already resolved defects, and still-existing defects in httpd.

As repeatedly announced, the Apache HTTP Server Project has discontinued all development and patch review of the 2.2.x series of releases. The final release 2.2.34 was published in July 2017, and no further evaluation of bug reports or security risks will be considered or published for 2.2.x releases. All reports older than 2.4.x have been updated to status RESOLVED/LATER; no further action is expected unless the report still applies to a current version of httpd.

If your report represented a question or confusion about how to use an httpd feature, an unexpected server behavior, problems building or installing httpd, or working with an external component (a third party module, browser etc.) we ask you to start by bringing your question to the User Support and Discussion mailing list, see [https://httpd.apache.org/lists.html#http-users] for details. Include a link to this Bugzilla report for completeness with your question.

If your report was clearly a defect in httpd or a feature request, we ask that you retest using a modern httpd release (2.4.33 or later) released in the past year. If it can be reproduced, please reopen this bug and change the Version field above to the httpd version you have reconfirmed with.

Your help in identifying defects or enhancements still applicable to the current httpd server software release is greatly appreciated.