Bug 678569
| Summary: | SDL_BlitCopyOverlap assumes memcpy operates in order while SSE3 version operates from back to front | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Product: | Red Hat Enterprise Linux 6 | Reporter: | Petr Pisar <ppisar> | ||||||
| Component: | SDL | Assignee: | Petr Pisar <ppisar> | ||||||
| Status: | CLOSED ERRATA | QA Contact: | Lukáš Zachar <lzachar> | ||||||
| Severity: | medium | Docs Contact: | |||||||
| Priority: | low | ||||||||
| Version: | 6.1 | CC: | ovasik, ppisar, psplicha, twoerner | ||||||
| Target Milestone: | rc | Keywords: | Patch | ||||||
| Target Release: | --- | ||||||||
| Hardware: | x86_64 | ||||||||
| OS: | Linux | ||||||||
| Whiteboard: | |||||||||
| Fixed In Version: | SDL-1.2.14-3.el6 | Doc Type: | Bug Fix | ||||||
| Doc Text: |
Cause
Calling SDL_BlitSurface() on overlaping rectangles while
running on SSE3 optimized standard C library.
Consequence
Rectangle bitmaps content is corrupted what produces
garbage on the screen.
Fix
Internal SDL_BlitCopyOverlap() function has been fixed to
copy bitmaps between overlapping areas correctly.
Result
SDL_BlitSurface() function performs correctly even if
standard C library does not implement memcpy() safely for
operation on overlapping memory areas.
|
Story Points: | --- | ||||||
| Clone Of: | 669844 | Environment: | |||||||
| Last Closed: | 2012-04-03 15:20:31 UTC | Type: | --- | ||||||
| Regression: | --- | Mount Type: | --- | ||||||
| Documentation: | --- | CRM: | |||||||
| Verified Versions: | Category: | --- | |||||||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||||
| Cloudforms Team: | --- | Target Upstream Version: | |||||||
| Embargoed: | |||||||||
| Attachments: |
|
||||||||
|
Description
Petr Pisar
2011-02-18 13:25:51 UTC
Created attachment 479499 [details]
Fix from upstream
Created attachment 479500 [details]
Reproducer
Requires new glibc, SSE3 CPU, and little of luck.
Current glibc-2.12-1.19.el6.x86_64 does not provided affected memcpy(), so the SDL bug does not exhibit now. 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 unfortunately unable to address this request at this time. Red Hat invites you to ask your support representative to propose this request, if appropriate and relevant, in the next release of Red Hat Enterprise Linux. If you would like it considered as an exception in the current release, please ask your support representative.
Technical note added. If any revisions are required, please edit the "Technical Notes" field
accordingly. All revisions will be proofread by the Engineering Content Services team.
New Contents:
Cause
Calling SDL_BlitSurface() on overlaping rectangles while
running on SSE3 optimized standard C library.
Consequence
Rectangle bitmaps content is corrupted what produces
garbage on the screen.
Fix
Internal SDL_BlitCopyOverlap() function has been fixed to
copy bitmaps between overlapping areas correctly.
Result
SDL_BlitSurface() function performs correctly even if
standard C library does not implement memcpy() safely for
operation on overlapping memory areas.
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. http://rhn.redhat.com/errata/RHBA-2012-0446.html |