Polls

Topics

GCC Compiler 4.3.0 exposes a Linux / BSD kernel bug

Posted by Vivek on Wednesday March 19, 08 @7:13 pm

Since version 4.3, gcc changed its behavior concerning the x86/x86-64 ABI and the direction flag, that is it now assumes that the direction flag is cleared at the entry of a function and it doesn't clear once more if needed. According to LWN article GCC 4.3.0 exposes a kernel bug:

A change to GCC for a recent release coupled with a kernel bug has created a messy situation, with possible security implications. GCC changed some assumptions about x86 processor flags, in accordance with the ABI standard, that can lead to memory corruption for programs built with GCC 4.3.0. No one has come up with a way to exploit the flaw, at least yet, but it clearly is a problem that needs to be addressed.

=> GCC 4.3.0 exposes a kernel bug (via ./)

Want to stay up to date with the latest Linux tips, news and announcements? Subscribe to our free e-mail newsletter or full RSS feed to get all updates. You can Email this page to a friend.

You may also be interested in...

Discussion on This Article:

  1. marc Says:

    FreeBSD doesn’t use GCC4.3 for kernel and world.

    gcc version 4.2.1 20070719 [FreeBSD] this is the version in FreeBSD 7.0R. So it’s *maybe* a problem for the Linux kernel, while using anything bleeding edge.

  2. Nilesh Says:

    At least Fedora developers release application versions after testing and changing them a bit. :)

    I have 4.1.2. I updated two days ago but gcc hasn’t changed.

    BTW, what happened to the kernel bug ??

    When I updated two days ago, kernel was updated to

    2.6.24.3-34.fc8

    This is quite late after the kernel 2.6.24 was released.

  3. tirumala rao Says:

    hi,
    I have fedora 3 , what shall I do to install gcc4.3 , to work with opanMP.

    Thanking you

Leave a Reply

We encourage your comments, and suggestions. But please stay on topic, be polite, and avoid spam. Thank you very much for stopping by our site!

XHTML: You can use these tags: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>

*
To prove you're a person (not a spam script), type the security word shown in the picture. Click on the picture to hear an audio file of the word.
Click to hear an audio file of the anti-spam word

Tags: , , , , , , , , , , ~ Last updated on: March 19, 2008

Copyright © 2004-2008 nixCraft. All rights reserved - TOS/Disclaimer - Privacy policy - Sitemap - Powered by Open source software.