At arm's length

Torvalds patch lets virus in

With open-source software gaining more and more momentum, it's hardly surprising to find that viruses for Linux are beginning to appear, the most recent being Virus.Linux.Bi.a/Virus.Win32.Bi.a - a cross-platform virus that can affect both Windows- and Linux-based systems. However, it proved ineffective on certain Linux systems due to a bug in versions that have been compiled using a kernel option known as REGPARM enabled by default.

It seems ironic, then, that the creator of this virus inadvertently highlighted this bug to Linus Torvalds, who promptly patched his version of the Linux kernel - which will roll out in the 2.6.17 version - to fix the problem.

But what's more ironic is that Torvalds' patch now allows this particular virus to run on all Linux systems. In his defence, Torvalds pointed out that his fix wasn't placing Linux at risk, and that the virus in question was simply a proof of concept, rather than a genuine malicious payload. However, he also noted that "any serious bad guy" would have been able to overcome the now-fixed compiler bug in order to get the virus working without too much effort.

As yet, there have been no reports of malignant variants of Linux.Bi.a in the wild, so Linux users can rest easy for now. However, it's really only a matter of time before this proof of concept code is picked up by genuine virus writers.