Slashdot Mirror

← Back to Stories (view on slashdot.org)

Meltdown and Spectre Patches Bricking Ubuntu 16.04 Computers (bleepingcomputer.com)

Posted by msmash on from the things-going-south dept.

An anonymous reader writes: Ubuntu Xenial 16.04 users who updated to receive the Meltdown and Spectre patches are reporting they are unable to boot their systems and have been forced to roll back to an earlier Linux kernel image. The issues were reported by a large number of users on the Ubuntu forums and Ubuntu's Launchpad bug tracker. Only Ubuntu users running the Xenial 16.04 series appear to be affected.

All users who reported issues said they were unable to boot after upgrading to Ubuntu 16.04 with kernel image 4.4.0-108. Canonical, the company behind Ubuntu OS, deployed Linux kernel image 4.4.0-108 as part of a security update for Ubuntu Xenial 16.04 users, yesterday, on January 9. According to Ubuntu Security Notice USN-3522-1 and an Ubuntu Wiki page, this was the update that delivered the Meltdown and Spectre patches.

5 of 233 comments (clear)

  1. Already fixed... by Anonymous Coward · · Score: 5, Informative

    Kernel 4.4.0-109, which fixes this problem, has already been pushed out.
    Apparently, the PTI fix was not quite backported correctly.
    For details, see https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1741934

  2. Not bricked #2305473 by Fly+Swatter · · Score: 5, Informative

    Press down arrow at boot menu screen.

  3. Failed reboot is not "bricking" by Antique+Geekmeister · · Score: 5, Informative

    Failing to use a particular new kernel is not "bricking". Bricking, as commonly used, means the physical hardware is unrecoverable and needs to be replaced. Recovering a failed Ubuntu kernel means being able to select a different kernel to boot with. This means console access or access to the disk image. These are problematic and can disable production servers. But it's much less destructive than ruining the physical hardware.

  4. Re:Bricked!!?!?! Oh wow! by k.a.f. · · Score: 5, Informative

    Close, but no cigar. When you have to throw the device away, then it's bricked.

  5. Re:A web page can now own your system by scdeimos · · Score: 5, Informative

    Meltdown cannot be exploited using Javascript.

    Yes it can, even WebKit says so...

    Meltdown means that userland code, such as JavaScript running in a web browser, can read kernel memory. Not all CPUs are affected by Meltdown and Meltdown is being mitigated by operating system changes. Mounting a Meltdown attack via JavaScript running in WebKit requires first bypassing branch-based security checks, like in the case of a Spectre attack. Therefore, Spectre mitigations that fix the branch problem also prevent an attacker from using WebKit as the starting point for Meltdown.

    REF: https://webkit.org/blog/8048/w...

    Most browser vendors are implementing many changes to mitigate Meltdown and Spectre, including things like reducing the precision of high-fidelity timers from 5us to 20us +/- 20us, disabling SharedArrayBuffers and recompiling with Spectre-aware compilers.