APPLIED[D]: [SRU] [X/B/C/D] [PATCH v2 0/1] openvswitch: fix kernel buffer overflow

Seth Forshee seth.forshee at canonical.com
Mon Apr 8 12:08:02 UTC 2019


On Fri, Apr 05, 2019 at 09:31:52AM +0200, Andrea Righi wrote:
> Buglink: https://bugs.launchpad.net/bugs/1813244
> 
> [Impact]
> 
>  * Flow action buffer can be incorrectly resized to contain the newly added
>    action entries: the buffer is always resized multiplying the previous size
>    by 2, but this might be not enough if the requested size is bigger than
>    previous_size*2, causing a buffer overflow
> 
>  * The fix correctly resizes the buffer to prevent the buffer overflow
>    and potential memory corruptions
> 
>  * This bug can be triggered potentially on any architecture, but it is very
>    likely to happen on i386 running the following test case
> 
> [Test Case]
> 
>  * run this openvswitch test case:
>    https://launchpadlibrarian.net/416589265/lp1262692
> 
> [Fix]
> 
>  * Instead of resizing the buffer by a factor of 2, use
>    max(current_size * 2, current_size + requested_size)
> 
> [Regression Potential]
> 
>  * Fix has been tested on the affected platform and verified using slub_debug.
>    It is an upstream fix and also a very small patch (one-liner basically), so
>    backport changes are minimal.
> 
> Changes in v2:
>  - fix has been merged upstream (add reference to the proper sha1)

Applied to disco/master-next, thanks!



More information about the kernel-team mailing list