Re: CVE request: information leak / potential crash in sys_move_pages

[Eugene Teo <eugeneteo () kernel sg>]

On 02/07/2010 09:50 AM, Marcus Meissner wrote:
> Hi,
>
> I spotted a problem in sys_move_pages, where "node" value is read from userspace,
> but not limited to the node set within the kernel itself.
>
> Due to the bit tests in mm/migrate.c:do_move_pages it is easy to read out
> the kernel memory (as node can also be negative).
>
> (The node_isset and node_state functions just map to test_bit, which has
>   no limiter in the normal implementations.)
>
> There also is (in my eyes) the chance we can corrupt kernel memory later on
> if we have all the right bits setup, but I did not research this further.
>
> Issue was present starting as sys_move_pages was introduced in 2.6.18.
> Solved in mainline by commit below.
>
> Needs a CVE for information leakage at least.

Thanks, please use CVE-2010-0415.

Eugene