[ovs-dev] [PATCH net] net: ovs: flow: fix potential illegal memory access in __parse_flow_nlattrs

[Jesse Gross]

On Sat, Sep 7, 2013 at 12:41 AM, Daniel Borkmann <dborkman at redhat.com> wrote:
> In function __parse_flow_nlattrs(), we check for condition
> (type > OVS_KEY_ATTR_MAX) and if true, print an error, but we do
> not return from this function as in other checks. It seems this
> has been forgotten, as otherwise, we could access beyond the
> memory of ovs_key_lens, which is of ovs_key_lens[OVS_KEY_ATTR_MAX + 1].
> Hence, a maliciously prepared nla_type from user space could access
> beyond this upper limit.
>
> Introduced by 03f0d916a ("openvswitch: Mega flow implementation").
>
> Signed-off-by: Daniel Borkmann <dborkman at redhat.com>
> Cc: Andy Zhou <azhou at nicira.com>

Yeah, looks like a mistake to me.

Acked-by: Jesse Gross <jesse at nicira.com>