[ovs-dev] [PATCH 1/3] dpif: Fix NULL dereference fetching non-UFID flow.

[Ben Pfaff]

On Thu, Dec 11, 2014 at 02:48:46PM -0800, Joe Stringer wrote:
> On 11 December 2014 at 14:05, Ben Pfaff <blp at nicira.com> wrote:
> > On Wed, Dec 03, 2014 at 02:24:46PM -0800, Joe Stringer wrote:
> >> The UFID parameter to dpif_flow_get() is optional, but the current
> >> implementation dereferences it to initialize part of the output flow.
> >> This field is filled in by the dpif implementation, so don't initialize
> >> it here.
> >>
> >> This could cause a NULL dereference if a dpif_flow_get() caller doesn't
> >> provide a UFID. Currently there are no such callers, but the next patch
> >> will introduce one.
> >>
> >> Signed-off-by: Joe Stringer <joestringer at nicira.com>
> >
> > Acked-by: Ben Pfaff <blp at nicira.com>
> >
> > The title of the patch makes this sound like a bug fix, but the
> > explanation later on sounds like it would only be a real bug if the
> > callers were changed.  Is there a bug that can currently be triggered?
> 
> No, it cannot be triggered currently. Perhaps this could be rolled
> into the next patch, or renamed.

I'd just adjust the commit message to make it even clearer.  Maybe
something like "This does not fix any existing bug because every caller
currently passes in a UFID."