Re: [PATCH bpf v2 2/2] bpf: ensure main program has an extable

From: Krister Johansen
Date: Thu Jun 08 2023 - 20:09:22 EST


On Thu, Jun 08, 2023 at 03:01:36PM -0700, Alexei Starovoitov wrote:
> On Wed, Jun 7, 2023 at 2:04 PM Krister Johansen <kjlx@xxxxxxxxxxxxxxxxxx> wrote:
> > Cc: stable@xxxxxxxxxxxxxxx
> > Fixes: 1c2a088a6626 ("bpf: x64: add JIT support for multi-function programs")
> > Signed-off-by: Krister Johansen <kjlx@xxxxxxxxxxxxxxxxxx>
> > ---
> > kernel/bpf/verifier.c | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
> > index 5871aa78d01a..d6939db9fbf9 100644
> > --- a/kernel/bpf/verifier.c
> > +++ b/kernel/bpf/verifier.c
> > @@ -17242,6 +17242,7 @@ static int jit_subprogs(struct bpf_verifier_env *env)
> > prog->jited = 1;
> > prog->bpf_func = func[0]->bpf_func;
> > prog->jited_len = func[0]->jited_len;
> > + prog->aux->extable = func[0]->aux->extable;
>
> Why not to do this hunk and what I suggested earlier: start from func=1 ?
> That will address double ksym insertion that Yonghong mentioned.

Sure thing. Yonghong and you have convinced me.

I'll send out a v3 with all changes requested so far.

-K