On Thu, Oct 15, 2026 at 02:55:23PM +0200, Johannes Berg wrote: > On Thu, 2026-10-15 at 08:52 -0400, Michael S. Tsirkin wrote: > > On Thu, Oct 15, 2026 at 02:47:01PM +0200, Johannes Berg wrote: > > > On Thu, 2026-10-15 at 08:41 -0400, Michael S. Tsirkin wrote: > > > > virtio_net_hdr_to_skb() refuses packets whose checksum metadata > > > > it cannot make sense of, but the vector raw transport ignored > > > > its return value: rejected packets went on into the stack with > > > > their metadata unvalidated. > > > > > > > > Propagate the failure. > > > > > > > > Assisted-by: LLM > > > > Signed-off-by: Michael S. Tsirkin <[email protected]> > > > > --- > > > > arch/um/drivers/vector_transports.c | 4 +++- > > > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > > > > > diff --git a/arch/um/drivers/vector_transports.c > > > > b/arch/um/drivers/vector_transports.c > > > > index e1fb2a76fdff..8b7548458663 100644 > > > > --- a/arch/um/drivers/vector_transports.c > > > > +++ b/arch/um/drivers/vector_transports.c > > > > @@ -210,7 +210,9 @@ static int raw_verify_header( > > > > return 1; > > > > > > > > skb_set_network_header(skb, ETH_HLEN); > > > > - virtio_net_hdr_to_skb(skb, vheader, > > > > virtio_legacy_is_little_endian()); > > > > + if (virtio_net_hdr_to_skb(skb, vheader, > > > > + virtio_legacy_is_little_endian()) < 0) > > > > + return -1; > > > > return 0; > > > > > > > > > > Seems it'd be simpler to just > > > > > > return virtio_net_hdr_to_skb(...); > > > > > > As far as I can tell, the function only returns -EINVAL or 0 (never a > > > positive value), and the caller only cares about negative (error) or > > > positive (no checksum needed), so that'd be equivalent? > > > > > > johannes > > > > if raw_verify_header can safely return any errno - i did not want to > > audit it. > > You already used an LLM and still didn't want to? ;-)
I don't really trust it to do code audits especially in code I do not test. > I checked briefly (by hand) and it seems fine, it's assigned to the > function pointer, which only has two callers on the _kern.c side. > > johannes Thanks, will make the change. -- MST
