Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> wrote:
> > > if (shift) {
> > > - if (ctx->stmt_len > 0 && div_round_up(masklen, BITS_PER_BYTE) > 1) {
> > > + if (masklen > BITS_PER_BYTE) {
> >
> > I think this is right but binop xfer
> > won't remove the inserted byteorder conversion
> > in case the shift is to be removed by adjusting
> > a constant right hand side value.
>
> ctx->stmt_len > 0 is also set from stmt_evaluate_{ct,meta}() so this
> transformation is restricted to statements.
>
> I was conservative edecd58755a8 with ("evaluate: support shifts larger than
> the width of the left operand") to restrict this transformation to
> statements only.
>
> Do you think think this applies to other cases too?
>
> BTW, whatever the final fix is, Fixes: tag for this should be:
>
> Fixes: 668c18f67203 ("evaluate: place byteorder conversion before rshift in payload statement")
I don't think this is a regression, I do not think it has worked before.
table ip6 t {
map mapv6 {
typeof ip6 dscp : meta mark
elements = { cs1 : 0x0000002a }
}
chain output {
type filter hook output priority filter; policy accept;
meta mark set ip6 dscp map @mapv6
meta mark 0x0000002a counter
ip6 dscp @mapv6 counter
ip6 dscp cs1 counter
}
}
A "ping6 -q -Q 0x20 ::1 -c1" should cause all counters
in above ruleset to increment, but that is not the case.
Even before above commit.
