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Re: CVS commit: src/sys/net



Christos Zoulas wrote:
> On Dec 29, 10:09pm, alnsn%yandex.ru@localhost (Alexander Nasonov) wrote:
> | Not sure FreeBSD got BPF_IND case right. They basically disabled using
> | big positive values of pc->k for small negative values. They could just
> | copy code from BPF_ABS case:
> | 
> | > +                 if (k > buflen || sizeof(int16_t) > buflen - k) {
> | 
> | but they didn't. Can we assume that loads with negative offsets relative
> | to X (e.g. P[X-1:4]) are not allowed by bpf?
> 
> I suppose by turning k unsigned, they really want to disable negative offsets.
> We could allow them if needed, but at that point it is better to make k 
> signed.

I wish they stated it explicitly in bpf(4). Can I document it in our
bpf(4)?

Alex


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