Re: invalidly encoded strings

Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
> Tom Lane wrote:
>> Those should be checked already --- if not, the right fix is still to
>> fix it there, not in per-datatype code. I think we are OK though,
>> eg see "need_transcoding" logic in copy.c.

> Well, a little experimentation shows that we currently are not OK:
> in foo.data:
> \366\66

I looked at this and found that the problem is that
CopyReadAttributesText() does backslash conversions and doesn't validate
the result.

My proposal at this point is that both scan.l and CopyReadAttributesText
need to guarantee that the result of de-escaping is valid in the
database encoding: they should reject \0 and check validity of multibyte
characters. You could optimize this fairly well (important in the COPY
case) by not redoing verifymbstr unless you'd seen at least one
numerical backslash-escape that set the high bit.

regards, tom lane