Re: [PATCHES] Escape handling in strings

From: Andrew Dunstan <andrew(at)dunslane(dot)net>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Rod Taylor <pg(at)rbt(dot)ca>, Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org>, Christopher Kings-Lynne <chriskl(at)familyhealth(dot)com(dot)au>
Subject: Re: [PATCHES] Escape handling in strings
Date: 2005-06-16 15:25:23
Message-ID: 42B199E3.8000102@dunslane.net
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers pgsql-patches


[switched to -hackers]

Tom Lane wrote:

>Rod Taylor <pg(at)rbt(dot)ca> writes:
>
>
>>It probably won't be any worse than when '' was rejected for an integer
>>0.
>>
>>
>
>That analogy is *SO* far off the mark that I have to object.
>
>Fooling with quoting rules will not simply cause clean failures, which
>is what you got from ''-no-longer-accepted-by-atoi. What it will cause
>is formerly valid input being silently interpreted as something else.
>That's bad enough, but it gets worse: formerly secure client code may
>now be vulnerable to SQL-injection attacks, because it doesn't know how
>to quote text properly.
>
>What we are talking about here is an extremely significant change with
>extremely serious consequences, and imagining that it is not will be
>a recipe for disaster.
>
>
>
>
All true. Conversely, there does need to be a path for us to get to
standard behaviour.

I think we're going to need to provide for switchable behaviour, as ugly
as that might be (looking briefly at scan.l it looks like the simplest
way would be a separate state for being inside standard strings, with
the choice of state being made conditionally in the {xqstart} rule).

We can't just break backwards compatibility overnight like this.

cheers

andrew

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Hans-Jürgen Schönig 2005-06-16 15:29:47 Re: Autovacuum in the backend
Previous Message Alvaro Herrera 2005-06-16 15:11:20 Re: Autovacuum in the backend

Browse pgsql-patches by date

  From Date Subject
Next Message Tom Lane 2005-06-16 16:00:41 Re: [PATCHES] Escape handling in strings
Previous Message Christof Petig 2005-06-16 14:45:58 Re: libecpg (8.0 and CVS) hits a gcc bug on powerpc