@(#)Mordre Labs advisory 0x0005: Several buffer overruns in PostgreSQL

//@(#) Mordred Labs advisory 0x0005

Release data: 23/08/02
Name: Several buffer overruns in PostgreSQL
Versions affected: all versions
Risk: from average to low

--[ Description:

PostgreSQL provides you with several builint geo types
(circle,polygon,box...etc).
Unfortunately the code for geo functions written in a very insecure style
and should be totally rewritten, as a quick search revealed this:

---[ Details:

1)

Upon invoking a polygon(integer, circle) function
a src/backend/utils/adt/geo_ops.c:circle_poly() function will gets called,
which suffers from a buffer overflow.

2) A src/backend/adt/utils/geo_ops.c:path_encode() fails to detect a buffer
overrun condition. It is called in multiple places, the most
interesting are path_out() and poly_out() functions.

3) Upon converting a char string to a path object, a
src/backend/utils/adt/geo_ops.c:path_in() function will gets called,
which suffers from a buffer overrun, caused by a very long argument.

4) A src/backend/utils/adt/geo_ops.c:poly_in() function fails to detect a
buffer
overrun condition caused by a very long argument.

5) A src/backend/utils/adt/geo_ops.c:path_add() also fails to detect a
simple buffer
overrun.

6)

And finally, a truly dumb feature (not a security related though) in
postmaster:
$ postmaster -o `perl -e 'print "\x66" x 1200'`
Segmentation fault (core dumped)

--[ How to reproduce:

I only show how to reproduce a first buffer overrun condition, as the others
too memory consuming :-)

1)

template1=# select polygon(268435455,'((1,2),3)'::circle);
pqReadData() -- backend closed the channel unexpectedly.
This probably means the backend terminated abnormally
before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.
!#

--[ Solution

Drop the vulnerable functions.

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