BUG #5275: validate_exec in port/exec.c only reads u/g/o, not ACLs

The following bug has been logged online:

Bug reference:      5275
Logged by:          James Bellinger
Email address:      jfb@zer7.com
PostgreSQL version: 8.4.2
Operating system:   Ubuntu 9.10
Description:        validate_exec in port/exec.c only reads u/g/o, not ACLs
Details:

Howdy,

I'm not certain of the actual *purpose* for this function even checking in
the first place, but the result is that, if Postgres gets its access via an
ACL, it will say 'invalid binary' here and there, will not be able to find
its own executables, etc. I can see no purpose for this function.

That said, currently, the reason it gives these errors is that it only
checks user/group/other. Linux ACLs are not checked. If this function really
needs to exist as is, this ought to be fixed.

Thanks

James