Re: BUG #1270: stack overflow in thread in fe_getauthname

Tom Lane wrote:
> "PostgreSQL Bugs List" <pgsql-bugs@postgresql.org> writes:
> > With the THREAD_SAFETY changes, a buffer is defined on the stack as:
> > char       pwdbuf[BUFSIZ];
> > This buffer overflows the stack when used in a thread.  As the application
> > creating the thread cannot be modified to increase the stack size, it would
> > probably be prudent to reduce this buffer size (I believe that BUFSIZ is
> > around 8192 bytes on most modern Unix implementations).
>
> No, it would be prudent to fix the app.  While this one particular
> buffer might be larger than needed, we are *not* going to buy into the
> notion that libpq needs to run successfully in an 8K stack.  This
> particular problem is only the tip of the iceberg; hewing to any
> such limit is going to require far more drastic changes that just don't
> seem worthwhile.

Agreed.  I fixed the cases were the buffers was really too large, but
there is no way we could run on an 8k stack.  I assume you were having
problems where you were doing multiple lookups in a single thread but am
not sure that ever really happens.

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