Horton

Re: Schema variables - new implementation for Postgres 15

Sergey Shinderuk <s.shinderuk@postgrespro.ru>

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From: Sergey Shinderuk <s.shinderuk@postgrespro.ru>
To: Pavel Stehule <pavel.stehule@gmail.com>
Cc: Tomas Vondra <tomas.vondra@enterprisedb.com>, Julien Rouhaud <rjuju123@gmail.com>, dean.a.rasheed@gmail.com, er@xs4all.nl, joel@compiler.org, pgsql-hackers@lists.postgresql.org
Date: 2022-11-14T07:00:38Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Allow underscores in integer and numeric constants.

  2. Remove special outfuncs/readfuncs handling of RangeVar.catalogname.

  3. Remove extra space from dumped ALTER DEFAULT PRIVILEGES.

  4. Create FKs properly when attaching table as partition

  5. psql: improve tab-complete's handling of variant SQL names.

On 13.11.2022 20:59, Pavel Stehule wrote:
> fresh rebase

Hello,

Sorry, I haven't been following this thread, but I'd like to report a 
memory management bug. I couldn't apply the latest patches, so I tested 
with v20221104-1-* patches applied atop of commit b0284bfb1db.


postgres=# create variable s text default 'abc';

create function f() returns text as $$
begin
         return g(s);
end;
$$ language plpgsql;

create function g(t text) returns text as $$
begin
         let s = 'BOOM!';
         return t;
end;
$$ language plpgsql;

select f();
CREATE VARIABLE
CREATE FUNCTION
CREATE FUNCTION
server closed the connection unexpectedly
	This probably means the server terminated abnormally
	before or while processing the request.

LOG:  server process (PID 55307) was terminated by signal 11: 
Segmentation fault
DETAIL:  Failed process was running: select f();


I believe it's a use-after-free error, triggered by assigning a new 
value to s in g(), thus making t a dangling pointer.

After reconnecting I get a scary error:

postgres=# select f();
ERROR:  compressed pglz data is corrupt


Best regards,

-- 
Sergey Shinderuk		https://postgrespro.com/