database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-26 01:22:12 +03:00
Code Activity

Abandon the use of Perl's Safe.pm to enforce restrictions in plperl, as it is

Browse Source 
fundamentally insecure. Instead apply an opmask to the whole interpreter that
imposes restrictions on unsafe operations. These restrictions are much harder
to subvert than is Safe.pm, since there is no container to be broken out of.
Backported to release 7.4.

In releases 7.4, 8.0 and 8.1 this also includes the necessary backporting of
the two interpreters model for plperl and plperlu adopted in release 8.2.

In versions 8.0 and up, the use of Perl's POSIX module to undo its locale
mangling on Windows has become insecure with these changes, so it is
replaced by our own routine, which is also faster.

Nice side effects of the changes include that it is now possible to use perl's
"strict" pragma in a natural way in plperl, and that perl's $a and
$b variables now work as expected in sort routines, and that function
compilation is significantly faster.

Tim Bunce and Andrew Dunstan, with reviews from Alex Hunsaker and
Alexey Klyukin.

Security: CVE-2010-1169
This commit is contained in:
Andrew Dunstan
2010-05-13 16:39:43 +00:00
parent 2b61b3e507
commit 1f474d299d
14 changed files with 400 additions and 266 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
src/pl/plperl/sql/plperl.sql
View File

@ -368,7 +368,16 @@ DO $$
$$ LANGUAGE plperl;
-- check that restricted operations are rejected in a plperl DO block
DO $$ eval "1+1"; $$ LANGUAGE plperl;
DO $$ system("/nonesuch"); $$ LANGUAGE plperl;
DO $$ qx("/nonesuch"); $$ LANGUAGE plperl;
DO $$ open my $fh, "</nonesuch"; $$ LANGUAGE plperl;
-- check that eval is allowed and eval'd restricted ops are caught
DO $$ eval q{chdir '.'}; warn "Caught: $@"; $$ LANGUAGE plperl;
-- check that compiling do (dofile opcode) is allowed
-- but that executing it for a file not already loaded (via require) dies
DO $$ warn do "/dev/null"; $$ LANGUAGE plperl;
-- check that we can't "use" a module that's not been loaded already
-- compile-time error: "Unable to load blib.pm into plperl"