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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2023-03-11 12:15:41 -0500 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2023-03-11 12:15:41 -0500 |
| commit | 1925ac281a238fab50e208548f98daffdaaa0896 (patch) | |
| tree | dcba116a9bd634b7b1c60b7c02c5b3c67124f7f1 /contrib/pg_trgm/sql | |
| parent | d66bb048c3130c7b7a4876fc9050291f9e4cad2b (diff) | |
| download | postgresql-1925ac281a238fab50e208548f98daffdaaa0896.tar.gz | |
Fix misbehavior in contrib/pg_trgm with an unsatisfiable regex.
If the regex compiler can see that a regex is unsatisfiable
(for example, '$foo') then it may emit an NFA having no arcs.
pg_trgm's packGraph function did the wrong thing in this case;
it would access off the end of a work array, and with bad luck
could produce a corrupted output data structure causing more
problems later. This could end with wrong answers or crashes
in queries using a pg_trgm GIN or GiST index with such a regex.
Fix by not trying to de-duplicate if there aren't at least 2 arcs.
Per bug #17830 from Alexander Lakhin. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/17830-57ff5f89bdb02b09@postgresql.org
Diffstat (limited to 'contrib/pg_trgm/sql')
| -rw-r--r-- | contrib/pg_trgm/sql/pg_word_trgm.sql | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/contrib/pg_trgm/sql/pg_word_trgm.sql b/contrib/pg_trgm/sql/pg_word_trgm.sql index d9fa1c55e5..d2ada49133 100644 --- a/contrib/pg_trgm/sql/pg_word_trgm.sql +++ b/contrib/pg_trgm/sql/pg_word_trgm.sql @@ -43,3 +43,6 @@ select t,word_similarity('Baykal',t) as sml from test_trgm2 where 'Baykal' <% t select t,word_similarity('Kabankala',t) as sml from test_trgm2 where 'Kabankala' <% t order by sml desc, t; select t,word_similarity('Baykal',t) as sml from test_trgm2 where t %> 'Baykal' order by sml desc, t; select t,word_similarity('Kabankala',t) as sml from test_trgm2 where t %> 'Kabankala' order by sml desc, t; + +-- test unsatisfiable pattern +select * from test_trgm2 where t ~ '.*$x'; |