From b5a66e7353ba65c11c5fc6a79b72213bde8dbe44 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 18 Feb 2021 22:38:55 -0500 Subject: [PATCH] Fix another ancient bug in parsing of BRE-mode regular expressions. While poking at the regex code, I happened to notice that the bug squashed in commit afcc8772e had a sibling: next() failed to return a specific value associated with the '}' token for a "\{m,n\}" quantifier when parsing in basic RE mode. Again, this could result in treating the quantifier as non-greedy, which it never should be in basic mode. For that to happen, the last character before "\}" that sets "nextvalue" would have to set it to zero, or it'd have to have accidentally been zero from the start. The failure can be provoked repeatably with, for example, a bound ending in digit "0". Like the previous patch, back-patch all the way. --- src/backend/regex/regc_lex.c | 2 +- src/test/modules/test_regex/expected/test_regex.out | 9 ++++++++- src/test/modules/test_regex/sql/test_regex.sql | 3 ++- 3 files changed, 11 insertions(+), 3 deletions(-) diff --git a/src/backend/regex/regc_lex.c b/src/backend/regex/regc_lex.c index ca2bce4831..1666453164 100644 --- a/src/backend/regex/regc_lex.c +++ b/src/backend/regex/regc_lex.c @@ -389,7 +389,7 @@ next(struct vars *v) { v->now++; INTOCON(L_BRE); - RET('}'); + RETV('}', 1); } else FAILW(REG_BADBR); diff --git a/src/test/modules/test_regex/expected/test_regex.out b/src/test/modules/test_regex/expected/test_regex.out index f01ca071d9..21282789c2 100644 --- a/src/test/modules/test_regex/expected/test_regex.out +++ b/src/test/modules/test_regex/expected/test_regex.out @@ -614,7 +614,7 @@ ERROR: invalid regular expression: quantifier operand invalid -- expectError 7.15 - a*+ BADRPT select * from test_regex('a*+', '', '-'); ERROR: invalid regular expression: quantifier operand invalid --- test for ancient brenext() bug; not currently in Tcl +-- tests for ancient brenext() bugs; not currently in Tcl select * from test_regex('.*b', 'aaabbb', 'b'); test_regex ------------ @@ -622,6 +622,13 @@ select * from test_regex('.*b', 'aaabbb', 'b'); {aaabbb} (2 rows) +select * from test_regex('.\{1,10\}', 'abcdef', 'bQ'); + test_regex +----------------- + {0,REG_UBOUNDS} + {abcdef} +(2 rows) + -- doing 8 "braces" -- expectMatch 8.1 NQ "a{0,1}" "" "" select * from test_regex('a{0,1}', '', 'NQ'); diff --git a/src/test/modules/test_regex/sql/test_regex.sql b/src/test/modules/test_regex/sql/test_regex.sql index ae7d6b43e4..31e947ee9c 100644 --- a/src/test/modules/test_regex/sql/test_regex.sql +++ b/src/test/modules/test_regex/sql/test_regex.sql @@ -214,8 +214,9 @@ select * from test_regex('a?*', '', '-'); select * from test_regex('a+*', '', '-'); -- expectError 7.15 - a*+ BADRPT select * from test_regex('a*+', '', '-'); --- test for ancient brenext() bug; not currently in Tcl +-- tests for ancient brenext() bugs; not currently in Tcl select * from test_regex('.*b', 'aaabbb', 'b'); +select * from test_regex('.\{1,10\}', 'abcdef', 'bQ'); -- doing 8 "braces"