57 lines
2.4 KiB
Diff
57 lines
2.4 KiB
Diff
From f4cd5e29bc15621f2ab8fc5d7de0e68e62d43999 Mon Sep 17 00:00:00 2001
|
|
From: Hugo van der Sanden <hv@crypt.org>
|
|
Date: Tue, 15 Sep 2020 14:02:54 +0100
|
|
Subject: [PATCH] [gh18096] assume worst-case for GOSUBs we don't analyse
|
|
MIME-Version: 1.0
|
|
Content-Type: text/plain; charset=UTF-8
|
|
Content-Transfer-Encoding: 8bit
|
|
|
|
During study_chunk, under various conditions we avoid recursing into
|
|
a GOSUB. But we must avoid giving the enclosing scope the idea that
|
|
this GOSUB would match only an empty string, since that could trigger
|
|
wrong optimizations (eg CURLYX => CURLYM in the ticket).
|
|
|
|
So we mark the construct as infinite, as in the code branch where we
|
|
_do_ recurse into it.
|
|
|
|
Signed-off-by: Petr Písař <ppisar@redhat.com>
|
|
---
|
|
regcomp.c | 7 ++++++-
|
|
t/re/re_tests | 2 ++
|
|
2 files changed, 8 insertions(+), 1 deletion(-)
|
|
|
|
diff --git a/regcomp.c b/regcomp.c
|
|
index 124ea5b90b..fae3f8079d 100644
|
|
--- a/regcomp.c
|
|
+++ b/regcomp.c
|
|
@@ -5212,7 +5212,12 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
|
|
* might result in a minlen of 1 and not of 4,
|
|
* but this doesn't make us mismatch, just try a bit
|
|
* harder than we should.
|
|
- * */
|
|
+ *
|
|
+ * However we must assume this GOSUB is infinite, to
|
|
+ * avoid wrongly applying other optimizations in the
|
|
+ * enclosing scope - see GH 18096, for example.
|
|
+ */
|
|
+ is_inf = is_inf_internal = 1;
|
|
scan= regnext(scan);
|
|
continue;
|
|
}
|
|
diff --git a/t/re/re_tests b/t/re/re_tests
|
|
index 554a7004a2..ab5a0d8012 100644
|
|
--- a/t/re/re_tests
|
|
+++ b/t/re/re_tests
|
|
@@ -2023,6 +2023,8 @@ AB\s+\x{100} AB \x{100}X y - -
|
|
/(?iaax:A? \K +)/ African_Feh c - \\K + is forbidden - matches null string many times in regex
|
|
/(?iaa:A?\K+)/ African_Feh c - \\K+ is forbidden - matches null string many times in regex
|
|
/(?iaa:A?\K*)/ African_Feh c - \\K* is forbidden - matches null string many times in regex
|
|
+^((\w|<(\s)*(?1)(?3)*>)(?:(?3)*\+(?3)*(?2))*)(?3)*\+ a + b + <c + d> y $1 a + b # [GH #18096]
|
|
+^((\w|<(\s)*(?1)(?3)*>)(?:(?3)*\+(?3)*(?2))*)(?3)*\+ a + <b> + c y $1 a + <b> # [GH #18096]
|
|
# Keep these lines at the end of the file
|
|
# pat string y/n/etc expr expected-expr skip-reason comment
|
|
# vim: softtabstop=0 noexpandtab
|
|
--
|
|
2.25.4
|
|
|