| commit | a25b9085043b8029169b4d5b172b78ca3f38fb37 | [log] [tgz] |
|---|---|---|
| author | Ævar Arnfjörð Bjarmason <avarab@gmail.com> | Thu Nov 23 14:16:58 2017 +0000 |
| committer | Junio C Hamano <gitster@pobox.com> | Fri Nov 24 16:12:26 2017 +0900 |
| tree | 806946c9755062cb3a37f2c68f81429e01311ead | |
| parent | ce9a257031ca1cf3496c5bb1cd0d4b5ecb8379f2 [diff] |
grep: fix segfault under -P + PCRE2 <=10.30 + (*NO_JIT)
Fix a bug in the compilation of PCRE2 patterns under JIT (the most
common runtime configuration). Any pattern with a (*NO_JIT) verb would
segfault in any currently released PCRE2 version:
$ git grep -P '(*NO_JIT)hi.*there'
Segmentation fault
That this segfaulted was a bug in PCRE2 itself, after reporting it[1]
on pcre-dev it's been fixed in a yet-to-be-released version of
PCRE (presumably released first as 10.31). Now it'll die with:
$ git grep -P '(*NO_JIT)hi.*there'
fatal: pcre2_jit_match failed with error code -45: bad JIT option
But the cause of the bug is in our own code dating back to my
94da9193a6 ("grep: add support for PCRE v2", 2017-06-01).
As explained at more length in the comment being added here, it isn't
sufficient to just check pcre2_config() to see whether the JIT should
be used, pcre2_pattern_info() also has to be asked.
This is something I discovered myself when fiddling around with PCRE2
verbs in patterns passed to git. I don't expect that any user of git
has encountered this given the obscurity of passing PCRE2 verbs
through to the library, along with the relative obscurity of (*NO_JIT)
itself.
1. "How am I supposed to use PCRE2 JIT in the face of (*NO_JIT) ?"
(<CACBZZX5mMqDuWuFmi7sRBp3wH6CFyd-ghACukd=v0NN=rBMnJg@mail.gmail.com> &
https://lists.exim.org/lurker/thread/20171123.101502.7f0d38ca.en.html)
on the pcre-dev mailing list
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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