Mercurial > hg
view .hgignore @ 35810:113a30b87716 stable
lazymanifest: avoid reading uninitialized memory
I got errors running tests with clang UBSAN [1] enabled. One of them is:
```
--- test-dirstate.t
+++ test-dirstate.t.err
@@ -85,9 +85,115 @@
$ echo "[extensions]" >> .hg/hgrc
$ echo "dirstateex=../dirstateexception.py" >> .hg/hgrc
$ hg up 0
- abort: simulated error while recording dirstateupdates
- [255]
+ mercurial/cext/manifest.c:781:13: runtime error: load of value 190, which is not a valid value for type 'bool'
+ #0 0x7f668a8cf748 in lazymanifest_diff mercurial/cext/manifest.c:781
+ #1 0x7f6692fc1dc4 in call_function Python-2.7.11/Python/ceval.c:4350
+ .......
+ SUMMARY: UndefinedBehaviorSanitizer: invalid-bool-load mercurial/cext/manifest.c:781:13 in
+ [1]
$ hg log -r . -T '{rev}\n'
1
$ hg status
- ? a
```
While the code is not technically wrong, but switching the condition would
make clang UBSAN happy. So let's do it.
The uninitialized memory could come from, for example, `lazymanifest_copy`
allocates `self->maxlines` items but only writes the first `self->lines`
items.
[1]: https://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html
Test Plan:
Run `test-dirstate.t` with UBSAN and it no longer reports the issue.
Differential Revision: https://phab.mercurial-scm.org/D1948
author | Jun Wu <quark@fb.com> |
---|---|
date | Tue, 30 Jan 2018 20:32:48 -0800 |
parents | 964212780daf |
children | 1335bbfb066f |
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syntax: glob *.elc *.tmp *.orig *.rej *~ *.mergebackup *.o *.so *.dll *.exe *.pyd *.pyc *.pyo *$py.class *.swp *.prof *.zip \#*\# .\#* tests/.coverage* tests/.testtimes* tests/.hypothesis tests/hypothesis-generated tests/annotated tests/exceptions tests/*.err tests/htmlcov build contrib/chg/chg contrib/hgsh/hgsh contrib/vagrant/.vagrant contrib/docker/debian-* contrib/docker/ubuntu-* dist packages doc/common.txt doc/*.[0-9] doc/*.[0-9].txt doc/*.[0-9].gendoc.txt doc/*.[0-9].{x,ht}ml MANIFEST MANIFEST.in patches mercurial/__modulepolicy__.py mercurial/__version__.py mercurial/hgpythonlib.h mercurial.egg-info .DS_Store tags cscope.* .idea/* .asv/* i18n/hg.pot locale/*/LC_MESSAGES/hg.mo hgext/__index__.py rust/target/ # Generated wheels wheelhouse/ syntax: regexp ^\.pc/ ^\.(pydev)?project # hackable windows distribution additions ^hg-python ^hg.py$