Description
If one uses in a theme user.save() a user can fire this function very fast by often reloading a page.
It happens to me that my account becomes corrupted on the filesystem. The enc_password was removed. My username and settings vanishes from the theme. I was still logged in but with logging out I was doomed.
Steps to reproduce
I found it by the solenoid theme. There are additional user settings defined. solenoid_userprefs = True in wikiconfig enables these vars. You should backup your id file. Then login. You need 5 to 10 times fast reloading (shift reload) of a page to get your account broken.
Example
Component selection
- user.save
Details
MoinMoin Version
1.9
OS and Version
Python Version
Server Setup
Server Details
Language you are using the wiki in (set in the browser/UserPreferences)
Workaround
don't use user.save() on places where you can fire it very fast.
Discussion
Looks like we need locking here. Usually we use it in moin with form based data submission.
Could be solved by following patch. Does it harm to have tmp files in the users dir?
1 diff -r 172146fe48a2 MoinMoin/user.py
2 --- a/MoinMoin/user.py Tue May 11 23:08:11 2010 +0200
3 +++ b/MoinMoin/user.py Sun May 16 19:01:30 2010 +0200
4 @@ -19,12 +19,12 @@
5 @license: GNU GPL, see COPYING for details.
6 """
7
8 -import os, time, codecs, base64
9 +import os, time, codecs, base64, tempfile
10
11 from MoinMoin.support.python_compatibility import hash_new, hmac_new
12
13 from MoinMoin import config, caching, wikiutil, i18n, events
14 -from MoinMoin.util import timefuncs, random_string
15 +from MoinMoin.util import filesys, timefuncs, random_string
16 from MoinMoin.wikiutil import url_quote_plus
17
18
19 @@ -542,11 +542,8 @@
20 os.makedirs(user_dir)
21
22 self.last_saved = str(time.time())
23 -
24 - # !!! should write to a temp file here to avoid race conditions,
25 - # or even better, use locking
26 -
27 - data = codecs.open(self.__filename(), "w", config.charset)
28 + fd, _tmp_filename = tempfile.mkstemp('.tmp', self.__filename(), self._cfg.user_dir)
29 + data = codecs.open(_tmp_filename, "w", config.charset)
30 data.write("# Data saved '%s' for id '%s'\n" % (
31 time.strftime(self._cfg.datetime_fmt, time.localtime(time.time())),
32 self.id))
33 @@ -565,6 +562,7 @@
34 line = line.replace('\n', ' ').replace('\r', ' ') # no lineseps
35 data.write(line + '\n')
36 data.close()
37 + filesys.rename(_tmp_filename, self.__filename())
38
39 arena = 'user'
40 key = 'name2id'
Issues with patch:
don't use self.__filename() for prefix (it contains full path), just use default prefix
- for opening, try to use fd (already open file handle, you can use fdopen() to open a python file), not the filename
see also: http://paste.pocoo.org/show/221656/
Plan
- Priority:
- Assigned to:
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