diff --git a/plugins/ChannelLogger/plugin.py b/plugins/ChannelLogger/plugin.py
index a05dc6f87..4a922d4e1 100644
--- a/plugins/ChannelLogger/plugin.py
+++ b/plugins/ChannelLogger/plugin.py
@@ -35,6 +35,7 @@ import time
 import supybot.conf as conf
 import supybot.world as world
 import supybot.ircdb as ircdb
+import supybot.utils as utils
 import supybot.irclib as irclib
 import supybot.utils.minisix as minisix
 import supybot.ircmsgs as ircmsgs
@@ -95,9 +96,10 @@ class ChannelLogger(callbacks.Plugin):
 
     def getLogName(self, channel):
         if self.registryValue('rotateLogs', channel):
-            return '%s.%s.log' % (channel, self.logNameTimestamp(channel))
+            name = '%s.%s.log' % (channel, self.logNameTimestamp(channel))
         else:
-            return '%s.log' % channel
+            name = '%s.log' % channel
+        return utils.file.sanitizeName(name)
 
     def getLogDir(self, irc, channel):
         channel = self.normalizeChannel(irc, channel)
diff --git a/plugins/ChannelLogger/test.py b/plugins/ChannelLogger/test.py
index eb4064567..2304e29e0 100644
--- a/plugins/ChannelLogger/test.py
+++ b/plugins/ChannelLogger/test.py
@@ -32,5 +32,13 @@ from supybot.test import *
 class ChannelLoggerTestCase(PluginTestCase):
     plugins = ('ChannelLogger',)
 
+    def testLogDir(self):
+        self.assertEqual(
+            self.irc.getCallback('ChannelLogger').getLogName('#foo'),
+            '#foo.log')
+        self.assertEqual(
+            self.irc.getCallback('ChannelLogger').getLogName('#f/../oo'),
+            '#f..oo.log')
+
 
 # vim:set shiftwidth=4 softtabstop=4 expandtab textwidth=79:
diff --git a/plugins/__init__.py b/plugins/__init__.py
index 284934bbf..8ceb01ffd 100644
--- a/plugins/__init__.py
+++ b/plugins/__init__.py
@@ -60,14 +60,15 @@ def DB(filename, types):
         def junk(*args, **kwargs):
             pass
         return junk
-    filename = conf.supybot.directories.data.dirize(filename)
     def MakeDB(*args, **kwargs):
         for type in conf.supybot.databases():
             # Can't do this because Python sucks.  Go ahead, try it!
             # filename = '.'.join([filename, type, 'db'])
             fn = '.'.join([filename, type, 'db'])
+            fn = utils.file.sanitizeName(fn)
+            path = conf.supybot.directories.data.dirize(fn)
             try:
-                return types[type](fn, *args, **kwargs)
+                return types[type](path, *args, **kwargs)
             except KeyError:
                 continue
         raise NoSuitableDatabase(types.keys())
@@ -78,11 +79,11 @@ def makeChannelFilename(filename, channel=None, dirname=None):
     filename = os.path.basename(filename)
     channelSpecific = conf.supybot.databases.plugins.channelSpecific
     channel = channelSpecific.getChannelLink(channel)
-    channel = ircutils.toLower(channel)
+    channel = utils.file.sanitizeName(ircutils.toLower(channel))
     if dirname is None:
         dirname = conf.supybot.directories.data.dirize(channel)
     if not os.path.exists(dirname):
-            os.makedirs(dirname)
+        os.makedirs(dirname)
     return os.path.join(dirname, filename)
 
 def getChannel(channel):
diff --git a/src/utils/file.py b/src/utils/file.py
index 34d74536b..c48c634ea 100644
--- a/src/utils/file.py
+++ b/src/utils/file.py
@@ -37,6 +37,16 @@ import os.path
 
 from . import crypt
 
+def sanitizeName(filename):
+    """Removes / from filenames and escapes them if they are '.' or '..'."""
+    filename = filename.replace('/', '')
+    if filename == '.':
+        return '_'
+    elif filename == '..':
+        return '__'
+    else:
+        return filename
+
 def contents(filename):
     with open(filename) as fd:
         return fd.read()
diff --git a/test/test_plugins.py b/test/test_plugins.py
index 04968b4d6..2bbcf2a1f 100644
--- a/test/test_plugins.py
+++ b/test/test_plugins.py
@@ -29,6 +29,22 @@
 ###
 
 from supybot.test import *
+import supybot.conf as conf
 
 import supybot.irclib as irclib
 import supybot.plugins as plugins
+
+class PluginsTestCase(SupyTestCase):
+    def testMakeChannelFilename(self):
+        self.assertEqual(
+            plugins.makeChannelFilename('dir', '#foo'),
+            conf.supybot.directories.data() + '/#foo/dir')
+        self.assertEqual(
+            plugins.makeChannelFilename('dir', '#f/../oo'),
+            conf.supybot.directories.data() + '/#f..oo/dir')
+        self.assertEqual(
+            plugins.makeChannelFilename('dir', '/./'),
+            conf.supybot.directories.data() + '/_/dir')
+        self.assertEqual(
+            plugins.makeChannelFilename('dir', '/../'),
+            conf.supybot.directories.data() + '/__/dir')
diff --git a/test/test_utils.py b/test/test_utils.py
index 1c1c00d17..1d511723d 100644
--- a/test/test_utils.py
+++ b/test/test_utils.py
@@ -504,6 +504,10 @@ class FileTest(SupyTestCase):
         self.failUnless(utils.file.mktemp())
         self.failUnless(utils.file.mktemp())
 
+    def testSanitizeName(self):
+        self.assertEqual(utils.file.sanitizeName('#foo'), '#foo')
+        self.assertEqual(utils.file.sanitizeName('#f/../oo'), '#f..oo')
+
 
 class NetTest(SupyTestCase):
     def testEmailRe(self):