Bug #1413790: zipfile now sanitizes absolute archive names that are

not allowed by the specs.

Doc/lib/libzipfile.tex

@@ -140,10 +140,13 @@ cat myzip.zip >> python.exe
                           compress_type}}}
   Write the file named \var{filename} to the archive, giving it the
   archive name \var{arcname} (by default, this will be the same as
-  \var{filename}).  If given, \var{compress_type} overrides the value
+  \var{filename}, but without a drive letter and with leading path
+  separators removed).  If given, \var{compress_type} overrides the value
   given for the \var{compression} parameter to the constructor for
   the new entry.  The archive must be open with mode \code{'w'} or
   \code{'a'}.
+  \note{Archive names should be relative to the archive root, that is,
+        they should not start with a path separator.}
 \end{methoddesc}
 
 \begin{methoddesc}{writestr}{zinfo_or_arcname, bytes}

Lib/test/test_zipfile.py

@@ -45,6 +45,16 @@ class TestsWithSourceFile(unittest.TestCase):
             for f in (TESTFN2, TemporaryFile(), StringIO()):
                 self.zipTest(f, zipfile.ZIP_DEFLATED)
 
+    def testAbsoluteArcnames(self):
+        zipfp = zipfile.ZipFile(TESTFN2, "w", zipfile.ZIP_STORED)
+        zipfp.write(TESTFN, "/absolute")
+        zipfp.close()
+
+        zipfp = zipfile.ZipFile(TESTFN2, "r", zipfile.ZIP_STORED)
+        self.assertEqual(zipfp.namelist(), ["absolute"])
+        zipfp.close()
+        
+
     def tearDown(self):
         os.remove(TESTFN)
         os.remove(TESTFN2)

Lib/zipfile.py

@@ -397,8 +397,10 @@ class ZipFile:
         date_time = mtime[0:6]
         # Create ZipInfo instance to store file information
         if arcname is None:
-            zinfo = ZipInfo(filename, date_time)
+            arcname = filename
-        else:
+        arcname = os.path.normpath(os.path.splitdrive(arcname)[1])
+        while arcname[0] in (os.sep, os.altsep):
+            arcname = arcname[1:]
         zinfo = ZipInfo(arcname, date_time)
         zinfo.external_attr = (st[0] & 0xFFFF) << 16L      # Unix attributes
         if compress_type is None:

Misc/NEWS

@@ -372,6 +372,12 @@ Extension Modules
 Library
 -------
 
+- Bug #1413790: zipfile now sanitizes absolute archive names that are
+  not allowed by the specs.
+
+- Bug #1413790: zipfile now sanitizes absolute archive names that are
+  not allowed by the specs.
+
 - Patch #1215184: FileInput now can be given an opening hook which can
   be used to control how files are opened.