From: Jan Wolski <jan@wolski.fi>
Date: Sun, 15 May 2022 14:49:19 +0000 (+0300)
Subject: gh-89668: Optimize ZipFile file header processing algorithm to avoid unneeded IO... 
X-Git-Tag: v3.12.0a1~1540
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=26a162baef96d78656e189b2fa16fdcab7195730;p=thirdparty%2FPython%2Fcpython.git

gh-89668: Optimize ZipFile file header processing algorithm to avoid unneeded IO(gh-25966)
---

diff --git a/Lib/zipfile.py b/Lib/zipfile.py
index dc0201108432..9f4437526c91 100644
--- a/Lib/zipfile.py
+++ b/Lib/zipfile.py
@@ -1564,7 +1564,7 @@ class ZipFile:
 
             fname = zef_file.read(fheader[_FH_FILENAME_LENGTH])
             if fheader[_FH_EXTRA_FIELD_LENGTH]:
-                zef_file.read(fheader[_FH_EXTRA_FIELD_LENGTH])
+                zef_file.seek(fheader[_FH_EXTRA_FIELD_LENGTH], whence=1)
 
             if zinfo.flag_bits & _MASK_COMPRESSED_PATCH:
                 # Zip 2.7: compressed patched data