From: J. Nick Koston <nick@koston.org>
Date: Sun, 23 Jul 2023 04:07:14 +0000 (-0500)
Subject: gh-82500: Fix asyncio sendfile overflow on 32bit (#107056)
X-Git-Tag: v3.13.0a1~1272
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=9eeb4b485f4f9e13e5cb638e43a0baecb3ff4e86;p=thirdparty%2FPython%2Fcpython.git

gh-82500: Fix asyncio sendfile overflow on 32bit (#107056)
---

diff --git a/Lib/asyncio/unix_events.py b/Lib/asyncio/unix_events.py
index 17fb4d5f7646..a2680865ed96 100644
--- a/Lib/asyncio/unix_events.py
+++ b/Lib/asyncio/unix_events.py
@@ -394,6 +394,9 @@ class _UnixSelectorEventLoop(selector_events.BaseSelectorEventLoop):
                 fut.set_result(total_sent)
                 return
 
+        # On 32-bit architectures truncate to 1GiB to avoid OverflowError
+        blocksize = min(blocksize, sys.maxsize//2 + 1)
+
         try:
             sent = os.sendfile(fd, fileno, offset, blocksize)
         except (BlockingIOError, InterruptedError):
diff --git a/Misc/NEWS.d/next/Library/2023-07-22-16-44-58.gh-issue-82500.cQYoPj.rst b/Misc/NEWS.d/next/Library/2023-07-22-16-44-58.gh-issue-82500.cQYoPj.rst
new file mode 100644
index 000000000000..065394fd6ee7
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2023-07-22-16-44-58.gh-issue-82500.cQYoPj.rst
@@ -0,0 +1 @@
+Fix overflow on 32-bit systems with :mod:`asyncio` :func:`os.sendfile` implemention.