From 9386cde871c750464073772409615e90344b80e9 Mon Sep 17 00:00:00 2001
From: Thomas Eizinger <thomas@eizinger.io>
Date: Mon, 18 Nov 2024 16:15:36 +1100
Subject: [PATCH] Only set `segment_size` if it is different from the transmit
 length

---
 quinn-udp/src/unix.rs | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/quinn-udp/src/unix.rs b/quinn-udp/src/unix.rs
index 02acdf0e0..38b322e24 100644
--- a/quinn-udp/src/unix.rs
+++ b/quinn-udp/src/unix.rs
@@ -593,7 +593,12 @@ fn prepare_msg(
         encoder.push(libc::IPPROTO_IPV6, libc::IPV6_TCLASS, ecn);
     }
 
-    if let Some(segment_size) = transmit.segment_size {
+    // Only set the segment size if it is different from the size of the contents.
+    // Some network drivers don't like being told to do GSO even if there is effectively only a single segment.
+    if let Some(segment_size) = transmit
+        .segment_size
+        .filter(|segment_size| *segment_size != transmit.contents.len())
+    {
         gso::set_segment_size(&mut encoder, segment_size as u16);
     }