From 204a3e1384b94790bdd77ba8fb93477dcf8405e0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?ihc=E7=AB=A5=E9=9E=8B=40=E6=8F=90=E4=B8=8D=E8=B5=B7?=
 =?UTF-8?q?=E5=8A=B2?= <ihciah@gmail.com>
Date: Tue, 3 Feb 2026 09:03:45 +0000
Subject: [PATCH] fix: set error to Payload before dispatcher disconnect
 (#3068)

* fix: set error to Payload before dispatcher disconnect

* align behavior

---------

Co-authored-by: Yuki Okushi <huyuumi.dev@gmail.com>
---
 actix-http/CHANGES.md           |  3 ++
 actix-http/src/h1/dispatcher.rs |  1 +
 actix-http/tests/test_server.rs | 54 +++++++++++++++++++++++++++++++++
 3 files changed, 58 insertions(+)

diff --git a/actix-http/CHANGES.md b/actix-http/CHANGES.md
index 197370bdf..f052c6d22 100644
--- a/actix-http/CHANGES.md
+++ b/actix-http/CHANGES.md
@@ -3,6 +3,9 @@
 ## Unreleased
 
 - Minimum supported Rust version (MSRV) is now 1.88.
+- Fix truncated body ending without error when connection closed abnormally. [#3067]
+
+[#3067]: https://github.com/actix/actix-web/pull/3067
 
 ## 3.11.2
 
diff --git a/actix-http/src/h1/dispatcher.rs b/actix-http/src/h1/dispatcher.rs
index 03851d0fb..c59be2d50 100644
--- a/actix-http/src/h1/dispatcher.rs
+++ b/actix-http/src/h1/dispatcher.rs
@@ -1156,6 +1156,7 @@ where
                         let inner = inner.as_mut().project();
                         inner.flags.insert(Flags::READ_DISCONNECT);
                         if let Some(mut payload) = inner.payload.take() {
+                            payload.set_error(PayloadError::Incomplete(None));
                             payload.feed_eof();
                         }
                     };
diff --git a/actix-http/tests/test_server.rs b/actix-http/tests/test_server.rs
index aafcde19a..688fc9d0b 100644
--- a/actix-http/tests/test_server.rs
+++ b/actix-http/tests/test_server.rs
@@ -443,6 +443,60 @@ async fn content_length() {
     srv.stop().await;
 }
 
+#[actix_rt::test]
+async fn content_length_truncated() {
+    use tokio::io::{AsyncReadExt, AsyncWriteExt};
+
+    let mut srv = test_server(|| {
+        HttpService::build()
+            .h1(|mut req: Request| async move {
+                let expected_length: usize = req.uri().path()[1..].parse().unwrap();
+                let mut payload = req.take_payload();
+
+                let mut length = 0;
+                let mut seen_error = false;
+                while let Some(chunk) = payload.next().await {
+                    match chunk {
+                        Ok(b) => length += b.len(),
+                        Err(_) => {
+                            seen_error = true;
+                            break;
+                        }
+                    }
+                }
+                if seen_error {
+                    return Result::<_, Infallible>::Ok(Response::bad_request());
+                }
+
+                assert_eq!(length, expected_length, "length must match when no error");
+                Result::<_, Infallible>::Ok(Response::ok())
+            })
+            .tcp()
+    })
+    .await;
+
+    let addr = srv.addr();
+    let mut buf = [0; 12];
+
+    let mut conn = TcpStream::connect(&addr).await.unwrap();
+    conn.write_all(b"POST /10000 HTTP/1.1\r\nContent-Length: 10000\r\n\r\ndata_truncated")
+        .await
+        .unwrap();
+    conn.shutdown().await.unwrap();
+    conn.read_exact(&mut buf).await.unwrap();
+    assert_eq!(&buf, b"HTTP/1.1 400");
+
+    let mut conn = TcpStream::connect(&addr).await.unwrap();
+    conn.write_all(b"POST /4 HTTP/1.1\r\nContent-Length: 4\r\n\r\ndata")
+        .await
+        .unwrap();
+    conn.shutdown().await.unwrap();
+    conn.read_exact(&mut buf).await.unwrap();
+    assert_eq!(&buf, b"HTTP/1.1 200");
+
+    srv.stop().await;
+}
+
 #[actix_rt::test]
 async fn h1_headers() {
     let data = STR.repeat(10);