From dfdf4a44a984076ae8f1b04c7910baedfcfe14dc Mon Sep 17 00:00:00 2001
From: Adam Duke <adam.v.duke@gmail.com>
Date: Sun, 29 Dec 2024 21:08:34 -0500
Subject: [PATCH] propagate underlying buffer write errors

---
 buffer/buffer.go | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/buffer/buffer.go b/buffer/buffer.go
index 4c528228..694ecc1c 100644
--- a/buffer/buffer.go
+++ b/buffer/buffer.go
@@ -189,6 +189,12 @@ func (b *Buffer) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 			return
 		}
 
+		if bw.writeError != nil {
+			b.log.Error("vulcand/oxy/buffer: failed to copy response, err: %v", bw.writeError)
+			b.errHandler.ServeHTTP(w, req, bw.writeError)
+			return
+		}
+
 		var reader multibuf.MultiReader
 		if bw.expectBody(outReq) {
 			rdr, err := writer.Reader()
@@ -258,6 +264,7 @@ type bufferWriter struct {
 	buffer         multibuf.WriterOnce
 	responseWriter http.ResponseWriter
 	hijacked       bool
+	writeError     error
 	log            utils.Logger
 }
 
@@ -298,6 +305,7 @@ func (b *bufferWriter) Write(buf []byte) (int, error) {
 		// if the writer returns an error, the reverse proxy panics
 		b.log.Error("write: %v", err)
 		length = len(buf)
+		b.writeError = err
 	}
 	return length, nil
 }