From b5ac492fac9034d91862292c26d3f30fb7997ef6 Mon Sep 17 00:00:00 2001
From: Chrysostomos Nanakos <chris@include.gr>
Date: Wed, 1 Jul 2026 22:52:53 +0300
Subject: [PATCH] fix(dht-proxy): read timeout to prevent slot exhaustion
 (#1484)

Signed-off-by: Chrysostomos Nanakos <chris@include.gr>
---
 storage/dht_proxy/handler.nim  | 19 ++++++++++++-------
 storage/dht_proxy/protocol.nim |  2 ++
 2 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/storage/dht_proxy/handler.nim b/storage/dht_proxy/handler.nim
index 20ed2d8b..b3a0a807 100644
--- a/storage/dht_proxy/handler.nim
+++ b/storage/dht_proxy/handler.nim
@@ -61,6 +61,18 @@ proc handleLookupRequest(
     self: DhtProxyProtocol, conn: Connection
 ) {.async: (raises: [CancelledError]).} =
   try:
+    let reqBytes =
+      try:
+        await conn.readLp(MaxLookupRequestBytes).wait(DhtProxyRequestReadTimeout)
+      except AsyncTimeoutError:
+        debug "DHT proxy request read timed out"
+        return
+
+    let req = LookupRequest.decode(reqBytes).valueOr:
+      warn "Failed to decode lookup request"
+      await conn.writeLp(LookupResponse(code: LookupCode.ErrDecodeFailed).encode())
+      return
+
     if self.inFlight >= self.maxInFlight:
       debug "DHT proxy at capacity, replying ErrTooBusy",
         inFlight = self.inFlight, max = self.maxInFlight
@@ -71,13 +83,6 @@ proc handleLookupRequest(
     defer:
       dec self.inFlight
 
-    let
-      reqBytes = await conn.readLp(MaxLookupRequestBytes)
-      req = LookupRequest.decode(reqBytes).valueOr:
-        warn "Failed to decode lookup request"
-        await conn.writeLp(LookupResponse(code: LookupCode.ErrDecodeFailed).encode())
-        return
-
     let resp =
       case req.queryType
       of FindProviders:
diff --git a/storage/dht_proxy/protocol.nim b/storage/dht_proxy/protocol.nim
index 74ad385d..90327c73 100644
--- a/storage/dht_proxy/protocol.nim
+++ b/storage/dht_proxy/protocol.nim
@@ -9,6 +9,7 @@
 
 {.push raises: [].}
 
+import pkg/chronos
 import pkg/libp2p/protobuf/minprotobuf
 import pkg/libp2p_mix
 import pkg/libp2p/routing_record
@@ -19,6 +20,7 @@ import ../logutils
 const DhtProxyCodec* = "/storage/dht-proxy/1.0.0"
 
 const DefaultMaxInFlightLookups* = 100
+const DhtProxyRequestReadTimeout* = 5.seconds
 
 let MaxLookupRequestBytes* = getMaxMessageSizeForCodec(DhtProxyCodec, 1).expect(
     "DhtProxyCodec framing leaves no room for a Sphinx forward payload"