From fa6fe432075df5e0eceb1ccd85038159cc820ccc Mon Sep 17 00:00:00 2001
From: MarcoFalke <*~=`'#}+{/-|&$^_@721217.xyz>
Date: Fri, 9 Aug 2024 13:43:36 +0200
Subject: [PATCH] net: Clarify that m_addr_local is only set once

Includes a rename from addrLocal to m_addr_local to match the name of
its corresponding Mutex.
---
 src/net.cpp           |  8 +++-----
 src/net.h             |  2 +-
 src/test/fuzz/net.cpp | 12 +++++-------
 3 files changed, 9 insertions(+), 13 deletions(-)

diff --git a/src/net.cpp b/src/net.cpp
index acd78a3505a84..e1206745a425d 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -576,16 +576,14 @@ CService CNode::GetAddrLocal() const
 {
     AssertLockNotHeld(m_addr_local_mutex);
     LOCK(m_addr_local_mutex);
-    return addrLocal;
+    return m_addr_local;
 }
 
 void CNode::SetAddrLocal(const CService& addrLocalIn) {
     AssertLockNotHeld(m_addr_local_mutex);
     LOCK(m_addr_local_mutex);
-    if (addrLocal.IsValid()) {
-        LogError("Addr local already set for node: %i. Refusing to change from %s to %s\n", id, addrLocal.ToStringAddrPort(), addrLocalIn.ToStringAddrPort());
-    } else {
-        addrLocal = addrLocalIn;
+    if (Assume(!m_addr_local.IsValid())) { // Addr local can only be set once during version msg processing
+        m_addr_local = addrLocalIn;
     }
 }
 
diff --git a/src/net.h b/src/net.h
index 8449a90b72237..beec58c389872 100644
--- a/src/net.h
+++ b/src/net.h
@@ -963,7 +963,7 @@ class CNode
     size_t m_msg_process_queue_size GUARDED_BY(m_msg_process_queue_mutex){0};
 
     // Our address, as reported by the peer
-    CService addrLocal GUARDED_BY(m_addr_local_mutex);
+    CService m_addr_local GUARDED_BY(m_addr_local_mutex);
     mutable Mutex m_addr_local_mutex;
 
     mapMsgTypeSize mapSendBytesPerMsgType GUARDED_BY(cs_vSend);
diff --git a/src/test/fuzz/net.cpp b/src/test/fuzz/net.cpp
index e8b1480c5b04c..4cec96274e7a2 100644
--- a/src/test/fuzz/net.cpp
+++ b/src/test/fuzz/net.cpp
@@ -33,6 +33,11 @@ FUZZ_TARGET(net, .init = initialize_net)
     SetMockTime(ConsumeTime(fuzzed_data_provider));
     CNode node{ConsumeNode(fuzzed_data_provider)};
     node.SetCommonVersion(fuzzed_data_provider.ConsumeIntegral<int>());
+    if (const auto service_opt =
+            ConsumeDeserializable<CService>(fuzzed_data_provider, ConsumeDeserializationParams<CNetAddr::SerParams>(fuzzed_data_provider)))
+    {
+        node.SetAddrLocal(*service_opt);
+    }
     LIMITED_WHILE(fuzzed_data_provider.ConsumeBool(), 10000) {
         CallOneOf(
             fuzzed_data_provider,
@@ -52,13 +57,6 @@ FUZZ_TARGET(net, .init = initialize_net)
                     node.Release();
                 }
             },
-            [&] {
-                const std::optional<CService> service_opt = ConsumeDeserializable<CService>(fuzzed_data_provider, ConsumeDeserializationParams<CNetAddr::SerParams>(fuzzed_data_provider));
-                if (!service_opt) {
-                    return;
-                }
-                node.SetAddrLocal(*service_opt);
-            },
             [&] {
                 const std::vector<uint8_t> b = ConsumeRandomLengthByteVector(fuzzed_data_provider);
                 bool complete;