From 75aa29cd682c7df48be8d031287f92dcba575770 Mon Sep 17 00:00:00 2001
From: Nick Bolton <nick@symless.com>
Date: Tue, 28 Apr 2026 12:22:06 +0100
Subject: [PATCH 1/2] docs: update collaboration notes with working style and
 GitHub Actions guidelines

---
 CLAUDE.md | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/CLAUDE.md b/CLAUDE.md
index 96fe80d1e..0f05c431a 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -1,5 +1,13 @@
 # Synergy — collaboration notes
 
+## Working style
+
+- **Never configure or build unless explicitly asked.** No `cmake`, `cmake --build`, `make`, `ninja`, etc. After code changes, stop at the edit and ask the user to build manually.
+
+## GitHub Actions
+
+- `matrix` context is NOT available in job-level `if` — the `if` runs before the matrix is expanded. Use step-level `if` conditions instead (e.g. set a `skip` output in a setup step and check it per-step).
+
 ## Code style
 
 - Default to **no comments**. Only add one when the WHY is non-obvious — hidden constraints, subtle invariants, workarounds for specific bugs, behavior that would surprise a reader. Never add comments that explain WHAT or HOW (well-named identifiers do that).

From 3d0ea11ef520a4cc5b6613924fc998df9ef823b4 Mon Sep 17 00:00:00 2001
From: Nick Bolton <nick@symless.com>
Date: Tue, 28 Apr 2026 12:23:11 +0100
Subject: [PATCH 2/2] fix: add error handling for truncated clipboard data in
 unmarshall function

---
 src/lib/deskflow/IClipboard.cpp | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/lib/deskflow/IClipboard.cpp b/src/lib/deskflow/IClipboard.cpp
index 02a044d5b..f0e7ee6e3 100644
--- a/src/lib/deskflow/IClipboard.cpp
+++ b/src/lib/deskflow/IClipboard.cpp
@@ -17,6 +17,7 @@
  */
 
 #include "deskflow/IClipboard.h"
+#include "base/Log.h"
 #include "common/stdvector.h"
 
 //
@@ -28,6 +29,7 @@ void IClipboard::unmarshall(IClipboard *clipboard, const String &data, Time time
   assert(clipboard != NULL);
 
   const char *index = data.data();
+  const char *const end = index + data.size();
 
   if (clipboard->open(time)) {
     // clear existing data
@@ -35,10 +37,20 @@ void IClipboard::unmarshall(IClipboard *clipboard, const String &data, Time time
 
     // read the number of formats
     const UInt32 numFormats = readUInt32(index);
+    if (end - index < 4) {
+      LOG_ERR("clipboard unmarshall: truncated header");
+      clipboard->close();
+      return;
+    }
     index += 4;
 
     // read each format
     for (UInt32 i = 0; i < numFormats; ++i) {
+      // need 8 bytes for format id + payload size
+      if (end - index < 8) {
+        LOG_ERR("clipboard unmarshall: truncated format header at %u/%u", i, numFormats);
+        break;
+      }
       // get the format id
       IClipboard::EFormat format = static_cast<IClipboard::EFormat>(readUInt32(index));
       index += 4;
@@ -47,6 +59,12 @@ void IClipboard::unmarshall(IClipboard *clipboard, const String &data, Time time
       UInt32 size = readUInt32(index);
       index += 4;
 
+      // peer-supplied size must not exceed remaining buffer
+      if (size > static_cast<UInt32>(end - index)) {
+        LOG_ERR("clipboard unmarshall: payload size %u exceeds remaining %zd", size, end - index);
+        break;
+      }
+
       // save the data if it's a known format.  if either the client
       // or server supports more clipboard formats than the other
       // then one of them will get a format >= kNumFormats here.