fix: codeql user value provided path validation

server/routes/git.js

@@ -61,10 +61,19 @@ function validateBranchName(branch) {
   return branch;
 }
 
-function validateFilePath(file) {
+function validateFilePath(file, projectPath) {
   if (!file || file.includes('\0')) {
     throw new Error('Invalid file path');
   }
+  // Prevent path traversal: resolve the file relative to the project root
+  // and ensure the result stays within the project directory
+  if (projectPath) {
+    const resolved = path.resolve(projectPath, file);
+    const normalizedRoot = path.resolve(projectPath) + path.sep;
+    if (!resolved.startsWith(normalizedRoot) && resolved !== path.resolve(projectPath)) {
+      throw new Error('Invalid file path: path traversal detected');
+    }
+  }
   return file;
 }
 
@@ -75,15 +84,33 @@ function validateRemoteName(remote) {
   return remote;
 }
 
+function validateProjectPath(projectPath) {
+  if (!projectPath || projectPath.includes('\0')) {
+    throw new Error('Invalid project path');
+  }
+  const resolved = path.resolve(projectPath);
+  // Must be an absolute path after resolution
+  if (!path.isAbsolute(resolved)) {
+    throw new Error('Invalid project path: must be absolute');
+  }
+  // Block obviously dangerous paths
+  if (resolved === '/' || resolved === path.sep) {
+    throw new Error('Invalid project path: root directory not allowed');
+  }
+  return resolved;
+}
+
 // Helper function to get the actual project path from the encoded project name
 async function getActualProjectPath(projectName) {
+  let projectPath;
   try {
-    return await extractProjectDirectory(projectName);
+    projectPath = await extractProjectDirectory(projectName);
   } catch (error) {
     console.error(`Error extracting project directory for ${projectName}:`, error);
     // Fallback to the old method
-    return projectName.replace(/-/g, '/');
+    projectPath = projectName.replace(/-/g, '/');
   }
+  return validateProjectPath(projectPath);
 }
 
 // Helper function to strip git diff headers
@@ -230,7 +257,7 @@ router.get('/diff', async (req, res) => {
     await validateGitRepository(projectPath);
     
     // Validate file path
-    validateFilePath(file);
+    validateFilePath(file, projectPath);
 
     // Check if file is untracked or deleted
     const { stdout: statusOutput } = await spawnAsync('git', ['status', '--porcelain', file], { cwd: projectPath });
@@ -295,7 +322,7 @@ router.get('/file-with-diff', async (req, res) => {
     await validateGitRepository(projectPath);
 
     // Validate file path
-    validateFilePath(file);
+    validateFilePath(file, projectPath);
 
     // Check file status
     const { stdout: statusOutput } = await spawnAsync('git', ['status', '--porcelain', file], { cwd: projectPath });
@@ -406,7 +433,7 @@ router.post('/commit', async (req, res) => {
     
     // Stage selected files
     for (const file of files) {
-      validateFilePath(file);
+      validateFilePath(file, projectPath);
       await spawnAsync('git', ['add', file], { cwd: projectPath });
     }
 
@@ -610,7 +637,7 @@ router.post('/generate-commit-message', async (req, res) => {
     let diffContext = '';
     for (const file of files) {
       try {
-        validateFilePath(file);
+        validateFilePath(file, projectPath);
         const { stdout } = await spawnAsync(
           'git', ['diff', 'HEAD', '--', file],
           { cwd: projectPath }
@@ -1139,7 +1166,7 @@ router.post('/discard', async (req, res) => {
     await validateGitRepository(projectPath);
 
     // Validate file path
-    validateFilePath(file);
+    validateFilePath(file, projectPath);
 
     // Check file status to determine correct discard command
     const { stdout: statusOutput } = await spawnAsync('git', ['status', '--porcelain', file], { cwd: projectPath });
@@ -1188,7 +1215,7 @@ router.post('/delete-untracked', async (req, res) => {
     await validateGitRepository(projectPath);
 
     // Validate file path
-    validateFilePath(file);
+    validateFilePath(file, projectPath);
 
     // Check if file is actually untracked
     const { stdout: statusOutput } = await spawnAsync('git', ['status', '--porcelain', file], { cwd: projectPath });