[JENKINS-68562] Fix Git checkouts for controllers running on Windows

src/main/java/hudson/plugins/git/GitSCM.java

@@ -78,6 +78,7 @@
 import java.io.Serializable;
 import java.io.Writer;
 import java.nio.file.Files;
+import java.nio.file.InvalidPathException;
 import java.nio.file.Paths;
 import java.text.MessageFormat;
 import java.util.AbstractList;
@@ -1393,17 +1394,32 @@ public void checkout(Run<?, ?> build, Launcher launcher, FilePath workspace, Tas
         }
     }
 
-    private void abortIfSourceIsLocal() throws AbortException {
+    /* Package protected for test access */
+    void abortIfSourceIsLocal() throws AbortException {
         for (UserRemoteConfig userRemoteConfig: getUserRemoteConfigs()) {
             String remoteUrl = userRemoteConfig.getUrl();
-            if (remoteUrl != null && (remoteUrl.toLowerCase(Locale.ENGLISH).startsWith("file://") || Files.exists(Paths.get(remoteUrl)))) {
+            if (!isRemoteUrlValid(remoteUrl)) {
                 throw new AbortException("Checkout of Git remote '" + remoteUrl + "' aborted because it references a local directory, " +
                         "which may be insecure. You can allow local checkouts anyway by setting the system property '" +
                         ALLOW_LOCAL_CHECKOUT_PROPERTY + "' to true.");
             }
         }
     }
 
+    private static boolean isRemoteUrlValid(String remoteUrl) {
+        if (remoteUrl == null) {
+            return true;
+        } else if (remoteUrl.toLowerCase(Locale.ENGLISH).startsWith("file://")) {
+            return false;
+        }
+        try {
+            // Check for local remotes with no protocol like /path/to/repo.git/
+            return !Files.exists(Paths.get(remoteUrl));
+        } catch (InvalidPathException e) {
+            return true;
+        }
+    }
+
     private void printCommitMessageToLog(TaskListener listener, GitClient git, final Build revToBuild)
             throws IOException {
         try {

src/test/java/hudson/plugins/git/GitSCMUnitTest.java

@@ -23,6 +23,7 @@
  */
 package hudson.plugins.git;
 
+import hudson.AbortException;
 import hudson.EnvVars;
 import static hudson.plugins.git.GitSCM.createRepoList;
 import hudson.plugins.git.browser.GitRepositoryBrowser;
@@ -43,6 +44,8 @@
 import org.junit.Test;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import org.jvnet.hudson.test.Issue;
 import static org.hamcrest.MatcherAssert.*;
 import static org.hamcrest.Matchers.*;
 
@@ -338,4 +341,17 @@ public void testSetDoGenerateSubmoduleConfigurations() {
         /* Confirms the passed value `true` is ignored */
         assertFalse(gitSCM.getDoGenerateSubmoduleConfigurations());
     }
+
+    @Issue("JENKINS-68562")
+    @Test
+    public void testAbortIfSourceIsLocal() {
+        GitSCM gitSCM = new GitSCM(createRepoList(repoURL, null),
+                Collections.singletonList(new BranchSpec("master")),
+                null, null, Collections.emptyList());
+        try {
+            gitSCM.abortIfSourceIsLocal();
+        } catch (AbortException e) {
+            fail("https remote URLs should always be valid");
+        }
+    }
 }