293 Backport for Container Escaping fix (#2133)

* Fix escaping of docker envs backport * create as prerelease * add release number Co-authored-by: Nikola Jokic <[email protected]>
actions · Sep 20, 2022 · 1501917 · 1501917
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commit 1501917
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diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
@@ -89,7 +89,7 @@ jobs:
         - runtime: osx-x64
           os: macOS-latest
           devScript: ./dev.sh
-        
+
         - runtime: osx-arm64
           os: macOS-latest
           devScript: ./dev.sh
@@ -158,7 +158,7 @@ jobs:
       id: sha_noruntime_noexternals
       name: Compute SHA256
       working-directory: _package_trims/trim_runtime_externals
-    
+
     - name: Create trimmedpackages.json for ${{ matrix.runtime }}
       if: matrix.runtime == 'win-x64'
       uses: actions/[email protected]
@@ -288,6 +288,7 @@ jobs:
         release_name: "v${{ steps.releaseNote.outputs.version }}"
         body: |
           ${{ steps.releaseNote.outputs.note }}
+        prerelease: true
 
     # Upload release assets (full runner packages)
     - name: Upload Release Asset (win-x64)

diff --git a/releaseNote.md b/releaseNote.md
@@ -1,11 +1,8 @@
 ## Features
-- Allow self-hosted runner admins to fail jobs that don't have a job container (#1895)
-- Experimental: Self-hosted runner admins can now use scripts to customize the container invocation in the runner (#1853)
 ## Bugs
-- Fixed an issue where a Job Hook would fail to execute if the shell path contains a space on Windows (#1826)
+- Fixed an issue where container environment variables names or values could escape the docker command (#2108)
 
 ## Misc
-- Handle new `HostedRunnerShutdownMessage` to shutdown hosted runners faster (#1922)
 
 ## Windows x64
 We recommend configuring the runner in a root folder of the Windows drive (e.g. "C:\actions-runner"). This will help avoid issues related to service identity folder permissions and long file path restrictions on Windows.

diff --git a/src/Runner.Worker/Container/DockerCommandManager.cs b/src/Runner.Worker/Container/DockerCommandManager.cs
@@ -131,11 +131,11 @@ public async Task<string> DockerCreate(IExecutionContext context, ContainerInfo
             {
                 if (String.IsNullOrEmpty(env.Value))
                 {
-                    dockerOptions.Add($"-e \"{env.Key}\"");
+                    dockerOptions.Add(DockerUtil.CreateEscapedOption("-e", env.Key));
                 }
                 else
                 {
-                    dockerOptions.Add($"-e \"{env.Key}={env.Value.Replace("\"", "\\\"")}\"");
+                    dockerOptions.Add(DockerUtil.CreateEscapedOption("-e", env.Key, env.Value));
                 }
             }
 
@@ -202,7 +202,7 @@ public async Task<int> DockerRun(IExecutionContext context, ContainerInfo contai
             {
                 // e.g. -e MY_SECRET maps the value into the exec'ed process without exposing
                 // the value directly in the command
-                dockerOptions.Add($"-e {env.Key}");
+                dockerOptions.Add(DockerUtil.CreateEscapedOption("-e", env.Key));
             }
 
             // Watermark for GitHub Action environment

diff --git a/src/Runner.Worker/Container/DockerUtil.cs b/src/Runner.Worker/Container/DockerUtil.cs
@@ -6,6 +6,9 @@ namespace GitHub.Runner.Worker.Container
 {
     public class DockerUtil
     {
+        private static readonly Regex QuoteEscape = new Regex(@"(\\*)" + "\"", RegexOptions.Compiled);
+        private static readonly Regex EndOfStringEscape = new Regex(@"(\\+)$", RegexOptions.Compiled);
+
         public static List<PortMapping> ParseDockerPort(IList<string> portMappingLines)
         {
             const string targetPort = "targetPort";
@@ -17,7 +20,7 @@ public static List<PortMapping> ParseDockerPort(IList<string> portMappingLines)
             string pattern = $"^(?<{targetPort}>\\d+)/(?<{proto}>\\w+) -> (?<{host}>.+):(?<{hostPort}>\\d+)$";
 
             List<PortMapping> portMappings = new List<PortMapping>();
-            foreach(var line in portMappingLines)
+            foreach (var line in portMappingLines)
             {
                 Match m = Regex.Match(line, pattern, RegexOptions.None, TimeSpan.FromSeconds(1));
                 if (m.Success)
@@ -61,5 +64,44 @@ public static string ParseRegistryHostnameFromImageName(string name)
             }
             return "";
         }
+
+        public static string CreateEscapedOption(string flag, string key)
+        {
+            if (String.IsNullOrEmpty(key))
+            {
+                return "";
+            }
+            return $"{flag} {EscapeString(key)}";
+        }
+
+        public static string CreateEscapedOption(string flag, string key, string value)
+        {
+            if (String.IsNullOrEmpty(key))
+            {
+                return "";
+            }
+            var escapedString = EscapeString($"{key}={value}");
+            return $"{flag} {escapedString}";
+        }
+
+        private static string EscapeString(string value)
+        {
+            if (String.IsNullOrEmpty(value))
+            {
+                return "";
+            }
+            // Dotnet escaping rules are weird here, we can only escape \ if it precedes a "
+            // If a double quotation mark follows two or an even number of backslashes, each proceeding backslash pair is replaced with one backslash and the double quotation mark is removed.
+            // If a double quotation mark follows an odd number of backslashes, including just one, each preceding pair is replaced with one backslash and the remaining backslash is removed; however, in this case the double quotation mark is not removed.
+            // https://docs.microsoft.com/en-us/dotnet/api/system.environment.getcommandlineargs?redirectedfrom=MSDN&view=net-6.0#remarks
+
+            // First, find any \ followed by a " and double the number of \ + 1.
+             value = QuoteEscape.Replace(value, @"$1$1\" + "\"");
+            // Next, what if it ends in `\`, it would escape the end quote. So, we need to detect that at the end of the string and perform the same escape
+            // Luckily, we can just use the $ character with detects the end of string in regex
+            value = EndOfStringEscape.Replace(value, @"$1$1");
+            // Finally, wrap it in quotes
+            return $"\"{value}\"";
+        }
     }
 }
diff --git a/src/Runner.Worker/Handlers/StepHost.cs b/src/Runner.Worker/Handlers/StepHost.cs
@@ -193,7 +193,7 @@ public async Task<int> ExecuteAsync(IExecutionContext context,
                 TranslateToContainerPath(environment);
                 await containerHookManager.RunScriptStepAsync(context,
                                                                                    Container,
-                                                                                   workingDirectory,                                                                                   
+                                                                                   workingDirectory,
                                                                                    fileName,
                                                                                    arguments,
                                                                                    environment,
@@ -216,7 +216,7 @@ await containerHookManager.RunScriptStepAsync(context,
             {
                 // e.g. -e MY_SECRET maps the value into the exec'ed process without exposing
                 // the value directly in the command
-                dockerCommandArgs.Add($"-e {env.Key}");
+                dockerCommandArgs.Add(DockerUtil.CreateEscapedOption("-e", env.Key));
             }
             if (!string.IsNullOrEmpty(PrependPath))
             {

diff --git a/src/Test/L0/Container/DockerUtilL0.cs b/src/Test/L0/Container/DockerUtilL0.cs
@@ -144,5 +144,54 @@ public void ParseRegistryHostnameFromImageName(string input, string expected)
             var actual = DockerUtil.ParseRegistryHostnameFromImageName(input);
             Assert.Equal(expected, actual);
         }
+
+        [Theory]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        [InlineData("", "")]
+        [InlineData("foo", "foo")]
+        [InlineData("foo \\ bar", "foo \\ bar")]
+        [InlineData("foo \\", "foo \\\\")]
+        [InlineData("foo \\\\", "foo \\\\\\\\")]
+        [InlineData("foo \\\" bar", "foo \\\\\\\" bar")]
+        [InlineData("foo \\\\\" bar", "foo \\\\\\\\\\\" bar")]
+        public void CreateEscapedOption_keyOnly(string input, string escaped)
+        {
+            var flag = "--example";
+            var actual = DockerUtil.CreateEscapedOption(flag, input);
+            string expected;
+            if (String.IsNullOrEmpty(input))
+            {
+                expected = "";
+            }
+            else
+            {
+                expected = $"{flag} \"{escaped}\"";
+            }
+            Assert.Equal(expected, actual);
+        }
+
+        [Theory]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        [InlineData("foo", "bar", "foo=bar")]
+        [InlineData("foo\\", "bar", "foo\\=bar")]
+        [InlineData("foo\\", "bar\\", "foo\\=bar\\\\")]
+        [InlineData("foo \\","bar \\", "foo \\=bar \\\\")]
+        public void CreateEscapedOption_keyValue(string keyInput, string valueInput, string escapedString)
+        {
+            var flag = "--example";
+            var actual = DockerUtil.CreateEscapedOption(flag, keyInput, valueInput);
+            string expected;
+            if (String.IsNullOrEmpty(keyInput))
+            {
+                expected = "";
+            }
+            else
+            {
+                expected = $"{flag} \"{escapedString}\"";
+            }
+            Assert.Equal(expected, actual);
+        }
     }
 }
diff --git a/src/runnerversion b/src/runnerversion
@@ -1 +1 @@
-2.293.0
+2.293.1