[no-relnote] Add e2e test for firmware path traversal

A container image could be crafted with a symbolic link in
/lib/firmware/nvidia/ that points to a location outside of the
container's root filesystem. When running such a container with the
NVIDIA Container Toolkit, this could potentially lead to files being
created on the host filesystem.

This change adds an end-to-end test to ensure that the toolkit is not
vulnerable to this kind of path traversal attack.

Signed-off-by: Carlos Eduardo Arango Gutierrez <[email protected]>

Author: ArangoGutierrez

tests/e2e/nvidia-container-toolkit_test.go

@@ -18,6 +18,7 @@ package e2e
 
 import (
 	"context"
+	"fmt"
 	"path/filepath"
 	"strings"
 
@@ -297,4 +298,54 @@ var _ = Describe("docker", Ordered, ContinueOnFailure, func() {
 			Expect(err).ToNot(HaveOccurred())
 		})
 	})
+
+	When("Running a container where the firmware folder resolves outside the container root", Ordered, func() {
+		var outputDir string
+		BeforeAll(func(ctx context.Context) {
+			pwd, _, err := runner.Run("pwd")
+			Expect(err).ToNot(HaveOccurred())
+			outputDir = filepath.Join(strings.TrimSpace(pwd), "test-output")
+
+			_, _, err = runner.Run(fmt.Sprintf("mkdir -p %s", outputDir))
+			Expect(err).ToNot(HaveOccurred())
+
+			_, _, err = runner.Run("docker pull ubuntu")
+			Expect(err).ToNot(HaveOccurred())
+
+			dockerBuildCmd := fmt.Sprintf(`docker build -t firmware-test --build-arg RM_VERSION="$(basename $(ls -d /lib/firmware/nvidia/*.*))" --build-arg CURRENT_DIR=%q - <<EOF`, outputDir)
+			dockerBuildDockerfile := `
+FROM ubuntu
+RUN mkdir -p /lib/firmware/nvidia/
+ARG RM_VERSION
+ARG CURRENT_DIR
+RUN ln -s /../../../../../../../../\$CURRENT_DIR /lib/firmware/nvidia/\$RM_VERSION
+EOF`
+			_, _, err = runner.Run(dockerBuildCmd + dockerBuildDockerfile)
+			Expect(err).ToNot(HaveOccurred())
+		})
+
+		AfterAll(func(ctx context.Context) {
+			if outputDir != "" {
+				runner.Run(fmt.Sprintf("rm -rf %s", outputDir))
+			}
+		})
+
+		It("should not fail when using CDI", func(ctx context.Context) {
+			output, _, err := runner.Run("docker run --rm --runtime=nvidia --gpus=all firmware-test")
+			Expect(err).ToNot(HaveOccurred())
+			Expect(output).To(BeEmpty())
+
+			output, _, _ = runner.Run(fmt.Sprintf("ls -A %s", outputDir))
+			Expect(output).To(BeEmpty())
+		})
+
+		It("should fail when using the nvidia-container-runtime-hook", Label("legacy"), func(ctx context.Context) {
+			_, stderr, err := runner.Run("docker run --rm --runtime=runc --gpus=all firmware-test")
+			Expect(err).To(HaveOccurred())
+			Expect(stderr).To(ContainSubstring("nvidia-container-cli.real: mount error: path error:"))
+
+			output, _, _ := runner.Run(fmt.Sprintf("ls -A %s", outputDir))
+			Expect(output).To(BeEmpty())
+		})
+	})
 })

tests/e2e/runner.go

@@ -124,7 +124,7 @@ func (r remoteRunner) Run(script string) (string, string, error) {
 	// Run the script
 	err = session.Run(script)
 	if err != nil {
-		return "", "", fmt.Errorf("script execution failed: %v\nSTDOUT: %s\nSTDERR: %s", err, stdout.String(), stderr.String())
+		return "", stderr.String(), fmt.Errorf("script execution failed: %v\nSTDOUT: %s\nSTDERR: %s", err, stdout.String(), stderr.String())
 	}
 
 	// Return stdout as string if no errors