Revert "Merge pull request #696 from elezar/check-link-resolution"

This reverts commit c490baab63, reversing
changes made to 32486cf1e9.

Signed-off-by: Evan Lezar <elezar@nvidia.com>

cmd/nvidia-cdi-hook/create-symlinks/create-symlinks.go

@@ -149,12 +149,13 @@ func (m command) run(c *cli.Context, cfg *config) error {
 	for _, l := range links {
 		parts := strings.Split(l, "::")
 		if len(parts) != 2 {
-			return fmt.Errorf("invalid symlink specification %v", l)
+			m.logger.Warningf("Invalid link specification %v", l)
+			continue
 		}
 
 		err := m.createLink(created, cfg.hostRoot, containerRoot, parts[0], parts[1])
 		if err != nil {
-			return fmt.Errorf("failed to create link %v: %w", parts, err)
+			m.logger.Warningf("Failed to create link %v: %v", parts, err)
 		}
 	}
 
@@ -165,27 +166,16 @@ func (m command) run(c *cli.Context, cfg *config) error {
 func (m command) createLink(created map[string]bool, hostRoot string, containerRoot string, target string, link string) error {
 	linkPath, err := changeRoot(hostRoot, containerRoot, link)
 	if err != nil {
-		return fmt.Errorf("failed to resolve path for link %v relative to %v: %w", link, containerRoot, err)
+		m.logger.Warningf("Failed to resolve path for link %v relative to %v: %v", link, containerRoot, err)
 	}
 	if created[linkPath] {
 		m.logger.Debugf("Link %v already created", linkPath)
 		return nil
 	}
-	if err := assertPathInRoot(containerRoot, linkPath); err != nil {
-		return err
-	}
 
 	targetPath, err := changeRoot(hostRoot, "/", target)
 	if err != nil {
-		return fmt.Errorf("failed to resolve path for target %v relative to %v: %w", target, "/", err)
+		m.logger.Warningf("Failed to resolve path for target %v relative to %v: %v", target, "/", err)
-	}
-
-	parent := containerRoot
-	if !filepath.IsAbs(targetPath) {
-		parent = filepath.Dir(linkPath)
-	}
-	if err := assertPathInRoot(containerRoot, filepath.Join(parent, targetPath)); err != nil {
-		return err
 	}
 
 	m.logger.Infof("Symlinking %v to %v", linkPath, targetPath)
@@ -201,59 +191,6 @@ func (m command) createLink(created map[string]bool, hostRoot string, containerR
 	return nil
 }
 
-// assertPathInRoot ensures that the specified path is a subpath of root.
-// This includes the resolution of relative paths and symlinks.
-func assertPathInRoot(root string, path string) error {
-	resolved, err := tryResolveLink(filepath.Clean(path))
-	if err != nil {
-		return err
-	}
-	if !strings.HasPrefix(resolved, root) {
-		return fmt.Errorf("path %v resolves to %v which is outside the root %v", path, resolved, root)
-	}
-	return nil
-}
-
-// tryResolveLink resolves the specified path following symlinks.
-// If the path does not exist, recursively resolve the parent of the path until
-// one resolves successfully.
-//
-// For example, assuming that we call this with a path
-//
-//	/container-root/foo/bar/baz.so
-//
-// If this path exists, then the symlink evaluation will succeed and the target
-// will be returned.
-//
-// Assuming that /container-root/foo exists, but /container-root/foo/bar does
-// not, the first call to EvalSymlinks with argument
-// /container-root/foo/bar/baz.so will fail resulting in a recursive call to
-// this function with an argument /container-root/foo/bar. Since this path also
-// doesn't exist this will result in an additional recursive call with an
-// argument /container-root/foo. Here EvalSymlinks will succeed and the strings
-// /bar and /baz.so will be appended to the result as we return along the
-// recursive call stack.
-//
-// If none of the parents of the path (with the exception of /) exist the path
-// will be returned as is with no error.
-func tryResolveLink(path string) (string, error) {
-	if path == "" || path == "/" {
-		return path, nil
-	}
-
-	resolved, err := filepath.EvalSymlinks(path)
-	if os.IsNotExist(err) {
-		resolvedParent, err := tryResolveLink(filepath.Dir(path))
-		if err != nil {
-			return "", err
-		}
-		resolved := filepath.Join(resolvedParent, filepath.Base(path))
-		return resolved, nil
-	}
-
-	return resolved, err
-}
-
 func changeRoot(current string, new string, path string) (string, error) {
 	if !filepath.IsAbs(path) {
 		return path, nil