Merge pull request #755 from elezar/fix-libcuda-so

Fix bug where libcuda.so is not found in ldcache

cmd/nvidia-ctk/system/print-ldcache/print-ldcache.go

@@ -1,102 +0,0 @@
-/**
-# Copyright (c) NVIDIA CORPORATION.  All rights reserved.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-**/
-
-package createdevicenodes
-
-import (
-	"fmt"
-
-	"github.com/urfave/cli/v2"
-
-	"github.com/NVIDIA/nvidia-container-toolkit/internal/ldcache"
-	"github.com/NVIDIA/nvidia-container-toolkit/internal/logger"
-)
-
-type command struct {
-	logger logger.Interface
-}
-
-type options struct {
-	driverRoot string
-}
-
-// NewCommand constructs a command sub-command with the specified logger
-func NewCommand(logger logger.Interface) *cli.Command {
-	c := command{
-		logger: logger,
-	}
-	return c.build()
-}
-
-// build
-func (m command) build() *cli.Command {
-	opts := options{}
-
-	c := cli.Command{
-		Name:  "print-ldcache",
-		Usage: "A utility to print the contents of the ldcache",
-		Before: func(c *cli.Context) error {
-			return m.validateFlags(c, &opts)
-		},
-		Action: func(c *cli.Context) error {
-			return m.run(c, &opts)
-		},
-	}
-
-	c.Flags = []cli.Flag{
-		&cli.StringFlag{
-			Name:        "driver-root",
-			Usage:       "the path to the driver root. Device nodes will be created at `DRIVER_ROOT`/dev",
-			Value:       "/",
-			Destination: &opts.driverRoot,
-			EnvVars:     []string{"NVIDIA_DRIVER_ROOT", "DRIVER_ROOT"},
-		},
-	}
-
-	return &c
-}
-
-func (m command) validateFlags(r *cli.Context, opts *options) error {
-	return nil
-}
-
-func (m command) run(c *cli.Context, opts *options) error {
-	cache, err := ldcache.New(m.logger, opts.driverRoot)
-	if err != nil {
-		return fmt.Errorf("failed to create ldcache: %v", err)
-	}
-
-	lib32, lib64 := cache.List()
-
-	if len(lib32) == 0 {
-		m.logger.Info("No 32-bit libraries found")
-	} else {
-		m.logger.Infof("%d 32-bit libraries found", len(lib32))
-		for _, lib := range lib32 {
-			m.logger.Infof("%v", lib)
-		}
-	}
-	if len(lib64) == 0 {
-		m.logger.Info("No 64-bit libraries found")
-	} else {
-		m.logger.Infof("%d 64-bit libraries found", len(lib64))
-		for _, lib := range lib64 {
-			m.logger.Infof("%v", lib)
-		}
-	}
-
-	return nil
-}

cmd/nvidia-ctk/system/system.go

@@ -21,7 +21,6 @@ import (
 
 	devchar "github.com/NVIDIA/nvidia-container-toolkit/cmd/nvidia-ctk/system/create-dev-char-symlinks"
 	devicenodes "github.com/NVIDIA/nvidia-container-toolkit/cmd/nvidia-ctk/system/create-device-nodes"
-	ldcache "github.com/NVIDIA/nvidia-container-toolkit/cmd/nvidia-ctk/system/print-ldcache"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/logger"
 )
 
@@ -47,7 +46,6 @@ func (m command) build() *cli.Command {
 	system.Subcommands = []*cli.Command{
 		devchar.NewCommand(m.logger),
 		devicenodes.NewCommand(m.logger),
-		ldcache.NewCommand(m.logger),
 	}
 
 	return &system

internal/ldcache/ldcache.go

@@ -22,15 +22,12 @@ import (
 	"bytes"
 	"encoding/binary"
 	"errors"
-	"fmt"
 	"os"
 	"path/filepath"
-	"strings"
 	"syscall"
 	"unsafe"
 
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/logger"
-	"github.com/NVIDIA/nvidia-container-toolkit/internal/lookup/symlinks"
 )
 
 const ldcachePath = "/etc/ld.so.cache"
@@ -82,10 +79,9 @@ type entry2 struct {
 
 // LDCache represents the interface for performing lookups into the LDCache
 //
-//go:generate moq -out ldcache_mock.go . LDCache
+//go:generate moq -rm -out ldcache_mock.go . LDCache
 type LDCache interface {
 	List() ([]string, []string)
-	Lookup(...string) ([]string, []string)
 }
 
 type ldcache struct {
@@ -105,14 +101,7 @@ func New(logger logger.Interface, root string) (LDCache, error) {
 
 	logger.Debugf("Opening ld.conf at %v", path)
 	f, err := os.Open(path)
-	if os.IsNotExist(err) {
-		logger.Warningf("Could not find ld.so.cache at %v; creating empty cache", path)
-		e := &empty{
-			logger: logger,
-			path:   path,
-		}
-		return e, nil
-	} else if err != nil {
+	if err != nil {
 		return nil, err
 	}
 	defer f.Close()
@@ -196,7 +185,7 @@ type entry struct {
 }
 
 // getEntries returns the entires of the ldcache in a go-friendly struct.
-func (c *ldcache) getEntries(selected func(string) bool) []entry {
+func (c *ldcache) getEntries() []entry {
 	var entries []entry
 	for _, e := range c.entries {
 		bits := 0
@@ -223,9 +212,6 @@ func (c *ldcache) getEntries(selected func(string) bool) []entry {
 			c.logger.Debugf("Skipping invalid lib")
 			continue
 		}
-		if !selected(lib) {
-			continue
-		}
 		value := bytesToString(c.libs[e.Value:])
 		if value == "" {
 			c.logger.Debugf("Skipping invalid value for lib %v", lib)
@@ -236,51 +222,19 @@ func (c *ldcache) getEntries(selected func(string) bool) []entry {
 			bits:    bits,
 			value:   value,
 		}
-
 		entries = append(entries, e)
 	}
-
 	return entries
 }
 
 // List creates a list of libraries in the ldcache.
 // The 32-bit and 64-bit libraries are returned separately.
 func (c *ldcache) List() ([]string, []string) {
-	all := func(s string) bool { return true }
-
-	return c.resolveSelected(all)
-}
-
-// Lookup searches the ldcache for the specified prefixes.
-// The 32-bit and 64-bit libraries matching the prefixes are returned.
-func (c *ldcache) Lookup(libPrefixes ...string) ([]string, []string) {
-	c.logger.Debugf("Looking up %v in cache", libPrefixes)
-
-	// We define a functor to check whether a given library name matches any of the prefixes
-	matchesAnyPrefix := func(s string) bool {
-		for _, p := range libPrefixes {
-			if strings.HasPrefix(s, p) {
-				return true
-			}
-		}
-		return false
-	}
-
-	return c.resolveSelected(matchesAnyPrefix)
-}
-
-// resolveSelected process the entries in the LDCach based on the supplied filter and returns the resolved paths.
-// The paths are separated by bittage.
-func (c *ldcache) resolveSelected(selected func(string) bool) ([]string, []string) {
 	paths := make(map[int][]string)
 	processed := make(map[string]bool)
 
-	for _, e := range c.getEntries(selected) {
-		path, err := c.resolve(e.value)
-		if err != nil {
-			c.logger.Debugf("Could not resolve entry: %v", err)
-			continue
-		}
+	for _, e := range c.getEntries() {
+		path := filepath.Join(c.root, e.value)
 		if processed[path] {
 			continue
 		}
@@ -291,29 +245,6 @@ func (c *ldcache) resolveSelected(selected func(string) bool) ([]string, []strin
 	return paths[32], paths[64]
 }
 
-// resolve resolves the specified ldcache entry based on the value being processed.
-// The input is the name of the entry in the cache.
-func (c *ldcache) resolve(target string) (string, error) {
-	name := filepath.Join(c.root, target)
-
-	c.logger.Debugf("checking %v", name)
-
-	link, err := symlinks.Resolve(name)
-	if err != nil {
-		return "", fmt.Errorf("failed to resolve symlink: %v", err)
-	}
-	if link == name {
-		return name, nil
-	}
-
-	// We return absolute paths for all targets
-	if !filepath.IsAbs(link) || strings.HasPrefix(link, ".") {
-		link = filepath.Join(filepath.Dir(target), link)
-	}
-
-	return c.resolve(link)
-}
-
 // bytesToString converts a byte slice to a string.
 // This assumes that the byte slice is null-terminated
 func bytesToString(value []byte) string {

internal/ldcache/ldcache_mock.go

@@ -20,9 +20,6 @@ var _ LDCache = &LDCacheMock{}
 //			ListFunc: func() ([]string, []string) {
 //				panic("mock out the List method")
 //			},
-//			LookupFunc: func(strings ...string) ([]string, []string) {
-//				panic("mock out the Lookup method")
-//			},
 //		}
 //
 //		// use mockedLDCache in code that requires LDCache
@@ -33,22 +30,13 @@ type LDCacheMock struct {
 	// ListFunc mocks the List method.
 	ListFunc func() ([]string, []string)
 
-	// LookupFunc mocks the Lookup method.
-	LookupFunc func(strings ...string) ([]string, []string)
-
 	// calls tracks calls to the methods.
 	calls struct {
 		// List holds details about calls to the List method.
 		List []struct {
 		}
-		// Lookup holds details about calls to the Lookup method.
-		Lookup []struct {
-			// Strings is the strings argument value.
-			Strings []string
-		}
 	}
 	lockList sync.RWMutex
-	lockLookup sync.RWMutex
 }
 
 // List calls ListFunc.
@@ -77,35 +65,3 @@ func (mock *LDCacheMock) ListCalls() []struct {
 	mock.lockList.RUnlock()
 	return calls
 }
-
-// Lookup calls LookupFunc.
-func (mock *LDCacheMock) Lookup(strings ...string) ([]string, []string) {
-	if mock.LookupFunc == nil {
-		panic("LDCacheMock.LookupFunc: method is nil but LDCache.Lookup was just called")
-	}
-	callInfo := struct {
-		Strings []string
-	}{
-		Strings: strings,
-	}
-	mock.lockLookup.Lock()
-	mock.calls.Lookup = append(mock.calls.Lookup, callInfo)
-	mock.lockLookup.Unlock()
-	return mock.LookupFunc(strings...)
-}
-
-// LookupCalls gets all the calls that were made to Lookup.
-// Check the length with:
-//
-//	len(mockedLDCache.LookupCalls())
-func (mock *LDCacheMock) LookupCalls() []struct {
-	Strings []string
-} {
-	var calls []struct {
-		Strings []string
-	}
-	mock.lockLookup.RLock()
-	calls = mock.calls.Lookup
-	mock.lockLookup.RUnlock()
-	return calls
-}

internal/lookup/ldcache.go

@@ -0,0 +1,118 @@
+/**
+# Copyright 2024 NVIDIA CORPORATION
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+**/
+
+package lookup
+
+import (
+	"fmt"
+	"path/filepath"
+	"slices"
+
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/ldcache"
+)
+
+type ldcacheLocator struct {
+	*builder
+	resolvesTo map[string]string
+}
+
+var _ Locator = (*ldcacheLocator)(nil)
+
+func NewLdcacheLocator(opts ...Option) Locator {
+	b := newBuilder(opts...)
+
+	cache, err := ldcache.New(b.logger, b.root)
+	if err != nil {
+		b.logger.Warningf("Failed to load ldcache: %v", err)
+		if b.isOptional {
+			return &null{}
+		}
+		return &notFound{}
+	}
+
+	chain := NewSymlinkChainLocator(WithOptional(true))
+
+	resolvesTo := make(map[string]string)
+	_, libs64 := cache.List()
+	for _, library := range libs64 {
+		if _, processed := resolvesTo[library]; processed {
+			continue
+		}
+		candidates, err := chain.Locate(library)
+		if err != nil {
+			b.logger.Errorf("error processing library %s from ldcache: %v", library, err)
+			continue
+		}
+
+		if len(candidates) == 0 {
+			resolvesTo[library] = library
+			continue
+		}
+
+		// candidates represents a symlink chain.
+		// The first element represents the start of the chain and the last
+		// element the final target.
+		target := candidates[len(candidates)-1]
+		for _, candidate := range candidates {
+			resolvesTo[candidate] = target
+		}
+	}
+
+	return &ldcacheLocator{
+		builder:    b,
+		resolvesTo: resolvesTo,
+	}
+}
+
+// Locate finds the specified libraryname.
+// If the input is a library name, the ldcache is searched otherwise the
+// provided path is resolved as a symlink.
+func (l ldcacheLocator) Locate(libname string) ([]string, error) {
+	var matcher func(string, string) bool
+
+	if filepath.IsAbs(libname) {
+		matcher = func(p string, c string) bool {
+			m, _ := filepath.Match(filepath.Join(l.root, p), c)
+			return m
+		}
+	} else {
+		matcher = func(p string, c string) bool {
+			m, _ := filepath.Match(p, filepath.Base(c))
+			return m
+		}
+	}
+
+	var matches []string
+	seen := make(map[string]bool)
+	for name, target := range l.resolvesTo {
+		if !matcher(libname, name) {
+			continue
+		}
+		if seen[target] {
+			continue
+		}
+		seen[target] = true
+		matches = append(matches, target)
+	}
+
+	slices.Sort(matches)
+
+	if len(matches) == 0 && !l.isOptional {
+		return nil, fmt.Errorf("%s: %w", libname, ErrNotFound)
+	}
+
+	return matches, nil
+}

internal/lookup/ldcache_test.go

@@ -0,0 +1,77 @@
+package lookup
+
+import (
+	"path/filepath"
+	"testing"
+
+	testlog "github.com/sirupsen/logrus/hooks/test"
+	"github.com/stretchr/testify/require"
+
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/test"
+)
+
+func TestLDCacheLookup(t *testing.T) {
+	logger, _ := testlog.NewNullLogger()
+
+	moduleRoot, err := test.GetModuleRoot()
+	require.NoError(t, err)
+
+	testCases := []struct {
+		rootFs        string
+		inputs        []string
+		expected      string
+		expectedError error
+	}{
+		{
+			rootFs:        "rootfs-empty",
+			inputs:        []string{"libcuda.so.1", "libcuda.so.*", "libcuda.so.*.*", "libcuda.so.999.88.77"},
+			expectedError: ErrNotFound,
+		},
+		{
+			rootFs: "rootfs-1",
+			inputs: []string{
+				"libcuda.so.1",
+				"libcuda.so.*",
+				"libcuda.so.*.*",
+				"libcuda.so.999.88.77",
+				"/lib/x86_64-linux-gnu/libcuda.so.1",
+				"/lib/x86_64-linux-gnu/libcuda.so.*",
+				"/lib/x86_64-linux-gnu/libcuda.so.*.*",
+				"/lib/x86_64-linux-gnu/libcuda.so.999.88.77",
+			},
+			expected: "/lib/x86_64-linux-gnu/libcuda.so.999.88.77",
+		},
+		{
+			rootFs: "rootfs-2",
+			inputs: []string{
+				"libcuda.so.1",
+				"libcuda.so.*",
+				"libcuda.so.*.*",
+				"libcuda.so.999.88.77",
+				"/var/lib/nvidia/lib64/libcuda.so.1",
+				"/var/lib/nvidia/lib64/libcuda.so.*",
+				"/var/lib/nvidia/lib64/libcuda.so.*.*",
+				"/var/lib/nvidia/lib64/libcuda.so.999.88.77",
+			},
+			expected: "/var/lib/nvidia/lib64/libcuda.so.999.88.77",
+		},
+	}
+
+	for _, tc := range testCases {
+		for _, input := range tc.inputs {
+			t.Run(tc.rootFs+" "+input, func(t *testing.T) {
+				rootfs := filepath.Join(moduleRoot, "testdata", "lookup", tc.rootFs)
+				l := NewLdcacheLocator(
+					WithLogger(logger),
+					WithRoot(rootfs),
+				)
+
+				candidates, err := l.Locate(input)
+				require.ErrorIs(t, err, tc.expectedError)
+				if tc.expectedError == nil {
+					require.Equal(t, []string{filepath.Join(rootfs, tc.expected)}, candidates)
+				}
+			})
+		}
+	}
+}

internal/lookup/library.go

@@ -16,20 +16,6 @@
 
 package lookup
 
-import (
-	"fmt"
-
-	"github.com/NVIDIA/nvidia-container-toolkit/internal/ldcache"
-	"github.com/NVIDIA/nvidia-container-toolkit/internal/logger"
-)
-
-type ldcacheLocator struct {
-	logger logger.Interface
-	cache  ldcache.LDCache
-}
-
-var _ Locator = (*ldcacheLocator)(nil)
-
 // NewLibraryLocator creates a library locator using the specified options.
 func NewLibraryLocator(opts ...Option) Locator {
 	b := newBuilder(opts...)
@@ -63,39 +49,7 @@ func NewLibraryLocator(opts ...Option) Locator {
 
 	l := First(
 		symlinkLocator,
-		newLdcacheLocator(opts...),
+		NewLdcacheLocator(opts...),
 	)
 	return l
 }
-
-func newLdcacheLocator(opts ...Option) Locator {
-	b := newBuilder(opts...)
-
-	cache, err := ldcache.New(b.logger, b.root)
-	if err != nil {
-		// If we failed to open the LDCache, we default to a symlink locator.
-		b.logger.Warningf("Failed to load ldcache: %v", err)
-		return nil
-	}
-
-	return &ldcacheLocator{
-		logger: b.logger,
-		cache:  cache,
-	}
-}
-
-// Locate finds the specified libraryname.
-// If the input is a library name, the ldcache is searched otherwise the
-// provided path is resolved as a symlink.
-func (l ldcacheLocator) Locate(libname string) ([]string, error) {
-	paths32, paths64 := l.cache.Lookup(libname)
-	if len(paths32) > 0 {
-		l.logger.Warningf("Ignoring 32-bit libraries for %v: %v", libname, paths32)
-	}
-
-	if len(paths64) == 0 {
-		return nil, fmt.Errorf("64-bit library %v: %w", libname, ErrNotFound)
-	}
-
-	return paths64, nil
-}

internal/lookup/library_test.go

@@ -24,82 +24,8 @@ import (
 
 	testlog "github.com/sirupsen/logrus/hooks/test"
 	"github.com/stretchr/testify/require"
-
-	"github.com/NVIDIA/nvidia-container-toolkit/internal/ldcache"
 )
 
-func TestLDCacheLocator(t *testing.T) {
-	logger, _ := testlog.NewNullLogger()
-
-	testDir := t.TempDir()
-	symlinkDir := filepath.Join(testDir, "/lib/symlink")
-	require.NoError(t, os.MkdirAll(symlinkDir, 0755))
-
-	versionLib := filepath.Join(symlinkDir, "libcuda.so.1.2.3")
-	soLink := filepath.Join(symlinkDir, "libcuda.so")
-	sonameLink := filepath.Join(symlinkDir, "libcuda.so.1")
-
-	_, err := os.Create(versionLib)
-	require.NoError(t, err)
-	require.NoError(t, os.Symlink(versionLib, sonameLink))
-	require.NoError(t, os.Symlink(sonameLink, soLink))
-
-	lut := newLdcacheLocator(
-		WithLogger(logger),
-		WithRoot(testDir),
-	)
-
-	testCases := []struct {
-		description   string
-		libname       string
-		ldcacheMap    map[string]string
-		expected      []string
-		expectedError error
-	}{
-		{
-			description: "lib only resolves in LDCache",
-			libname:     "libcuda.so",
-			ldcacheMap: map[string]string{
-				"libcuda.so": "/lib/from/ldcache/libcuda.so.4.5.6",
-			},
-			expected: []string{"/lib/from/ldcache/libcuda.so.4.5.6"},
-		},
-		{
-			description:   "lib only not in LDCache returns error",
-			libname:       "libnotcuda.so",
-			expectedError: ErrNotFound,
-		},
-	}
-
-	for _, tc := range testCases {
-		t.Run(tc.description, func(t *testing.T) {
-			// We override the LDCache with a mock implementation
-			l := lut.(*ldcacheLocator)
-			l.cache = &ldcache.LDCacheMock{
-				LookupFunc: func(strings ...string) ([]string, []string) {
-					var result []string
-					for _, s := range strings {
-						if v, ok := tc.ldcacheMap[s]; ok {
-							result = append(result, v)
-						}
-					}
-					return nil, result
-				},
-			}
-
-			candidates, err := lut.Locate(tc.libname)
-			require.ErrorIs(t, err, tc.expectedError)
-
-			var cleanedCandidates []string
-			for _, c := range candidates {
-				// On MacOS /var and /tmp symlink to /private/var and /private/tmp which is included in the resolved path.
-				cleanedCandidates = append(cleanedCandidates, strings.TrimPrefix(c, "/private"))
-			}
-			require.EqualValues(t, tc.expected, cleanedCandidates)
-		})
-	}
-}
-
 func TestLibraryLocator(t *testing.T) {
 	logger, _ := testlog.NewNullLogger()
 

internal/lookup/null.go

@@ -1,5 +1,5 @@
 /**
-# Copyright (c) NVIDIA CORPORATION.  All rights reserved.
+# Copyright 2024 NVIDIA CORPORATION
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -14,24 +14,23 @@
 # limitations under the License.
 **/
 
-package ldcache
+package lookup
 
-import "github.com/NVIDIA/nvidia-container-toolkit/internal/logger"
+import "fmt"
 
-type empty struct {
-	logger logger.Interface
-	path   string
+// A null locator always returns an empty response.
+type null struct {
 }
 
-var _ LDCache = (*empty)(nil)
-
-// List always returns nil for an empty ldcache
-func (e *empty) List() ([]string, []string) {
+// Locate always returns empty for a null locator.
+func (l *null) Locate(string) ([]string, error) {
 	return nil, nil
 }
 
-// Lookup logs a debug message and returns nil for an empty ldcache
-func (e *empty) Lookup(prefixes ...string) ([]string, []string) {
-	e.logger.Debugf("Calling Lookup(%v) on empty ldcache: %v", prefixes, e.path)
-	return nil, nil
+// A notFound locator always returns an ErrNotFound error.
+type notFound struct {
+}
+
+func (l *notFound) Locate(s string) ([]string, error) {
+	return nil, fmt.Errorf("%s: %w", s, ErrNotFound)
 }

internal/lookup/root/root_test.go

@@ -0,0 +1,81 @@
+/**
+# Copyright 2023 NVIDIA CORPORATION
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+**/
+
+package root
+
+import (
+	"path/filepath"
+	"testing"
+
+	testlog "github.com/sirupsen/logrus/hooks/test"
+	"github.com/stretchr/testify/require"
+
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/lookup"
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/test"
+)
+
+func TestDriverLibrariesLocate(t *testing.T) {
+	logger, _ := testlog.NewNullLogger()
+
+	moduleRoot, err := test.GetModuleRoot()
+	require.NoError(t, err)
+
+	testCases := []struct {
+		rootFs        string
+		inputs        []string
+		expected      string
+		expectedError error
+	}{
+		{
+			rootFs:        "rootfs-empty",
+			inputs:        []string{"libcuda.so.1", "libcuda.so.*", "libcuda.so.*.*", "libcuda.so.999.88.77"},
+			expectedError: lookup.ErrNotFound,
+		},
+		{
+			rootFs:   "rootfs-no-cache-lib64",
+			inputs:   []string{"libcuda.so.1", "libcuda.so.*", "libcuda.so.*.*", "libcuda.so.999.88.77"},
+			expected: "/usr/lib64/libcuda.so.999.88.77",
+		},
+		{
+			rootFs:   "rootfs-1",
+			inputs:   []string{"libcuda.so.1", "libcuda.so.*", "libcuda.so.*.*", "libcuda.so.999.88.77"},
+			expected: "/lib/x86_64-linux-gnu/libcuda.so.999.88.77",
+		},
+		{
+			rootFs:   "rootfs-2",
+			inputs:   []string{"libcuda.so.1", "libcuda.so.*", "libcuda.so.*.*", "libcuda.so.999.88.77"},
+			expected: "/var/lib/nvidia/lib64/libcuda.so.999.88.77",
+		},
+	}
+
+	for _, tc := range testCases {
+		for _, input := range tc.inputs {
+			t.Run(tc.rootFs+input, func(t *testing.T) {
+				rootfs := filepath.Join(moduleRoot, "testdata", "lookup", tc.rootFs)
+				driver := New(
+					WithLogger(logger),
+					WithDriverRoot(rootfs),
+				)
+
+				candidates, err := driver.Libraries().Locate(input)
+				require.ErrorIs(t, err, tc.expectedError)
+				if tc.expectedError == nil {
+					require.Equal(t, []string{filepath.Join(rootfs, tc.expected)}, candidates)
+				}
+			})
+		}
+	}
+}

internal/lookup/symlinks.go

@@ -62,6 +62,7 @@ func (p symlinkChain) Locate(pattern string) ([]string, error) {
 		return candidates, nil
 	}
 
+	var filenames []string
 	found := make(map[string]bool)
 	for len(candidates) > 0 {
 		candidate := candidates[0]
@@ -70,6 +71,7 @@ func (p symlinkChain) Locate(pattern string) ([]string, error) {
 			continue
 		}
 		found[candidate] = true
+		filenames = append(filenames, candidate)
 
 		target, err := symlinks.Resolve(candidate)
 		if err != nil {
@@ -88,11 +90,6 @@ func (p symlinkChain) Locate(pattern string) ([]string, error) {
 			candidates = append(candidates, target)
 		}
 	}
-
-	var filenames []string
-	for f := range found {
-		filenames = append(filenames, f)
-	}
 	return filenames, nil
 }
 

testdata/lookup/rootfs-1/README.md

@@ -0,0 +1,2 @@
+This rootfs represents a host with the CUDA driver libraries installed in
+/lib/x86_64-linux-gnu. The included /etc/ld.so.cache was copied from such as system.

testdata/lookup/rootfs-1/lib/x86_64-linux-gnu/libcuda.so.1

@@ -0,0 +1 @@
+libcuda.so.999.88.77

testdata/lookup/rootfs-2/README.md

@@ -0,0 +1,3 @@
+This rootfs represents a host with the CUDA driver libraries installed in
+/var/lib/nvidia/lib64. The included /etc/ld.so.cache was generated in a container
+simulating such as system.

testdata/lookup/rootfs-2/var/lib/nvidia/lib64/libcuda.so.1

@@ -0,0 +1 @@
+libcuda.so.999.88.77

testdata/lookup/rootfs-empty/README.md

@@ -0,0 +1 @@
+The folders represents an empty rootfs.

testdata/lookup/rootfs-no-cache-lib64/usr/lib64/libcuda.so.1

@@ -0,0 +1 @@
+libcuda.so.999.88.77