[CWS] add ubuntu 18.04 with kernel 4.15 to CI + fix constants

.gitlab/functional_test/security_agent.yml

@@ -37,7 +37,7 @@ kitchen_test_security_agent_x64:
       - KITCHEN_PLATFORM: "centos"
         KITCHEN_OSVERS: "centos-77,rhel-85"
       - KITCHEN_PLATFORM: "ubuntu"
-        KITCHEN_OSVERS: "ubuntu-18-04,ubuntu-18-04-3"
+        KITCHEN_OSVERS: "ubuntu-18-04-0,ubuntu-18-04,ubuntu-18-04-3"
       - KITCHEN_PLATFORM: "ubuntu"
         KITCHEN_OSVERS: "ubuntu-20-04,ubuntu-20-04-2,ubuntu-21-10"
       - KITCHEN_PLATFORM: "suse"

pkg/security/ebpf/kernel/kernel.go

@@ -145,6 +145,19 @@ func (k *Version) IsDebianKernel() bool {
 	return k.OsRelease["ID"] == "debian"
 }
 
+// UbuntuKernelVersion returns a parsed ubuntu kernel version or nil if not on ubuntu or if parsing failed
+func (k *Version) UbuntuKernelVersion() *kernel.UbuntuKernelVersion {
+	if k.OsRelease["ID"] != "ubuntu" {
+		return nil
+	}
+
+	ukv, err := kernel.NewUbuntuKernelVersion(k.UnameRelease)
+	if err != nil {
+		return nil
+	}
+	return ukv
+}
+
 // IsRH7Kernel returns whether the kernel is a rh7 kernel
 func (k *Version) IsRH7Kernel() bool {
 	return (k.OsRelease["ID"] == "centos" || k.OsRelease["ID"] == "rhel") && k.OsRelease["VERSION_ID"] == "7"

pkg/security/probe/constantfetch/fallback.go

@@ -118,6 +118,17 @@ func (f *FallbackConstantFetcher) FinishAndGetResults() (map[string]uint64, erro
 func getSizeOfStructInode(kv *kernel.Version) uint64 {
 	sizeOf := uint64(600)
 
+	// see https://ubuntu.com/security/CVE-2019-10638
+	increaseSizeAbiMinVersion := map[string]int{
+		"generic":      99,
+		"generic-lpae": 99,
+		"lowlatency":   99,
+		"gke":          1058,
+		"gcp":          1093,
+		"aws":          1066,
+		"azure":        1082,
+	}
+
 	switch {
 	case kv.IsRH7Kernel():
 		sizeOf = 584
@@ -139,6 +150,12 @@ func getSizeOfStructInode(kv *kernel.Version) uint64 {
 		sizeOf = 584
 	case kv.IsAmazonLinuxKernel() && kv.IsInRangeCloseOpen(kernel.Kernel5_10, kernel.Kernel5_11):
 		sizeOf = 584
+	case kv.IsInRangeCloseOpen(kernel.Kernel4_15, kernel.Kernel4_16):
+		if ubuntuAbiVersionCheck(kv, increaseSizeAbiMinVersion) {
+			sizeOf = 608
+		} else {
+			sizeOf = 600
+		}
 	case kv.Code != 0 && kv.Code < kernel.Kernel4_16:
 		sizeOf = 608
 	case kv.IsInRangeCloseOpen(kernel.Kernel5_0, kernel.Kernel5_1):
@@ -184,7 +201,9 @@ func getSignalTTYOffset(kv *kernel.Version) uint64 {
 		ttyOffset = 368
 	case kv.IsAmazonLinuxKernel() && kv.IsInRangeCloseOpen(kernel.Kernel5_4, kernel.Kernel5_5):
 		ttyOffset = 400
-	case kv.IsInRangeCloseOpen(kernel.Kernel4_13, kernel.Kernel4_19):
+	case kv.IsInRangeCloseOpen(kernel.Kernel4_15, kernel.Kernel4_16):
+		ttyOffset = 368
+	case kv.IsInRangeCloseOpen(kernel.Kernel4_16, kernel.Kernel4_19):
 		ttyOffset = 376
 	case kv.IsInRangeCloseOpen(kernel.Kernel4_19, kernel.Kernel5_0):
 		ttyOffset = 400
@@ -279,6 +298,8 @@ func getBpfMapNameOffset(kv *kernel.Version) uint64 {
 	case kv.IsSLES12Kernel():
 		nameOffset = 176
 
+	case kv.IsInRangeCloseOpen(kernel.Kernel4_15, kernel.Kernel4_18):
+		nameOffset = 112
 	case kv.IsInRangeCloseOpen(kernel.Kernel4_18, kernel.Kernel5_1):
 		nameOffset = 176
 	case kv.IsInRangeCloseOpen(kernel.Kernel5_1, kernel.Kernel5_3):
@@ -316,6 +337,8 @@ func getBpfProgAuxOffset(kv *kernel.Version) uint64 {
 	switch {
 	case kv.IsAmazonLinuxKernel() && kv.IsInRangeCloseOpen(kernel.Kernel4_14, kernel.Kernel4_15):
 		auxOffset = 24
+	case kv.IsInRangeCloseOpen(kernel.Kernel4_15, kernel.Kernel4_16):
+		auxOffset = 24
 	case kv.Code >= kernel.Kernel5_13:
 		auxOffset = 56
 	}
@@ -328,7 +351,8 @@ func getBpfProgTagOffset(kv *kernel.Version) uint64 {
 	switch {
 	case kv.IsAmazonLinuxKernel() && kv.IsInRangeCloseOpen(kernel.Kernel4_14, kernel.Kernel4_15):
 		progTagOffset = 16
-	default:
+	case kv.IsInRangeCloseOpen(kernel.Kernel4_15, kernel.Kernel4_16):
+		progTagOffset = 16
 	}
 
 	return progTagOffset
@@ -357,7 +381,7 @@ func getBpfProgAuxIDOffset(kv *kernel.Version) uint64 {
 	case kv.IsAmazonLinuxKernel() && kv.IsInRangeCloseOpen(kernel.Kernel4_14, kernel.Kernel4_15):
 		idOffset = 16
 
-	case kv.IsInRangeCloseOpen(kernel.Kernel4_18, kernel.Kernel5_0):
+	case kv.IsInRangeCloseOpen(kernel.Kernel4_15, kernel.Kernel5_0):
 		idOffset = 16
 	case kv.IsInRangeCloseOpen(kernel.Kernel5_0, kernel.Kernel5_4):
 		idOffset = 20
@@ -387,6 +411,8 @@ func getBpfProgAuxNameOffset(kv *kernel.Version) uint64 {
 	case kv.IsCOSKernel() && kv.IsInRangeCloseOpen(kernel.Kernel5_10, kernel.Kernel5_11):
 		nameOffset = 544
 
+	case kv.IsInRangeCloseOpen(kernel.Kernel4_15, kernel.Kernel4_18):
+		nameOffset = 128
 	case kv.IsInRangeCloseOpen(kernel.Kernel4_18, kernel.Kernel4_19):
 		nameOffset = 152
 	case kv.IsInRangeCloseOpen(kernel.Kernel4_19, kernel.Kernel5_0):
@@ -435,6 +461,10 @@ func getPIDNumbersOffset(kv *kernel.Version) uint64 {
 
 	case kv.IsInRangeCloseOpen(kernel.Kernel4_15, kernel.Kernel5_0):
 		pidNumbersOffset = 48
+	case kv.IsInRangeCloseOpen(kernel.Kernel5_0, kernel.Kernel5_1):
+		pidNumbersOffset = 56
+	case kv.IsInRangeCloseOpen(kernel.Kernel5_1, kernel.Kernel5_3):
+		pidNumbersOffset = 48
 	case kv.IsInRangeCloseOpen(kernel.Kernel5_0, kernel.Kernel5_3):
 		pidNumbersOffset = 56
 	case kv.IsInRangeCloseOpen(kernel.Kernel5_3, kernel.Kernel5_7):
@@ -522,7 +552,21 @@ func getNetDeviceIfindexOffset(kv *kernel.Version) uint64 {
 }
 
 func getNetNSOffset(kv *kernel.Version) uint64 {
+	// see https://ubuntu.com/security/CVE-2019-10638
+	hashMixAbiMinVersion := map[string]int{
+		"generic":      60,
+		"generic-lpae": 60,
+		"lowlatency":   60,
+		"oracle":       1022,
+		"gke":          1041,
+		"gcp":          1042,
+		"aws":          1047,
+		"azure":        1018,
+	}
+
 	switch {
+	case kv.IsInRangeCloseOpen(kernel.Kernel4_15, kernel.Kernel4_16) && ubuntuAbiVersionCheck(kv, hashMixAbiMinVersion):
+		fallthrough
 	// Commit 355b98553789b646ed97ad801a619ff898471b92 introduces a hashmix field for security
 	// purposes. This commit was cherry-picked in stable releases 4.9.168, 4.14.111, 4.19.34 and 5.0.7
 	// and is part of master since 5.1
@@ -609,3 +653,17 @@ func getFlowi6SAddrOffset(kv *kernel.Version) uint64 {
 func getFlowi6ULIOffset(kv *kernel.Version) uint64 {
 	return getFlowi6SAddrOffset(kv) + 20
 }
+
+func ubuntuAbiVersionCheck(kv *kernel.Version, minAbiPerFlavor map[string]int) bool {
+	ukv := kv.UbuntuKernelVersion()
+	if ukv == nil {
+		return false
+	}
+
+	minAbi, present := minAbiPerFlavor[ukv.Flavor]
+	if !present {
+		return false
+	}
+
+	return ukv.Abi >= minAbi
+}

pkg/util/kernel/version.go

@@ -139,3 +139,53 @@ func parseDebianVersion(str string) (Version, error) {
 	}
 	return ParseReleaseString(match[1])
 }
+
+// UbuntuKernelVersion represents a version from an ubuntu kernel
+// Please see: https://ubuntu.com/kernel for the documentation of this scheme
+type UbuntuKernelVersion struct {
+	Major  int
+	Minor  int
+	Patch  int // always 0
+	Abi    int
+	Flavor string
+}
+
+var ubuntuKernelVersionRegex = regexp.MustCompile(`^(\d+)\.(\d+)\.(0)-(\d+)-([[:lower:]-]+)$`)
+
+// NewUbuntuKernelVersion parses the ubuntu release string and returns a structure with each extracted fields
+func NewUbuntuKernelVersion(unameRelease string) (*UbuntuKernelVersion, error) {
+	match := ubuntuKernelVersionRegex.FindStringSubmatch(unameRelease)
+	if len(match) == 0 {
+		return nil, fmt.Errorf("failed to parse ubuntu kernel version")
+	}
+
+	major, err := strconv.ParseInt(match[1], 10, 0)
+	if err != nil {
+		return nil, err
+	}
+
+	minor, err := strconv.ParseInt(match[2], 10, 0)
+	if err != nil {
+		return nil, err
+	}
+
+	patch, err := strconv.ParseInt(match[3], 10, 0)
+	if err != nil {
+		return nil, err
+	}
+
+	abi, err := strconv.ParseInt(match[4], 10, 0)
+	if err != nil {
+		return nil, err
+	}
+
+	flavor := match[5]
+
+	return &UbuntuKernelVersion{
+		Major:  int(major),
+		Minor:  int(minor),
+		Patch:  int(patch),
+		Abi:    int(abi),
+		Flavor: flavor,
+	}, nil
+}

pkg/util/kernel/version_test.go

@@ -28,3 +28,17 @@ func TestLinuxKernelVersionCode(t *testing.T) {
 	assert.Equal(t, Version(197132).String(), "3.2.12")
 	assert.Equal(t, Version(263168).String(), "4.4.0")
 }
+
+func TestUbuntuKernelVersion(t *testing.T) {
+	ubuntuVersion := "5.13.0-35-generic-lpae"
+	ukv, err := NewUbuntuKernelVersion(ubuntuVersion)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	assert.Equal(t, ukv.Major, 5)
+	assert.Equal(t, ukv.Minor, 13)
+	assert.Equal(t, ukv.Patch, 0)
+	assert.Equal(t, ukv.Abi, 35)
+	assert.Equal(t, ukv.Flavor, "generic-lpae")
+}

test/kitchen/platforms.json

@@ -57,6 +57,7 @@
             "x86_64": {
                 "ubuntu-14-04": "urn,Canonical:UbuntuServer:14.04.5-LTS:14.04.201905140",
                 "ubuntu-16-04": "urn,Canonical:UbuntuServer:16.04.0-LTS:16.04.202106110",
+                "ubuntu-18-04-0": "urn,Canonical:UbuntuServer:18.04-LTS:18.04.201809110",
                 "ubuntu-18-04": "urn,Canonical:UbuntuServer:18.04-LTS:18.04.201906040",
                 "ubuntu-18-04-3": "urn,Canonical:UbuntuServer:18.04-LTS:18.04.201912180",
                 "ubuntu-20-04": "urn,Canonical:0001-com-ubuntu-server-focal:20_04-lts:20.04.202004230",