[CWS] Add namespace ID field resolver for ptrace

pkg/security/probe/field_handlers_ebpf.go

@@ -20,6 +20,7 @@ import (
 	"github.com/DataDog/datadog-agent/pkg/security/resolvers"
 	sprocess "github.com/DataDog/datadog-agent/pkg/security/resolvers/process"
 	"github.com/DataDog/datadog-agent/pkg/security/secl/containerutils"
+	"github.com/DataDog/datadog-agent/pkg/security/utils"
 
 	"github.com/DataDog/datadog-agent/pkg/security/secl/args"
 	"github.com/DataDog/datadog-agent/pkg/security/secl/model"
@@ -230,7 +231,7 @@ func (fh *EBPFFieldHandlers) ResolveRights(_ *model.Event, e *model.FileFields)
 	return int(e.Mode) & (syscall.S_ISUID | syscall.S_ISGID | syscall.S_ISVTX | syscall.S_IRWXU | syscall.S_IRWXG | syscall.S_IRWXO)
 }
 
-// ResolveChownUID resolves the ResolveProcessCacheEntry id of a chown event to a username
+// ResolveChownUID resolves the user id of a chown event to a username
 func (fh *EBPFFieldHandlers) ResolveChownUID(ev *model.Event, e *model.ChownEvent) string {
 	if len(e.User) == 0 {
 		e.User, _ = fh.resolvers.UserGroupResolver.ResolveUser(int(e.UID), ev.ContainerContext.ContainerID)
@@ -731,3 +732,17 @@ func (fh *EBPFFieldHandlers) ResolveOnDemandArg4Str(_ *model.Event, e *model.OnD
 func (fh *EBPFFieldHandlers) ResolveOnDemandArg4Uint(_ *model.Event, e *model.OnDemandEvent) int {
 	return int(binary.NativeEndian.Uint64(e.Data[192 : 192+8]))
 }
+
+// ResolveProcessNSID resolves the process namespace ID
+func (fh *EBPFFieldHandlers) ResolveProcessNSID(e *model.Event) (uint64, error) {
+	if e.ProcessCacheEntry.Process.NSID != 0 {
+		return e.ProcessCacheEntry.Process.NSID, nil
+	}
+
+	nsid, err := utils.GetProcessPidNamespace(e.ProcessCacheEntry.Process.Pid)
+	if err != nil {
+		return 0, err
+	}
+	e.ProcessCacheEntry.Process.NSID = nsid
+	return nsid, nil
+}

pkg/security/probe/probe_ebpf.go

@@ -1090,7 +1090,14 @@ func (p *EBPFProbe) handleEvent(CPU int, data []byte) {
 				if containerID == "" && event.PTrace.Request != unix.PTRACE_ATTACH {
 					pidToResolve = event.PTrace.NSPID
 				} else {
-					pid, err := utils.TryToResolveTraceePid(event.ProcessContext.Process.Pid, event.PTrace.NSPID)
+					nsid, err := p.fieldHandlers.ResolveProcessNSID(event)
+					if err != nil {
+						seclog.Debugf("PTrace NSID resolution error for process %s in container %s: %v",
+							event.ProcessContext.Process.FileEvent.PathnameStr, containerID, err)
+						return
+					}
+
+					pid, err := utils.TryToResolveTraceePid(event.ProcessContext.Process.Pid, nsid, event.PTrace.NSPID)
 					if err != nil {
 						seclog.Debugf("PTrace tracee resolution error for process %s in container %s: %v",
 							event.ProcessContext.Process.FileEvent.PathnameStr, containerID, err)

pkg/security/utils/proc_linux.go

@@ -567,22 +567,14 @@ var isNsPidAvailable = sync.OnceValue(func() bool {
 })
 
 // TryToResolveTraceePid tries to resolve and returnt the HOST tracee PID, given the HOST tracer PID and the namespaced tracee PID.
-func TryToResolveTraceePid(hostTracerPID, NsTraceePid uint32) (uint32, error) {
+func TryToResolveTraceePid(hostTracerPID uint32, tracerNSID uint64, NsTraceePid uint32) (uint32, error) {
 	// Look if the NSpid status field is available or not (it should be, except for Centos7).
 	if isNsPidAvailable() {
 		/*
 		   If it's available, we will search for an host pid having the same PID namespace as the
 		   tracer, and having the corresponding NS PID in its status field
 		*/
-
-		// 1. get the pid namespace of the tracer
-		ns, err := GetProcessPidNamespace(hostTracerPID)
-		if err != nil {
-			return 0, fmt.Errorf("Failed to resolve PID namespace: %v", err)
-		}
-
-		// 2. find the host pid matching the arg pid with he tracer namespace
-		pid, err := FindPidNamespace(NsTraceePid, ns)
+		pid, err := FindPidNamespace(NsTraceePid, tracerNSID)
 		if err != nil {
 			return 0, fmt.Errorf("Failed to resolve tracee PID namespace: %v", err)
 		}