update:fix update pids-limit=0 error

Signed-off-by: ningmingxiao <ning.mingxiao@zte.com.cn>

Author: ningmingxiao

cmd/nerdctl/container/container_run_cgroup_linux_test.go

@@ -18,6 +18,7 @@ package container
 
 import (
 	"bytes"
+	"context"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -27,11 +28,14 @@ import (
 	"gotest.tools/v3/assert"
 
 	"github.com/containerd/cgroups/v3"
+	containerd "github.com/containerd/containerd/v2/client"
 	"github.com/containerd/continuity/testutil/loopback"
 
 	"github.com/containerd/nerdctl/v2/pkg/cmd/container"
+	"github.com/containerd/nerdctl/v2/pkg/idutil/containerwalker"
 	"github.com/containerd/nerdctl/v2/pkg/testutil"
 	"github.com/containerd/nerdctl/v2/pkg/testutil/nerdtest"
+	"github.com/containerd/nerdctl/v2/pkg/testutil/test"
 )
 
 func TestRunCgroupV2(t *testing.T) {
@@ -170,6 +174,53 @@ func TestRunCgroupV1(t *testing.T) {
 	base.Cmd("run", "--rm", "--cpu-quota", "42000", "--cpu-period", "100000", "--cpuset-mems", "0", "--memory", "42m", "--memory-reservation", "6m", "--memory-swap", "100m", "--memory-swappiness", "0", "--pids-limit", "42", "--cpu-shares", "2000", "--cpuset-cpus", "0-1", testutil.AlpineImage, "cat", quota, period, cpusetMems, memoryLimit, memoryReservation, memorySwap, memorySwappiness, pidsLimit, cpuShare, cpusetCpus).AssertOutExactly(expected)
 }
 
+// TestIssue3781 tests https://github.com/containerd/nerdctl/issues/3781
+func TestIssue3781(t *testing.T) {
+	t.Parallel()
+	testCase := nerdtest.Setup()
+	testCase.Require = test.Not(nerdtest.Docker)
+
+	base := testutil.NewBase(t)
+	info := base.Info()
+	switch info.CgroupDriver {
+	case "none", "":
+		t.Skip("test requires cgroup driver")
+	}
+	containerName := testutil.Identifier(t)
+	base.Cmd("run", "-d", "--name", containerName, testutil.AlpineImage, "sleep", "infinity").AssertOK()
+	defer func() {
+		base.Cmd("rm", "-f", containerName)
+	}()
+	base.Cmd("update", "--cpuset-cpus", "0-1", containerName).AssertOK()
+	addr := base.ContainerdAddress()
+	client, err := containerd.New(addr, containerd.WithDefaultNamespace(testutil.Namespace))
+	assert.NilError(base.T, err)
+	ctx := context.Background()
+
+	// get container id by container name.
+	var cid string
+	var args []string
+	args = append(args, containerName)
+	walker := &containerwalker.ContainerWalker{
+		Client: client,
+		OnFound: func(ctx context.Context, found containerwalker.Found) error {
+			if found.MatchCount > 1 {
+				return fmt.Errorf("multiple IDs found with provided prefix: %s", found.Req)
+			}
+			cid = found.Container.ID()
+			return nil
+		},
+	}
+	err = walker.WalkAll(ctx, args, true)
+	assert.NilError(base.T, err)
+
+	container, err := client.LoadContainer(ctx, cid)
+	assert.NilError(base.T, err)
+	spec, err := container.Spec(ctx)
+	assert.NilError(base.T, err)
+	assert.Equal(t, spec.Linux.Resources.Pids == nil, true)
+}
+
 func TestRunDevice(t *testing.T) {
 	if os.Geteuid() != 0 || userns.RunningInUserNS() {
 		t.Skip("test requires the root in the initial user namespace")

cmd/nerdctl/container/container_update.go

@@ -266,16 +266,18 @@ func updateContainer(ctx context.Context, client *containerd.Client, id string,
 		if spec.Linux.Resources == nil {
 			spec.Linux.Resources = &runtimespec.LinuxResources{}
 		}
-		if spec.Linux.Resources.BlockIO == nil {
-			spec.Linux.Resources.BlockIO = &runtimespec.LinuxBlockIO{}
-		}
 		if cmd.Flags().Changed("blkio-weight") {
+			if spec.Linux.Resources.BlockIO == nil {
+				spec.Linux.Resources.BlockIO = &runtimespec.LinuxBlockIO{}
+			}
 			if spec.Linux.Resources.BlockIO.Weight != &opts.BlkioWeight {
 				spec.Linux.Resources.BlockIO.Weight = &opts.BlkioWeight
 			}
 		}
-		if spec.Linux.Resources.CPU == nil {
-			spec.Linux.Resources.CPU = &runtimespec.LinuxCPU{}
+		if cmd.Flags().Changed("cpu-shares") || cmd.Flags().Changed("cpu-quota") || cmd.Flags().Changed("cpu-period") || cmd.Flags().Changed("cpus") || cmd.Flags().Changed("cpuset-mems") || cmd.Flags().Changed("cpuset-cpus") {
+			if spec.Linux.Resources.CPU == nil {
+				spec.Linux.Resources.CPU = &runtimespec.LinuxCPU{}
+			}
 		}
 		if cmd.Flags().Changed("cpu-shares") {
 			if spec.Linux.Resources.CPU.Shares != &opts.CPUShares {
@@ -308,8 +310,10 @@ func updateContainer(ctx context.Context, client *containerd.Client, id string,
 				spec.Linux.Resources.CPU.Cpus = opts.CpusetCpus
 			}
 		}
-		if spec.Linux.Resources.Memory == nil {
-			spec.Linux.Resources.Memory = &runtimespec.LinuxMemory{}
+		if cmd.Flags().Changed("memory") || cmd.Flags().Changed("memory-reservation") {
+			if spec.Linux.Resources.Memory == nil {
+				spec.Linux.Resources.Memory = &runtimespec.LinuxMemory{}
+			}
 		}
 		if cmd.Flags().Changed("memory") {
 			if spec.Linux.Resources.Memory.Limit != &opts.MemoryLimitInBytes {
@@ -324,10 +328,10 @@ func updateContainer(ctx context.Context, client *containerd.Client, id string,
 				spec.Linux.Resources.Memory.Reservation = &opts.MemoryReservation
 			}
 		}
-		if spec.Linux.Resources.Pids == nil {
-			spec.Linux.Resources.Pids = &runtimespec.LinuxPids{}
-		}
 		if cmd.Flags().Changed("pids-limit") {
+			if spec.Linux.Resources.Pids == nil {
+				spec.Linux.Resources.Pids = &runtimespec.LinuxPids{}
+			}
 			if spec.Linux.Resources.Pids.Limit != opts.PidsLimit {
 				spec.Linux.Resources.Pids.Limit = opts.PidsLimit
 			}