@@ -110,6 +110,9 @@ func (daemon *Daemon) getInspectData(container *container.Container, size bool)

 		hostConfig.Links = append(hostConfig.Links, fmt.Sprintf("%s:%s", child.Name, linkAlias))

 	}

+	// We merge the Ulimits from hostConfig with daemon default

+	daemon.mergeUlimits(&hostConfig)

+

 	var containerHealth *types.Health

 	if container.State.Health != nil {

 		containerHealth = &types.Health{

@@ -115,19 +115,11 @@ func setDevices(s *specs.Spec, c *container.Container) error {

 func setRlimits(daemon *Daemon, s *specs.Spec, c *container.Container) error {

 	var rlimits []specs.Rlimit

-	ulimits := c.HostConfig.Ulimits

-	// Merge ulimits with daemon defaults

-	ulIdx := make(map[string]struct{})

-	for _, ul := range ulimits {

-		ulIdx[ul.Name] = struct{}{}

-	}

-	for name, ul := range daemon.configStore.Ulimits {

-		if _, exists := ulIdx[name]; !exists {

-			ulimits = append(ulimits, ul)

-		}

-	}

-

-	for _, ul := range ulimits {

+	// We want to leave the original HostConfig alone so make a copy here

+	hostConfig := *c.HostConfig

+	// Merge with the daemon defaults

+	daemon.mergeUlimits(&hostConfig)

+	for _, ul := range hostConfig.Ulimits {

 		rlimits = append(rlimits, specs.Rlimit{

 			Type: "RLIMIT_" + strings.ToUpper(ul.Name),

 			Soft: uint64(ul.Soft),

@@ -709,3 +701,19 @@ func clearReadOnly(m *specs.Mount) {

 	}

 	m.Options = opt

 }

+

+// mergeUlimits merge the Ulimits from HostConfig with daemon defaults, and update HostConfig

+func (daemon *Daemon) mergeUlimits(c *containertypes.HostConfig) {

+	ulimits := c.Ulimits

+	// Merge ulimits with daemon defaults

+	ulIdx := make(map[string]struct{})

+	for _, ul := range ulimits {

+		ulIdx[ul.Name] = struct{}{}

+	}

+	for name, ul := range daemon.configStore.Ulimits {

+		if _, exists := ulIdx[name]; !exists {

+			ulimits = append(ulimits, ul)

+		}

+	}

+	c.Ulimits = ulimits

+}

@@ -1,6 +1,7 @@

 package daemon

 import (

+	containertypes "github.com/docker/docker/api/types/container"

 	"github.com/docker/docker/container"

 	"github.com/docker/docker/libcontainerd"

 	"github.com/docker/docker/oci"

@@ -10,3 +11,9 @@ func (daemon *Daemon) createSpec(c *container.Container) (*libcontainerd.Spec, e

 	s := oci.DefaultSpec()

 	return (*libcontainerd.Spec)(&s), nil

 }

+

+// mergeUlimits merge the Ulimits from HostConfig with daemon defaults, and update HostConfig

+// It will do nothing on non-Linux platform

+func (daemon *Daemon) mergeUlimits(c *containertypes.HostConfig) {

+	return

+}

@@ -7,6 +7,7 @@ import (

 	"path/filepath"

 	"syscall"

+	containertypes "github.com/docker/docker/api/types/container"

 	"github.com/docker/docker/container"

 	"github.com/docker/docker/image"

 	"github.com/docker/docker/layer"

@@ -192,3 +193,9 @@ func escapeArgs(args []string) []string {

 	}

 	return escapedArgs

 }

+

+// mergeUlimits merge the Ulimits from HostConfig with daemon defaults, and update HostConfig

+// It will do nothing on non-Linux platform

+func (daemon *Daemon) mergeUlimits(c *containertypes.HostConfig) {

+	return

+}

@@ -4518,3 +4518,25 @@ exec "$@"`,

 	c.Assert(err, check.NotNil)

 	c.Assert(err.Error(), checker.Contains, "No command specified")

 }

+

+func (s *DockerDaemonSuite) TestRunWithUlimitAndDaemonDefault(c *check.C) {

+	c.Assert(s.d.StartWithBusybox("--debug", "--default-ulimit=nofile=65535"), checker.IsNil)

+

+	name := "test-A"

+	_, err := s.d.Cmd("run", "--name", name, "-d", "busybox", "top")

+	c.Assert(err, checker.IsNil)

+	c.Assert(s.d.waitRun(name), check.IsNil)

+

+	out, err := s.d.Cmd("inspect", "--format", "{{.HostConfig.Ulimits}}", name)

+	c.Assert(err, checker.IsNil)

+	c.Assert(out, checker.Contains, "[nofile=65535:65535]")

+

+	name = "test-B"

+	_, err = s.d.Cmd("run", "--name", name, "--ulimit=nofile=42", "-d", "busybox", "top")

+	c.Assert(err, checker.IsNil)

+	c.Assert(s.d.waitRun(name), check.IsNil)

+

+	out, err = s.d.Cmd("inspect", "--format", "{{.HostConfig.Ulimits}}", name)

+	c.Assert(err, checker.IsNil)

+	c.Assert(out, checker.Contains, "[nofile=42:42]")

+}