From 46183cf8737d2b478923e16b545dce483c9b3d03 Mon Sep 17 00:00:00 2001 From: Matthew Heon Date: Thu, 10 Dec 2020 11:43:59 -0500 Subject: Ignore containers.conf sysctls when sharing namespaces The existing code prevents containers.conf default sysctls from being added if the container uses a host namespace. This patch expands that to not just host namespaces, but also *shared* namespaces - so we never modify another container's (or a pod's) namespaces without being explicitly directed to do so by the user. Signed-off-by: Matthew Heon --- pkg/specgen/generate/security.go | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/pkg/specgen/generate/security.go b/pkg/specgen/generate/security.go index dee140282..b69bd9091 100644 --- a/pkg/specgen/generate/security.go +++ b/pkg/specgen/generate/security.go @@ -178,6 +178,10 @@ func securityConfigureGenerator(s *specgen.SpecGenerator, g *generate.Generator, g.SetRootReadonly(s.ReadOnlyFilesystem) + noUseIPC := s.IpcNS.NSMode == specgen.FromContainer || s.IpcNS.NSMode == specgen.FromPod || s.IpcNS.NSMode == specgen.Host + noUseNet := s.NetNS.NSMode == specgen.FromContainer || s.NetNS.NSMode == specgen.FromPod || s.NetNS.NSMode == specgen.Host + noUseUTS := s.UtsNS.NSMode == specgen.FromContainer || s.UtsNS.NSMode == specgen.FromPod || s.UtsNS.NSMode == specgen.Host + // Add default sysctls defaultSysctls, err := util.ValidateSysctls(rtc.Sysctls()) if err != nil { @@ -186,20 +190,20 @@ func securityConfigureGenerator(s *specgen.SpecGenerator, g *generate.Generator, for sysctlKey, sysctlVal := range defaultSysctls { // Ignore mqueue sysctls if --ipc=host - if s.IpcNS.IsHost() && strings.HasPrefix(sysctlKey, "fs.mqueue.") { + if noUseIPC && strings.HasPrefix(sysctlKey, "fs.mqueue.") { logrus.Infof("Sysctl %s=%s ignored in containers.conf, since IPC Namespace set to host", sysctlKey, sysctlVal) continue } // Ignore net sysctls if --net=host - if s.NetNS.IsHost() && strings.HasPrefix(sysctlKey, "net.") { + if noUseNet && strings.HasPrefix(sysctlKey, "net.") { logrus.Infof("Sysctl %s=%s ignored in containers.conf, since Network Namespace set to host", sysctlKey, sysctlVal) continue } // Ignore uts sysctls if --uts=host - if s.UtsNS.IsHost() && (strings.HasPrefix(sysctlKey, "kernel.domainname") || strings.HasPrefix(sysctlKey, "kernel.hostname")) { + if noUseUTS && (strings.HasPrefix(sysctlKey, "kernel.domainname") || strings.HasPrefix(sysctlKey, "kernel.hostname")) { logrus.Infof("Sysctl %s=%s ignored in containers.conf, since UTS Namespace set to host", sysctlKey, sysctlVal) continue } -- cgit v1.2.3-54-g00ecf