opencontainers
Allow shared mounts by default
The current behavior disallows any mount having (r)shared on it because by default, the root is set with MS_SLAVE|MS_REC, which disallows sub-dirs from having a different propagation.
Projects have been working around this by setting the RootfsPropogation to "shared", to override the default (https://github.com/containerd/nerdctl/blob/main/pkg/mountutil/mountutil_linux.go#L185-L193).
This patch makes a reasonable attempt to make the functionality work without touching RootfsPropogation.
Looking at the code I've edited, the code resets it to PRIVATE below. Can someone chime in on what the code setting to SLAVE is meant to do? Totally likely my change isn't right because I'm not sure I understand what the purpose is of setting SLAVE is.
Just curious, why not set the propagation you want for the rootfs in the config.json, as nerdctl is doing in the link you point?
Can someone chime in on what the code setting to SLAVE is meant to do?
I guess @kolyshkin or @cyphar are the right persons to answer this