While buildkitd needs to run as root (since both workers currently imply that)
there's no reason to enforce running the client as root, it works just fine (in
my slightly limited testing) as non-root so long as it has access to the sock
Signed-off-by: Ian Campbell <ijc@docker.com>
e.g. with busybox image:
OCI runtime create failed: container_linux.go:348:
starting container process caused "process_linux.go:402:
container init caused \"rootfs_linux.go:58:
mounting \\\"proc\\\" to rootfs \\\"/.../rootfs\\\" at \\\"/proc\\\"
caused \\\"mkdir /.../rootfs/proc: read-only file system\\\"\"": unknown
This is because we were setting the underlying snapshot readonly so the various
mountpoints (here /proc) cannot be created. This would not be necessary if
those mountpoints were present in images but they typically are not.
The right way to get around this (used e.g. by `ctr`) is to use a writeable
snapshot but to set root readonly in the OCI spec. In this configuration the
rootfs is writeable when mounts are processed but is then made readonly by the
runtime (runc) just before entering the user specified binary within the
container.
This involved a surprising amount of plumbing.
Use this new found ability in the dockerfile converter's `dispatchCopy`
function.
Signed-off-by: Ian Campbell <ijc@docker.com>
Modelled after the vendor support provide a validator and an updator for files
produced by `go generate` (which today just means `*.pb.go`).
Main difference from the vendor support is that we are no longer simply nuking
and replacing a single directory, so I ended up hardcoding `*.pb.go` in a bunch
of places which I don't like but cannot see a way around which doesn't risk
nuking people's other local changes.
The generated files are placed in an unpacked form in a `FROM scratch`
container for update. Use a subdirectory and `tar --strip-components` (portable
to MacOS and Linux according to `tar(1)`) since trying to do a `docker export`
of just the root ends up adding `.dockerenv`, `sys`, `proc` and `dev` to the
source tree.
The validate container is not `FROM scratch` because we want `cat`.
The run in `frontend/gateway/pb/generate.go` was missing an include so fix
that.
The versions of `protoc` and the gogo plugins were chosen to regenerate the
existing code as closely as possible. The updates to `*.pg.go` here are all the
result of regenerating with go1.9 which fixed
https://github.com/golang/go/issues/17663 and replaced an invalid timestamp in
the gzip header of the data encoded in `fileDescriptor*`, and adopted a new
standard for marking generated files.
Finally, I noticed that my `docker run`s were missing an `--rm` which I
inherited from `validate-vendor`, so fix all those.
Closes: #322
Signed-off-by: Ian Campbell <ijc@docker.com>