latest and 0.14.6 fail when using COPY

[meezaan]

Describe the bug

Both latest and 0.14.6 are failing when using copy. For example:

Dockerfile:4
--------------------
   2 |     
   3 |     # Copy files
   4 | >>> COPY . /var/www/
   5 |     # COPY etc/apache2/mods-enabled/mpm_prefork.conf /etc/apache2/mods-enabled/mpm_prefork.conf
   6 |     COPY etc/unit/.unit.conf.json /docker-entrypoint.d/.unit.conf.json
--------------------
error: failed to solve: failed to compute cache key: failed to copy: httpReadSeeker.ReadAt: failed to open at offset 1048576: gzip: invalid header
FATA[0006] failed to build: build: exit status 1        
FATA[0006] failed to run task: exit status 1            

Things work fine if I use an older image like 0.14.4 or 0.14.5.

Reproduction steps

1. Create a Dockerfile with that copies files into the image.
2. Try and build using this resource.
3. See the above error.
   ...

Expected behavior

That builds do not fail with the invalid gzip header.

Additional context

No response

[taylorsilva]

We use COPY in this Dockerfile: https://github.com/concourse/ci/blob/master/tasks/build-resource-types-image/Dockerfile

Latest build of that image succeeded without issue using 0.14.6:

https://ci.concourse-ci.org/teams/main/pipelines/concourse/jobs/resource-types-images/builds/4829

Do you have a Dockerfile we can use to reproduce?

[meezaan]

Yes, here is the Dockerfile that throws the error.

FROM 1x.ax/mamluk/php/8.4:unit

# Copy files
COPY . /var/www/

COPY etc/unit/.unit.conf.json /docker-entrypoint.d/.unit.conf.json

# Run Composer
RUN export COMPOSER_ALLOW_SUPERUSER=1 && cd /var/www && composer install --no-dev

# Delete stuff we do not need
RUN rm -rf /var/www/.git
RUN rm -rf /var/www/.gitignore

This file builds fine on 0.14.5.

[taylorsilva]

Looks like a buildkit issue: moby/buildkit#6359

Buildkit just released a patch with this one fix: moby/buildkit#6366
Which is now in our automatically published 0.14.7: https://github.com/concourse/oci-build-task/releases/tag/v0.14.7

Can you try building with 0.14.7 and report back if it works now or not?

[meezaan]

Yes, issue fixed in 0.14.7. Thank you @taylorsilva.