Using s3 gives: insufficient_scope: authorization failed

[AbdealiLoKo]

I am trying the s3 cache backend , and I keep getting an authorization failed error even though I seem to have the right authorization

$ docker buildx create --name builder --bootstrap --use --driver docker-container --driver-opt "image=moby/buildkit:master"

# I first tried this as I had the env variables present for awscli
$ docker buildx build --push \
  --cache-to type=s3,region=us-west-2,bucket=MYBUCKET \
  --cache-from type=s3,region=us-west-2,bucket=MYBUCKET \
  --tag mytag .

# And also tried explicitly giving the id/key:
$ docker buildx build --push \
  --cache-to type=s3,region=us-west-2,bucket=MYBUCKET,access_key_id=$AWS_ACCESS_KEY_ID,secret_access_key=$AWS_SECRET_ACCESS_KEY \
  --cache-from type=s3,region=us-west-2,bucket=MYBUCKET,access_key_id=$AWS_ACCESS_KEY_ID,secret_access_key=$AWS_SECRET_ACCESS_KEY \
  --tag mytag .

The following works fine:

$ echo test > /tmp/test
$ aws s3 cp /tmp/test s3://MYBUCKET/test
Completed 5 Bytes/5 Bytes (1 Bytes/s) with 1 file(s) remaiupload: ../tmp/test to s3://MYBUCKET/test
$ aws s3 ls s3://MYBUCKET/
2022-11-24 00:45:53          5 test

When I do $ env | grep AWS it does show me that both the values are set

My Dockerfile is:

FROM alpine
RUN echo test1
RUN echo test2

And the error I get is:

[+] Building 23.1s (8/8) FINISHED
 => [internal] load build definition from Dockerfile                                                      0.1s
 => => transferring dockerfile: 3.59kB                                                                    0.0s
 => [internal] load metadata for docker.io/library/alpine:latest                                         10.6s
 => importing cache manifest from s3:11920486102485180003                                                 1.1s
 => [1/3] FROM docker.io/library/alpine@sha256:8914eb54f968791faf6a8638949e480fef81e697984fba772b3976835  1.7s
 => => resolve docker.io/library/alpine@sha256:8914eb54f968791faf6a8638949e480fef81e697984fba772b3976835  0.0s
 => => sha256:c158987b05517b6f2c5913f3acef1f2182a32345a304fe357e3ace5fadcad715 3.37MB / 3.37MB            1.5s
 => => extracting sha256:c158987b05517b6f2c5913f3acef1f2182a32345a304fe357e3ace5fadcad715                 0.1s
 => [2/3] RUN echo test1                                                                                  0.1s
 => [3/3] RUN echo test2                                                                                  0.1s
 => ERROR exporting to image                                                                              9.3s
 => => exporting layers                                                                                   0.3s
 => => exporting manifest sha256:8e5631dfe467d43dce17f835a522962598bf3bec5ab7c17f4e33c1a0ad0bde49         0.0s
 => => exporting config sha256:282d4d5a05f3c38893048f0052d3d3169dec65019a29154db98a4ada9720202d           0.0s
 => => pushing layers                                                                                     8.9s
------
 > exporting to image:
------
ERROR: failed to solve: failed to push mytag: server message: insufficient_scope: authorization failed

[crazy-max]

=> ERROR exporting to image

That doesn't look related to cache export but the image.