[HIGH] Patch docker-cli for CVE-2026-17106

[v-swapsahu]

Merge Checklist

All boxes should be checked before merging the PR (just tick any boxes which don't apply to this PR)

• The toolchain has been rebuilt successfully (or no changes were made to it)
• The toolchain/worker package manifests are up-to-date
• Any updated packages successfully build (or no packages were changed)
• Packages depending on static components modified in this PR (Golang, *-static subpackages, etc.) have had their Release tag incremented.
• Package tests (%check section) have been verified with RUN_CHECK=y for existing SPEC files, or added to new SPEC files
• All package sources are available
• cgmanifest files are up-to-date and sorted (./cgmanifest.json, ./toolkit/scripts/toolchain/cgmanifest.json, .github/workflows/cgmanifest.json)
• LICENSE-MAP files are up-to-date (./LICENSES-AND-NOTICES/SPECS/data/licenses.json, ./LICENSES-AND-NOTICES/SPECS/LICENSES-MAP.md, ./LICENSES-AND-NOTICES/SPECS/LICENSE-EXCEPTIONS.PHOTON)
• All source files have up-to-date hashes in the *.signatures.json files
• sudo make go-tidy-all and sudo make go-test-coverage pass
• Documentation has been updated to match any changes to the build system
• Ready to merge

---

Summary

Patch docker-cli for CVE-2026-17106

Change Log

• SPECS/docker-cli/CVE-2026-17106.patch
• SPECS/docker-cli/docker-cli.spec

Does this affect the toolchain?

NO

Associated issues

• #xxxx

Links to CVEs

• https://nvd.nist.gov/vuln/detail/cve-2026-17106

Test Methodology

• Local Build

• Patch application during build

• Verification is done via a standalone POC
  A) WITH patch (current HEAD) — expect PASS

Expected: --- PASS for SymlinkBreakout, RejectsRelativeEscapeBeforeAbsoluteSymlink, HardlinkThroughAbsoluteSymlink → ok.

B) WITHOUT patch (vulnerable) — expect FAIL

How the PoC works:

the tar defines inner/go_up → .. and inner/go_up/escape → ../victim, then writes inner/go_up/escape/newfile.

• Unpatched extraction follows those archive-created symlinks and lands newfile in the sibling victim/ (outside dest).
• Patched code resolves intermediate components inside an os.Root, so the write stays confined (or is rejected).

[azure-pipelines]

Azure Pipelines:
There may be pipelines that require an authorized user to comment /azp run to run.

[v-swapsahu]

@microsoft-github-policy-service agree company="Microsoft"

[v-swapsahu]

Patch Analysis:
CVE-2026-17106: "CopyEscape" — tar-extraction symlink/hardlink path traversal

Backported: Yes

• Backport of moby/go-archive v0.3.1→v0.3.2 onto vendored github.com/docker/docker/pkg/archive. Replaces string checks with os.Root + resolveArchivePath (in-root intermediate-symlink resolution, final component preserved) + resolveHardlinkTarget/root.Link, and rejects non-local names via filepath.IsLocal. New rootpath.go (fsRootPath, forked from containerd/continuity) provides chroot-like resolution.

• Squashes 3 upstream commits: df55fdf3 (core hardening), 9e6d2c7c (absolute-symlink resolve-in-root), 4f6cd58f (hardlink through absolute symlink).

• sync.OnceValues is a generic (Go 1.21+); the man/go.mod manpages build is pinned to go1.16 and can't instantiate generics. Replaced by a plain memoized closure — three locals (absPathVal, absPathErr, absPathDone) with an absPath() func

• pathpkg "path": The path package is imported under the alias pathpkg to avoid colliding with the many local path variables in the extraction code.

Files NOT backported — and why

• copy.go, copy_test.go (RebaseArchiveEntries, upstream 8829a251/1c23372e)
  Non-security docker cp path-rebasing correctness change. Explicitly out of scope; stated in the patch header.

• Upstream test files (archive_test.go, archive_unix_test.go, utils_test.go, chrootarchive/...)
  Test scaffolding not carried into the vendored tree; package has no %check, so no test ships in the patch.

• time_* files (time.go/time_nonwindows.go/time_windows.go)
  Not needed. The existing time_linux.go / time_unsupported.go are kept unchanged; timestamps are handled inline through os.Root in archive.go/diff.go.

Verification
Local build passes. PoC: passes with patch, fails without patch.

Correctly scoped backport of the upstream containment fix; only the non-security RebaseArchiveEntries change and test files are omitted. No toolchain/build changes required on Azure Linux 3.0.

Pipelines - Run PR-18659+docker-cli+unknown has been triggered and it has passed.

Patch Application:

[azure-pipelines]

Azure Pipelines:
There may be pipelines that require an authorized user to comment /azp run to run.