Commit 317e94be44d64cf0 introduced a local variable err, which masked
the err used as a named return value. As a result, any relabeling error
(happened in that defer) is not returned, and the caller gets "", nil,
moving on to performing a bind mount with empty m.Source argument
(which, apparently, results in mounting a current directory).
This can be reproduced by trying to add a bind mount which has no space
left (see RHBZ link below for details).
rhatdan
commented
2 years ago
Commit 317e94be44d64cf0 introduced a local variable err, which masked the err used as a named return value. As a result, any relabeling error (happened in that defer) is not returned, and the caller gets
"", nil, moving on to performing a bind mount with empty m.Source argument (which, apparently, results in mounting a current directory).This can be reproduced by trying to add a bind mount which has no space left (see RHBZ link below for details).
This issue was spotted upstream during the review, and fixed before the merge (see https://github.com/moby/moby/pull/34792#issuecomment-330355030). In this repository, though, it was never fixed.
Fixes: https://bugzilla.redhat.com/1878621