fix(macOS): prevent self-referential ~/.aws/.aws symlink#1778
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The VM-provisioning line appended to the guest's ~/.bashrc used
`ln -fs "$AWS_DIR" /root/.aws`. Without -n, when /root/.aws already
exists as a symlink to a directory, `ln -s` dereferences it and creates
the link *inside* the target instead of replacing it, surfacing on the
host through the writable home mount as a self-referential link:
~/.aws/.aws -> ~/.aws
This breaks recursive traversal of ~/.aws (e.g. `cp -r ~/.aws` aborts
with "directory causes a cycle"). The guard `[ -L /root/.aws ]` does not
prevent re-firing because it runs as the unprivileged VM user against
root-owned /root (0700), so the stat fails and the test is always false.
Add -n (--no-dereference) so repeated runs replace the symlink in place
instead of nesting, making the operation idempotent.
Signed-off-by: ecmiram <[email protected]>
ayush-panta
approved these changes
Jul 1, 2026
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Issue #, if available: Reported and confirmed in the runfinch community Slack #finch-interest:
Description of changes:
The line added to the guest's ~/.bashrc uses:
Two problems compound here:
Without
-n, when/root/.awsis already a symlink to a directory,ln -sdereferences it and nests the new link inside the target.On the host (via the writable home mount) this surfaces as:
which breaks recursive traversal of
~/.aws— e.g.cp -r ~/.awsaborts with "directory causes a cycle".
The
[ -L /root/.aws ]guard doesn't prevent re-firing: it runs as theunprivileged VM user against root-owned
/root(0700), so the statfails and the test is always false — the
lnruns on every shell.Adding
-n(--no-dereference) makes the link replacement idempotent, sorepeated runs replace the symlink in place instead of nesting.
Testing done:
Reproduced end-to-end, then verified in an isolated dev VM that the patched
binary writes
ln -fsnand~/.aws/.awsno longer regenerates (credspreserved).
make test-unit+golangci-lintpass.License Acceptance
By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.