openssl_pkcs12: fix crash when trying to get non-existing other certificates

[felixfontein]

SUMMARY

Fixes #486.

ISSUE TYPE

• Bugfix Pull Request

COMPONENT NAME

openssl_pkcs12

[patchback]

Backport to stable-1: 💔 cherry-picking failed — conflicts found

❌ Failed to cleanly apply 9ed4526 on top of patchback/backports/stable-1/9ed4526fee894c7a947e305afdf63b58debf41f3/pr-487

Backporting merged PR #487 into main

1. Ensure you have a local repo clone of your fork. Unless you cloned it
   from the upstream, this would be your origin remote.
2. Make sure you have an upstream repo added as a remote too. In these
   instructions you'll refer to it by the name upstream. If you don't
   have it, here's how you can add it:

   $ git remote add upstream https://github.com/ansible-collections/community.crypto.git

3. Ensure you have the latest copy of upstream and prepare a branch
   that will hold the backported code:

   $ git fetch upstream
   $ git checkout -b patchback/backports/stable-1/9ed4526fee894c7a947e305afdf63b58debf41f3/pr-487 upstream/stable-1

4. Now, cherry-pick PR openssl_pkcs12: fix crash when trying to get non-existing other certificates #487 contents into that branch:

   $ git cherry-pick -x 9ed4526fee894c7a947e305afdf63b58debf41f3

   If it'll yell at you with something like fatal: Commit 9ed4526fee894c7a947e305afdf63b58debf41f3 is a merge but no -m option was given., add -m 1 as follows intead:

   $ git cherry-pick -m1 -x 9ed4526fee894c7a947e305afdf63b58debf41f3

5. At this point, you'll probably encounter some merge conflicts. You must
   resolve them in to preserve the patch from PR openssl_pkcs12: fix crash when trying to get non-existing other certificates #487 as close to the
   original as possible.
6. Push this branch to your fork on GitHub:

   $ git push origin patchback/backports/stable-1/9ed4526fee894c7a947e305afdf63b58debf41f3/pr-487

7. Create a PR, ensure that the CI is green. If it's not — update it so that
   the tests and any other checks pass. This is it!
   Now relax and wait for the maintainers to process your pull request
   when they have some cycles to do reviews. Don't worry — they'll tell you if
   any improvements are necessary when the time comes!

🤖 @patchback
I'm built with octomachinery and
my source is open — https://github.com/sanitizers/patchback-github-app.

[felixfontein]

@briantist thanks for reviewing this one as well :)

[felixfontein]

Backport to stable-1 in #488.