linux: `do_mount()` returns `fd` instead of `ms_move_fd`

[eriksjolund]

Claude Sonnet 5 pointed out that do_mount() returns fd instead of ms_move_fd here

crun/src/libcrun/linux.c

Lines 1425 to 1427 in fb54bc0

	ms_move_fd = open_mount_target (container, target, err);
	if (UNLIKELY (ms_move_fd < 0))
	return fd;

Click here for details about my Claude Sonnet 5 interaction

I got the idea that I could ask Claude Sonnet 5 to find some bugs. (Usually I have been using tools like less and git grep when searching for bugs).

In the web interface https://claude.ai/ I wrote

I wrote a patch for the crun project:
https://github.com/containers/crun/pull/2127/changes/83e7e40f0831780086a8faa625e4f499e6491907
Do you see any need for adding more crun_error_get_errno() in the crun source code?

A lot of text was generated but no bugs were found. The text ended with:

If you want, I can look at a specific area of the code (mounts, cgroups, seccomp, etc.) more deeply rather than a repo-wide grep pass.

I then entered

If you want, I can look at a specific area of the code (mounts, cgroups, seccomp, etc.) more deeply rather than a repo-wide grep pass.

yes, check mounts

Claude Sonnet 5 did not find any bugs related to crun_error_get_errno() but pointed out an unrelated bug about do_mount() returning fd instead of ms_move_fd.