Fix/PLT 406 param list clear function clears local parameter

[jeanbaptistelab]

Local parameters (whose node == 0) are usually placed in a specific “param” ELF section and are read-only.

In module code, remote parameters are added to a linked list, independent of the of the read-only “param” ELF section.

However, in CSH context, APMs that define their own parameters, add those parameters to the linked-list during initialization (by calling param_list_add()). Those parameters are in essence local not remote (they are part of the CSH instance local parameters).

When some code calls the param_list_clear() function (for instance from hk_store.c, part of OBC House Keeping), the linked list is essentially reset, causing the list of CSH parameters to revert back to the list as it was before loading any APM.

[Copilot]

Pull request overview

Fixes PLT-406 by changing param_list_clear() semantics so it does not wipe “local” parameters that are dynamically added with node == 0 (e.g., CSH/APM-defined params), and adds a regression test to validate the behavior.

Changes:

• Update param_list_clear() to only clear non-local (node != 0) entries from the dynamic list.
• Add a new plt_406 test exercising the clear/remove behavior for node==0 vs node!=0 parameters.
• Minor test/build updates (fix plt_405 exit code; register new test in Meson).

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
tests/plt_406.c	Adds a regression test covering PLT-406 behavior around param_list_clear() and parameter persistence.
tests/plt_405.c	Fixes test program to return success (0) on pass.
tests/meson.build	Registers the new plt_406 test executable.
src/param/list/param_list.c	Changes param_list_clear() to preserve node==0 list entries while clearing node!=0 entries.
meson.build	Simplifies dependency list selection for the param library build.

Comments suppressed due to low confidence (1)

tests/plt_406.c:30

• Same as above: check the return value of param_list_create_remote before using it.

    remote = param_list_create_remote(128, 400, PARAM_TYPE_UINT16, PM_DEBUG, 0, "remote", NULL, NULL, -1);
    param_list_add(remote);

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Comments suppressed due to low confidence (2)

src/param/list/param_list.c:421

• param_list_clear() currently removes elements while iterating with SLIST_FOREACH and then calls param_list_destroy() on a stack copy of the element. This can lead to use-after-free in the loop increment and can also attempt to free() stack memory (because param_list_destroy_impl() frees the param pointer itself in dynamic mode). Iterate safely by caching next, remove the real element, and destroy the real pointer.

	SLIST_FOREACH(iter, &param_list_head, next) {
		if(*iter->node != 0) {
			SLIST_REMOVE(&param_list_head, iter, param_s, next);
			struct param_s to_be_destroyed = *iter;
			param_list_destroy(&to_be_destroyed);

tests/plt_406.c:24

• This assertion checks p (the previously found local param) instead of remote. If param_list_create_remote() fails, param_list_add(remote) will dereference NULL.

    assert(p);

[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.