Commit b0ca403a authored by Cedric Xing's avatar Cedric Xing Committed by Dan Williams
Browse files

tsm-mr: Fix init breakage after bin_attrs constification by scoping non-const... 


tsm-mr: Fix init breakage after bin_attrs constification by scoping non-const pointers to init phase

Commit 9bec9445 ("sysfs: constify attribute_group::bin_attrs") enforced
the ro-after-init principle by making elements of bin_attrs_new pointing to
const.

To align with this change, introduce a temporary variable `bap` within the
initialization loop. This improves code clarity by explicitly marking the
initialization scope and eliminates the need for type casts when assigning
to bin_attrs_new.

Signed-off-by: default avatarCedric Xing <cedric.xing@intel.com>
Link: https://patch.msgid.link/20250513164154.10109-1-cedric.xing@intel.com


Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent 1f450730

drivers/virt/coco/tsm-mr.c

+15 −15
Original line number Diff line number Diff line
@@ -173,7 +173,7 @@ tsm_mr_create_attribute_group(const struct tsm_measurements *tm) 
	 * so that we don't have to free MR names one-by-one in

	 * tsm_mr_free_attribute_group()

	 */

	const struct bin_attribute * const *attrs __free(kfree) =

	const struct bin_attribute **attrs __free(kfree) =

		kzalloc(sizeof(*attrs) * (tm->nr_mrs + 1) + nlen, GFP_KERNEL);

	struct tm_context *ctx __free(kfree) =

		kzalloc(struct_size(ctx, mrs, tm->nr_mrs), GFP_KERNEL);
@@ -187,16 +187,14 @@ tsm_mr_create_attribute_group(const struct tsm_measurements *tm) 
	end = name + nlen;



	for (size_t i = 0; i < tm->nr_mrs; ++i) {

		/* break const for init */

		struct bin_attribute **bas = (struct bin_attribute **)attrs;

		struct bin_attribute *bap = &ctx->mrs[i];



		bas[i] = &ctx->mrs[i];

		sysfs_bin_attr_init(bas[i]);

		sysfs_bin_attr_init(bap);



		if (tm->mrs[i].mr_flags & TSM_MR_F_NOHASH)

			bas[i]->attr.name = tm->mrs[i].mr_name;

			bap->attr.name = tm->mrs[i].mr_name;

		else if (name < end) {

			bas[i]->attr.name = name;

			bap->attr.name = name;

			name += snprintf(name, end - name, "%s:%s",

					 tm->mrs[i].mr_name,

					 hash_algo_name[tm->mrs[i].mr_hash]);
@@ -206,21 +204,23 @@ tsm_mr_create_attribute_group(const struct tsm_measurements *tm) 


		/* check for duplicated MR definitions */

		for (size_t j = 0; j < i; ++j)

			if (!strcmp(bas[i]->attr.name, bas[j]->attr.name))

			if (!strcmp(bap->attr.name, attrs[j]->attr.name))

				return ERR_PTR(-EINVAL);



		if (tm->mrs[i].mr_flags & TSM_MR_F_READABLE) {

			bas[i]->attr.mode |= 0444;

			bas[i]->read_new = tm_digest_read;

			bap->attr.mode |= 0444;

			bap->read_new = tm_digest_read;

		}



		if (tm->mrs[i].mr_flags & TSM_MR_F_WRITABLE) {

			bas[i]->attr.mode |= 0200;

			bas[i]->write_new = tm_digest_write;

			bap->attr.mode |= 0200;

			bap->write_new = tm_digest_write;

		}



		bas[i]->size = tm->mrs[i].mr_size;

		bas[i]->private = ctx;

		bap->size = tm->mrs[i].mr_size;

		bap->private = ctx;



		attrs[i] = bap;

	}



	if (name != end)
@@ -244,7 +244,7 @@ EXPORT_SYMBOL_GPL(tsm_mr_create_attribute_group); 
void tsm_mr_free_attribute_group(const struct attribute_group *attr_grp)

{

	if (!IS_ERR_OR_NULL(attr_grp)) {

		kfree(attr_grp->bin_attrs);

		kfree(attr_grp->bin_attrs_new);

		kfree(container_of(attr_grp, struct tm_context, agrp));

	}

}