libnvdimm: Annotate struct nd_region with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct nd_region.
Additionally, since the element count member must be set before accessing
the annotated flexible array member, move its initialization earlier.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: nvdimm@lists.linux.dev
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
This commit is contained in:
Kees Cook 2023-09-22 10:52:39 -07:00 committed by Ira Weiny
parent 36c75ce3bd
commit fd86eff338
2 changed files with 2 additions and 2 deletions

View File

@ -422,7 +422,7 @@ struct nd_region {
struct nd_interleave_set *nd_set;
struct nd_percpu_lane __percpu *lane;
int (*flush)(struct nd_region *nd_region, struct bio *bio);
struct nd_mapping mapping[];
struct nd_mapping mapping[] __counted_by(ndr_mappings);
};
static inline bool nsl_validate_nlabel(struct nd_region *nd_region,

View File

@ -1028,6 +1028,7 @@ static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
if (!nd_region)
return NULL;
nd_region->ndr_mappings = ndr_desc->num_mappings;
/* CXL pre-assigns memregion ids before creating nvdimm regions */
if (test_bit(ND_REGION_CXL, &ndr_desc->flags)) {
nd_region->id = ndr_desc->memregion;
@ -1062,7 +1063,6 @@ static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
get_device(&nvdimm->dev);
}
nd_region->ndr_mappings = ndr_desc->num_mappings;
nd_region->provider_data = ndr_desc->provider_data;
nd_region->nd_set = ndr_desc->nd_set;
nd_region->num_lanes = ndr_desc->num_lanes;