On Thu, 31. Oct 20:31, George Rurikov wrote:

When support for PCC Opregion was added, validation of field_obj was missed. Based on the acpi_ev_address_space_dispatch function description, field_obj can be NULL, and also when acpi_ev_address_space_dispatch is called in the acpi_ex_region_read() NULL is passed as field_obj.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 0acf24ad7e10 ("ACPICA: Add support for PCC Opregion special context data") Cc: stable@vger.kernel.org Signed-off-by: George Rurikov grurikov@gmail.com

---

drivers/acpi/acpica/evregion.c | 18 +++++++++++-------

Hi George,

ACPICA patches go first via a separate Github project [1]. [1]: https://github.com/acpica/acpica

Please see [2] and [3] for more info: [2]: https://lore.kernel.org/acpica-devel/CAJZ5v0i7LYzF13M0qdeYWXZ7uO6HUpAS7pE5RJ... [3]: https://docs.kernel.org/driver-api/acpi/linuxized-acpica.html

1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/acpi/acpica/evregion.c b/drivers/acpi/acpica/evregion.c index cf53b9535f18..03e8b6f186af 100644 --- a/drivers/acpi/acpica/evregion.c +++ b/drivers/acpi/acpica/evregion.c @@ -164,13 +164,17 @@ acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj, } if (region_obj->region.space_id == ACPI_ADR_SPACE_PLATFORM_COMM) {

• 	struct acpi_pcc_info *ctx =
  

• 	    handler_desc->address_space.context;
  

• 	ctx->internal_buffer =
  

• 	    field_obj->field.internal_pcc_buffer;
  

• 	ctx->length = (u16)region_obj->region.length;
  

• 	ctx->subspace_id = (u8)region_obj->region.address;
  

• 	if (field_obj != NULL) {
  

• 		struct acpi_pcc_info *ctx =
  

• 			handler_desc->address_space.context;
  

• 		ctx->internal_buffer =
  

• 			field_obj->field.internal_pcc_buffer;
  

• 		ctx->length = (u16)region_obj->region.length;
  

• 		ctx->subspace_id = (u8)region_obj->region.address;
  

• 	} else {
  

• 		return_ACPI_STATUS(AE_ERROR);
  

• 	}
  

  }

if (region_obj->region.space_id == -- 2.34.1