Unverified Commit 8e81b9cd authored by Mario Limonciello's avatar Mario Limonciello Committed by Ilpo Järvinen
Browse files

drivers/platform/x86/amd: pmf: Check for invalid Smart PC Policies 



commit 376a8c2a ("platform/x86/amd/pmf: Update PMF Driver for
Compatibility with new PMF-TA") added support for platforms that support
an updated TA, however it also exposed a number of platforms that although
they have support for the updated TA don't actually populate a policy
binary.

Add an explicit check that the policy binary isn't empty before
initializing the TA.

Reported-by: default avatarChristian Heusel <christian@heusel.eu>
Closes: https://lore.kernel.org/platform-driver-x86/ae644428-5bf2-4b30-81ba-0b259ed3449b@heusel.eu/


Fixes: 376a8c2a ("platform/x86/amd/pmf: Update PMF Driver for Compatibility with new PMF-TA")
Signed-off-by: default avatarMario Limonciello <mario.limonciello@amd.com>
Tested-by: default avatarChristian Heusel <christian@heusel.eu>
Link: https://lore.kernel.org/r/20250423132002.3984997-3-superm1@kernel.org


Reviewed-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
parent 690d722e

drivers/platform/x86/amd/pmf/tee-if.c

+16 −0
Original line number Diff line number Diff line
@@ -334,6 +334,11 @@ static int amd_pmf_start_policy_engine(struct amd_pmf_dev *dev) 
	return 0;

}



static inline bool amd_pmf_pb_valid(struct amd_pmf_dev *dev)

{

	return memchr_inv(dev->policy_buf, 0xff, dev->policy_sz);

}



#ifdef CONFIG_AMD_PMF_DEBUG

static void amd_pmf_hex_dump_pb(struct amd_pmf_dev *dev)

{
@@ -361,6 +366,11 @@ static ssize_t amd_pmf_get_pb_data(struct file *filp, const char __user *buf, 
	dev->policy_buf = new_policy_buf;

	dev->policy_sz = length;



	if (!amd_pmf_pb_valid(dev)) {

		ret = -EINVAL;

		goto cleanup;

	}



	amd_pmf_hex_dump_pb(dev);

	ret = amd_pmf_start_policy_engine(dev);

	if (ret < 0)
@@ -533,6 +543,12 @@ int amd_pmf_init_smart_pc(struct amd_pmf_dev *dev) 


	memcpy_fromio(dev->policy_buf, dev->policy_base, dev->policy_sz);



	if (!amd_pmf_pb_valid(dev)) {

		dev_info(dev->dev, "No Smart PC policy present\n");

		ret = -EINVAL;

		goto err_free_policy;

	}



	amd_pmf_hex_dump_pb(dev);



	dev->prev_data = kzalloc(sizeof(*dev->prev_data), GFP_KERNEL);