6.12-stable review patch. If anyone has any objections, please let me know.
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From: Mario Limonciello mario.limonciello@amd.com
[ Upstream commit 8e81b9cd6e95188d12c9cc25d40b61dd5ea05ace ]
commit 376a8c2a14439 ("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: Christian Heusel christian@heusel.eu Closes: https://lore.kernel.org/platform-driver-x86/ae644428-5bf2-4b30-81ba-0b259ed3... Fixes: 376a8c2a14439 ("platform/x86/amd/pmf: Update PMF Driver for Compatibility with new PMF-TA") Signed-off-by: Mario Limonciello mario.limonciello@amd.com Tested-by: Christian Heusel christian@heusel.eu Link: https://lore.kernel.org/r/20250423132002.3984997-3-superm1@kernel.org Reviewed-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/platform/x86/amd/pmf/tee-if.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/drivers/platform/x86/amd/pmf/tee-if.c b/drivers/platform/x86/amd/pmf/tee-if.c index 804c4085b82fb..b6bcc1d57f968 100644 --- a/drivers/platform/x86/amd/pmf/tee-if.c +++ b/drivers/platform/x86/amd/pmf/tee-if.c @@ -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);