arm64: acpi: Fix possible memory leak of ffh_ctxt

Allocated 'ffh_ctxt' memory leak is possible if the SMCCC version
and conduit checks fail and -EOPNOTSUPP is returned without freeing the
allocated memory.

Fix the same by moving the allocation after the SMCCC version and
conduit checks.

Fixes: 1d280ce0 ("arm64: Add architecture specific ACPI FFH Opregion callbacks")
Cc: <stable@vger.kernel.org> # 6.2.x
Cc: Will Deacon <will@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Suggested-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/r/202302191417.dAl9NuE8-lkp@intel.com/Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20230223135742.2952091-1-sudeep.holla@arm.comSigned-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/kernel/acpi.c

@@ -435,10 +435,6 @@ int acpi_ffh_address_space_arch_setup(void *handler_ctxt, void **region_ctxt)
 	enum arm_smccc_conduit conduit;
 	struct acpi_ffh_data *ffh_ctxt;
 
-	ffh_ctxt = kzalloc(sizeof(*ffh_ctxt), GFP_KERNEL);
-	if (!ffh_ctxt)
-		return -ENOMEM;
-
 	if (arm_smccc_get_version() < ARM_SMCCC_VERSION_1_2)
 		return -EOPNOTSUPP;
 
@@ -448,6 +444,10 @@ int acpi_ffh_address_space_arch_setup(void *handler_ctxt, void **region_ctxt)
 		return -EOPNOTSUPP;
 	}
 
+	ffh_ctxt = kzalloc(sizeof(*ffh_ctxt), GFP_KERNEL);
+	if (!ffh_ctxt)
+		return -ENOMEM;
+
 	if (conduit == SMCCC_CONDUIT_SMC) {
 		ffh_ctxt->invoke_ffh_fn = __arm_smccc_smc;
 		ffh_ctxt->invoke_ffh64_fn = arm_smccc_1_2_smc;