fix(smccc): ensure that mpidr passed through SMC is valid
There are various SMC calls which pass mpidr as an argument which is
currently tested at random places in SMC call path.
To make the mpidr validation check consistent across SMC calls, do
this check as part of SMC argument validation.
This patch introduce a helper function is_valid_mpidr() to validate
mpidr and call it as part of validating SMC arguments at starting of
SMC handlers (which expect mpidr as an argument).
Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
Change-Id: I11ea50e22caf17896cf4b2059b87029b2ba136b1
(cherry picked from commit e60c18471fc7488cc0bf1dc7eae3b43be77045a4)
diff --git a/include/plat/common/platform.h b/include/plat/common/platform.h
index 8407bbd..472ed34 100644
--- a/include/plat/common/platform.h
+++ b/include/plat/common/platform.h
@@ -72,6 +72,20 @@
int plat_core_pos_by_mpidr(u_register_t mpidr);
int plat_get_mbedtls_heap(void **heap_addr, size_t *heap_size);
+/*******************************************************************************
+ * Simple routine to determine whether a mpidr is valid or not.
+ ******************************************************************************/
+static inline bool is_valid_mpidr(u_register_t mpidr)
+{
+ int pos = plat_core_pos_by_mpidr(mpidr);
+
+ if ((pos < 0) || ((unsigned int)pos >= PLATFORM_CORE_COUNT)) {
+ return false;
+ }
+
+ return true;
+}
+
#if STACK_PROTECTOR_ENABLED
/*
* Return a new value to be used for the stack protection's canary.