core: pager: refactored to fix NULL dereferencing

assert not NULL before dereferencing in tee_pager_add_core_area(). Signed-off-by: Sander Visser <[email protected]> Reviewed-by: Jens Wiklander <[email protected]> Reviewed-by: Etienne Carriere <[email protected]>
gagachang · Jun 29, 2020 · 3f37fff · 3f37fff
1 parent b2b2762
commit 3f37fff
Showing 1 changed file with 4 additions and 4 deletions.
diff --git a/core/arch/arm/mm/tee_pager.c b/core/arch/arm/mm/tee_pager.c
@@ -532,9 +532,12 @@ void tee_pager_add_core_area(vaddr_t base, enum tee_pager_area_type type,
 	uint32_t flags = 0;
 	size_t fobj_pgoffs = 0;
 	vaddr_t b = base;
-	size_t s = fobj->num_pages * SMALL_PAGE_SIZE;
+	size_t s = 0;
 	size_t s2 = 0;
 
+	assert(fobj);
+	s = fobj->num_pages * SMALL_PAGE_SIZE;
+
 	DMSG("0x%" PRIxPTR " - 0x%" PRIxPTR " : type %d", base, base + s, type);
 
 	if (base & SMALL_PAGE_MASK || !s) {
@@ -554,9 +557,6 @@ void tee_pager_add_core_area(vaddr_t base, enum tee_pager_area_type type,
 		panic();
 	}
 
-	if (!fobj)
-		panic();
-
 	while (s) {
 		s2 = MIN(CORE_MMU_PGDIR_SIZE - (b & CORE_MMU_PGDIR_MASK), s);
 		area = calloc(1, sizeof(*area));