[kvm-unit-tests PATCH v2] alloc: Add memalign error checks

[Janosch Frank <frankja@linux.ibm.com>]

Let's test for size and alignment in memalign to catch invalid input
data. Also we need to test for NULL after calling the memalign
function of the registered alloc operations.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
---
 lib/alloc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/alloc.c b/lib/alloc.c
index ecdbbc4..b763c70 100644
--- a/lib/alloc.c
+++ b/lib/alloc.c
@@ -47,6 +47,8 @@ void *memalign(size_t alignment, size_t size)
 	uintptr_t mem;
 
 	assert(alloc_ops && alloc_ops->memalign);
+	if (!size || !alignment)
+		return NULL;
 	if (alignment <= sizeof(uintptr_t))
 		alignment = sizeof(uintptr_t);
 	else
@@ -55,6 +57,7 @@ void *memalign(size_t alignment, size_t size)
 	blkalign = MAX(alignment, alloc_ops->align_min);
 	size = ALIGN(size + METADATA_EXTRA, alloc_ops->align_min);
 	p = alloc_ops->memalign(blkalign, size);
+	assert(p);
 
 	/* Leave room for metadata before aligning the result.  */
 	mem = (uintptr_t)p + METADATA_EXTRA;
-- 
2.20.1