[PATCH 2/3][next] lib/stackdepot.c: Use flex_array_size() helper in memcpy()

[Gustavo A. R. Silva]

Make use of the flex_array_size() helper to calculate the size of a
flexible array member within an enclosing structure.

This helper offers defense-in-depth against potential integer
overflows, while at the same time makes it explicitly clear that
we are dealing with a flexible array member.

Signed-off-by: Gustavo A. R. Silva <gustavo...@kernel.org>
---
 lib/stackdepot.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index c6106cfb7950..683b6a8ddade 100644
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -135,7 +135,7 @@ static struct stack_record *depot_alloc_stack(unsigned long 
*entries, int size,
        stack->handle.slabindex = depot_index;
        stack->handle.offset = depot_offset >> STACK_ALLOC_ALIGN;
        stack->handle.valid = 1;
-       memcpy(stack->entries, entries, size * sizeof(unsigned long));
+       memcpy(stack->entries, entries, flex_array_size(stack, entries, size));
        depot_offset += required_size;
 
        return stack;
-- 
2.27.0