From: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx> Subject: lib/stackdepot.c: use flex_array_size() helper in memcpy() 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. Link: https://lkml.kernel.org/r/186e37fe07196ee41a0e562fa8a8cb7a01112ec5.1601565471.git.gustavoars@xxxxxxxxxx Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/stackdepot.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/lib/stackdepot.c~lib-stackdepotc-use-flex_array_size-helper-in-memcpy +++ a/lib/stackdepot.c @@ -135,7 +135,7 @@ static struct stack_record *depot_alloc_ 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; _
