bpf: Switch to krealloc_array()

Let the krealloc_array() copy the original data and
check for a multiplication overflow.

Signed-off-by: Andy Shevchenko <[e-mail]>
Signed-off-by: Andrii Nakryiko <[e-mail]>
Acked-by: Yonghong Song <[e-mail]>
Link: https://lore.kernel.org/bpf/[e-mail]

kernel/bpf/core.c

···
 		return -EINVAL;
 	}
 
-	tab = krealloc(tab, size * sizeof(*poke), GFP_KERNEL);
+	tab = krealloc_array(tab, size, sizeof(*poke), GFP_KERNEL);
 	if (!tab)
 		return -ENOMEM;