cxgb4: smt: use struct_size() in kvzalloc()

One of the more common cases of allocation size calculations is
finding the size of a structure that has a zero-sized array at
the end, along with memory for some number of elements for that
array. For example:

struct foo {
    int stuff;
    struct boo entry[];
};

instance = kvzalloc(sizeof(struct foo) + count * sizeof(struct boo), GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can now
use the new struct_size() helper:

instance = kvzalloc(struct_size(instance, entry, count), GFP_KERNEL);

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/chelsio/cxgb4/smt.c b/drivers/net/ethernet/chelsio/cxgb4/smt.c
index 7b2207a..eaf1fb7 100644 (file)
--- a/drivers/net/ethernet/chelsio/cxgb4/smt.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/smt.c
@@ -47,8 +47,7 @@ struct smt_data *t4_init_smt(void)
 
        smt_size = SMT_SIZE;
 
-       s = kvzalloc(sizeof(*s) + smt_size * sizeof(struct smt_entry),
-                    GFP_KERNEL);
+       s = kvzalloc(struct_size(s, smtab, smt_size), GFP_KERNEL);
        if (!s)
                return NULL;
        s->smt_size = smt_size;