bnx2x: Use struct_size() in kzalloc()
authorGustavo A. R. Silva <gustavo@embeddedor.com>
Fri, 8 Feb 2019 03:29:10 +0000 (21:29 -0600)
committerDavid S. Miller <davem@davemloft.net>
Sat, 9 Feb 2019 06:57:28 +0000 (22:57 -0800)
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[];
};

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

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

instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL)

Notice that, in this case, variable fsz is not necessary, hence
it is removed.

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>
drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c

index 8e0a317..a9bdc21 100644 (file)
@@ -1654,13 +1654,9 @@ static int bnx2x_vf_mbx_macvlan_list(struct bnx2x *bp,
 {
        int i, j;
        struct bnx2x_vf_mac_vlan_filters *fl = NULL;
-       size_t fsz;
 
-       fsz = tlv->n_mac_vlan_filters *
-             sizeof(struct bnx2x_vf_mac_vlan_filter) +
-             sizeof(struct bnx2x_vf_mac_vlan_filters);
-
-       fl = kzalloc(fsz, GFP_KERNEL);
+       fl = kzalloc(struct_size(fl, filters, tlv->n_mac_vlan_filters),
+                    GFP_KERNEL);
        if (!fl)
                return -ENOMEM;