diff options
| author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2019-02-18 13:06:41 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-02-19 14:41:38 +0100 |
| commit | 5ebf5c890324ffa5eaca579dac6913f3e29a28e3 (patch) | |
| tree | db6492855529ce765dee22f752bf2dd3f3c51ea5 | |
| parent | eeca7606dd6e2445f505903f235e908eb7b78dfc (diff) | |
usb: core: config: Use struct_size() in kzalloc()
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 len 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/core/config.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c index 7bb6b1bd06c8..20ff036b4c22 100644 --- a/drivers/usb/core/config.c +++ b/drivers/usb/core/config.c @@ -552,7 +552,7 @@ static int usb_parse_configuration(struct usb_device *dev, int cfgidx, unsigned char *buffer2; int size2; struct usb_descriptor_header *header; - int len, retval; + int retval; u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES]; unsigned iad_num = 0; @@ -707,8 +707,8 @@ static int usb_parse_configuration(struct usb_device *dev, int cfgidx, nalts[i] = j = USB_MAXALTSETTING; } - len = sizeof(*intfc) + sizeof(struct usb_host_interface) * j; - config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL); + intfc = kzalloc(struct_size(intfc, altsetting, j), GFP_KERNEL); + config->intf_cache[i] = intfc; if (!intfc) return -ENOMEM; kref_init(&intfc->ref); |