| Message ID | 20190108154046.GA13254@embeddedor (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | da79ff6e586bd5aaa3bd9c73e56ae9d9183c3263 |
| Headers | show |
| Series | xhci: Use struct_size() in kzalloc() | expand |
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 005e65922608..7fa58c99f126 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -1455,8 +1455,7 @@ static int xhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flag else num_tds = 1; - urb_priv = kzalloc(sizeof(struct urb_priv) + - num_tds * sizeof(struct xhci_td), mem_flags); + urb_priv = kzalloc(struct_size(urb_priv, td, num_tds), mem_flags); if (!urb_priv) return -ENOMEM;
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; void *entry[]; }; instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, 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); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> --- drivers/usb/host/xhci.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)