| Message ID | 20190107173953.GA6154@embeddedor (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | 02fc1848414e116b948ebd70e865b7539e5d7b8d |
| Delegated to: | Jason Gunthorpe |
| Headers | show |
| Series | IB/usnic: Use struct_size() in kmalloc() | expand |
On Mon, Jan 07, 2019 at 11:39:54AM -0600, Gustavo A. R. Silva wrote: > 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 = kmalloc(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 = kmalloc(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/infiniband/hw/usnic/usnic_uiom.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) Applied to for-next, thanks Jason
diff --git a/drivers/infiniband/hw/usnic/usnic_uiom.c b/drivers/infiniband/hw/usnic/usnic_uiom.c index 49275a548751..ce01a59fccc4 100644 --- a/drivers/infiniband/hw/usnic/usnic_uiom.c +++ b/drivers/infiniband/hw/usnic/usnic_uiom.c @@ -157,9 +157,8 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable, off = 0; while (ret) { - chunk = kmalloc(sizeof(*chunk) + - sizeof(struct scatterlist) * - min_t(int, ret, USNIC_UIOM_PAGE_CHUNK), + chunk = kmalloc(struct_size(chunk, page_list, + min_t(int, ret, USNIC_UIOM_PAGE_CHUNK)), GFP_KERNEL); if (!chunk) { ret = -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 = kmalloc(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 = kmalloc(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/infiniband/hw/usnic/usnic_uiom.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)