[PATCH v2 13/24] iommu/tegra: gart: use vmalloc_array and vcalloc

[Julia Lawall <Julia.Lawall@xxxxxxxx>]

Use vmalloc_array and vcalloc to protect against
multiplication overflows.

The changes were done using the following Coccinelle
semantic patch:

// <smpl>
@initialize:ocaml@
@@

let rename alloc =
  match alloc with
    "vmalloc" -> "vmalloc_array"
  | "vzalloc" -> "vcalloc"
  | _ -> failwith "unknown"

@@
    size_t e1,e2;
    constant C1, C2;
    expression E1, E2, COUNT, x1, x2, x3;
    typedef u8;
    typedef __u8;
    type t = {u8,__u8,char,unsigned char};
    identifier alloc = {vmalloc,vzalloc};
    fresh identifier realloc = script:ocaml(alloc) { rename alloc };
@@

(
      alloc(x1*x2*x3)
|
      alloc(C1 * C2)
|
      alloc((sizeof(t)) * (COUNT), ...)
|
-     alloc((e1) * (e2))
+     realloc(e1, e2)
|
-     alloc((e1) * (COUNT))
+     realloc(COUNT, e1)
|
-     alloc((E1) * (E2))
+     realloc(E1, E2)
)
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxxx>

---
v2: Use vmalloc_array and vcalloc instead of array_size.
This also leaves a multiplication of a constant by a sizeof
as is.  Two patches are thus dropped from the series.

 drivers/iommu/tegra-gart.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff -u -p a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
--- a/drivers/iommu/tegra-gart.c
+++ b/drivers/iommu/tegra-gart.c
@@ -348,8 +348,8 @@ struct gart_device *tegra_gart_probe(str
 	if (err)
 		goto remove_sysfs;
 
-	gart->savedata = vmalloc(resource_size(res) / GART_PAGE_SIZE *
-				 sizeof(u32));
+	gart->savedata = vmalloc_array(resource_size(res) / GART_PAGE_SIZE,
+				       sizeof(u32));
 	if (!gart->savedata) {
 		err = -ENOMEM;
 		goto unregister_iommu;