usb: iowarrior: replace kmalloc with kmalloc_array

On 8/23/18 12:43 PM, Kees Cook wrote:

On Thu, Aug 23, 2018 at 10:31 AM, Gustavo A. R. Silva
[off-list ref] wrote:

quoted

A common flaw in the kernel is integer overflow during memory allocation
size calculations. In an effort to reduce the frequency of these bugs,
kmalloc_array was implemented, which allocates memory for an array,
while at the same time detects integer overflow.

This patch replaces cases of:

kmalloc(a * b, gfp)

with:
        kmalloc_array(a * b, gfp)

nit: this should be "kmalloc_array(a, b, gfp)" (This was a typo from
my treewide commit message... :P)

Oops... OK. V3 is on the way. :P

quoted

Signed-off-by: Gustavo A. R. Silva <redacted>
---
 drivers/usb/misc/iowarrior.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/misc/iowarrior.c b/drivers/usb/misc/iowarrior.c
index c2991b8..7a22400 100644
--- a/drivers/usb/misc/iowarrior.c
+++ b/drivers/usb/misc/iowarrior.c

@@ -808,7 +808,7 @@ static int iowarrior_probe(struct usb_interface *interface,
                         dev->int_in_endpoint->bInterval);
        /* create an internal buffer for interrupt data from the device */
        dev->read_queue =
-           kmalloc(((dev->report_size + 1) * MAX_INTERRUPT_BUFFER),
+           kmalloc_array(dev->report_size + 1, MAX_INTERRUPT_BUFFER,
                    GFP_KERNEL);

For this patch with the commit log updated:

Reviewed-by: Kees Cook <redacted>

Thanks!
---
Gustavo