usb: iowarrior: don't trust report_size for buffer size

If the iowarrior devices in this case statement support more than 8 bytes
per report, it is possible to write past the end of a kernel heap allocation.
This will probably never be possible, but change the allocation to be more
defensive anyway.

Signed-off-by: Kees Cook <kees.cook@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/usb/misc/iowarrior.c b/drivers/usb/misc/iowarrior.c
index bc88c79875a1..8ed8d05750d4 100644
--- a/drivers/usb/misc/iowarrior.c
+++ b/drivers/usb/misc/iowarrior.c
@@ -374,7 +374,7 @@ static ssize_t iowarrior_write(struct file *file,
         case USB_DEVICE_ID_CODEMERCS_IOWPV2:
         case USB_DEVICE_ID_CODEMERCS_IOW40:
                 /* IOW24 and IOW40 use a synchronous call */
-                buf = kmalloc(8, GFP_KERNEL);   /* 8 bytes are enough for both products */
+                buf = kmalloc(count, GFP_KERNEL);
                 if (!buf) {
                         retval = -ENOMEM;
                         goto exit;