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>
This commit is contained in:
Kees Cook 2010-10-11 11:28:16 -07:00 committed by Greg Kroah-Hartman
parent cfb8da8f69
commit 3ed780117d

View File

@ -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;