From: Kees Cook <kees.cook@canonical.com>
Date: Mon, 11 Oct 2010 18:28:16 +0000 (-0700)
Subject: usb: iowarrior: don't trust report_size for buffer size
X-Git-Tag: v2.6.34.10~103
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=4c4e53dde50aaebcbe02c8ae0a7bb8ddbbe0ff0d;p=karo-tx-linux.git

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

commit 3ed780117dbe5acb64280d218f0347f238dafed0 upstream.

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>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---

diff --git a/drivers/usb/misc/iowarrior.c b/drivers/usb/misc/iowarrior.c
index 7c8432146d18..f2a4ad59728c 100644
--- a/drivers/usb/misc/iowarrior.c
+++ b/drivers/usb/misc/iowarrior.c
@@ -373,7 +373,7 @@ 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;