From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Korsgaard Subject: Re: [PATCH RESEND] dm9601: don't do usb transfers of data on stack Date: Fri, 11 Jul 2008 14:57:39 +0200 Message-ID: <87mykoefy4.fsf@macbook.be.48ers.dk> References: <87mykoircs.fsf@macbook.be.48ers.dk> <200807111400.38312.oliver@neukum.org> <87vdzcehs9.fsf@macbook.be.48ers.dk> <200807111422.56406.oliver@neukum.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, linux-usb@vger.kernel.org To: Oliver Neukum , jeff@garzik.org Return-path: Received: from wr-out-0506.google.com ([64.233.184.232]:30049 "EHLO wr-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751218AbYGKM5m (ORCPT ); Fri, 11 Jul 2008 08:57:42 -0400 Received: by wr-out-0506.google.com with SMTP id 69so2808384wri.5 for ; Fri, 11 Jul 2008 05:57:41 -0700 (PDT) In-Reply-To: <200807111422.56406.oliver@neukum.org> (Oliver Neukum's message of "Fri\, 11 Jul 2008 14\:22\:55 +0200") Sender: netdev-owner@vger.kernel.org List-ID: dm_{read,write}() were doing USB transfers of data on stack, which isn't allowed. Fix it by kmalloc'ing a temporary buffer. Clean up the error handling for short transfers while we're at it. Signed-off-by: Peter Korsgaard --- drivers/net/usb/dm9601.c | 52 +++++++++++++++++++++++++++++++++++++-------- 1 files changed, 42 insertions(+), 10 deletions(-) diff --git a/drivers/net/usb/dm9601.c b/drivers/net/usb/dm9601.c index f7319d3..78df2be 100644 --- a/drivers/net/usb/dm9601.c +++ b/drivers/net/usb/dm9601.c @@ -55,12 +55,28 @@ static int dm_read(struct usbnet *dev, u8 reg, u16 length, void *data) { + void *buf; + int err = -ENOMEM; + devdbg(dev, "dm_read() reg=0x%02x length=%d", reg, length); - return usb_control_msg(dev->udev, - usb_rcvctrlpipe(dev->udev, 0), - DM_READ_REGS, - USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE, - 0, reg, data, length, USB_CTRL_SET_TIMEOUT); + + buf = kmalloc(length, GFP_KERNEL); + if (!buf) + goto out; + + err = usb_control_msg(dev->udev, + usb_rcvctrlpipe(dev->udev, 0), + DM_READ_REGS, + USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE, + 0, reg, buf, length, USB_CTRL_SET_TIMEOUT); + if (err == length) + memcpy(data, buf, length); + else if (err >= 0) + err = -EINVAL; + kfree(buf); + + out: + return err; } static int dm_read_reg(struct usbnet *dev, u8 reg, u8 *value) @@ -70,12 +86,28 @@ static int dm_read_reg(struct usbnet *dev, u8 reg, u8 *value) static int dm_write(struct usbnet *dev, u8 reg, u16 length, void *data) { + void *buf = NULL; + int err = -ENOMEM; + devdbg(dev, "dm_write() reg=0x%02x, length=%d", reg, length); - return usb_control_msg(dev->udev, - usb_sndctrlpipe(dev->udev, 0), - DM_WRITE_REGS, - USB_DIR_OUT | USB_TYPE_VENDOR |USB_RECIP_DEVICE, - 0, reg, data, length, USB_CTRL_SET_TIMEOUT); + + if (data) { + buf = kmalloc(length, GFP_KERNEL); + if (!buf) + goto out; + memcpy(buf, data, length); + } + + err = usb_control_msg(dev->udev, + usb_sndctrlpipe(dev->udev, 0), + DM_WRITE_REGS, + USB_DIR_OUT | USB_TYPE_VENDOR |USB_RECIP_DEVICE, + 0, reg, buf, length, USB_CTRL_SET_TIMEOUT); + kfree(buf); + if (err >= 0 && err < length) + err = -EINVAL; + out: + return err; } static int dm_write_reg(struct usbnet *dev, u8 reg, u8 value) -- 1.5.6.2 -- Bye, Peter Korsgaard