On 02/16/2013 05:00 PM, Jussi Kivilinna wrote:
rtlwifi allocates both setup_packet and data buffer of control message urb, using shared kmalloc in _usbctrl_vendorreq_async_write. Structure used for allocating is: struct { u8 data[254]; struct usb_ctrlrequest dr; }; Because 'struct usb_ctrlrequest' is __packed, setup packet is unaligned and DMA mapping of both 'data' and 'dr' confuses ARM/sunxi, leading to memory corruptions and freezes. Patch changes setup packet to be allocated separately. Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Jussi Kivilinna <jussi.kivilinna@xxxxxxxx>
The only change I would make is to convert the WARN_ON to WARN_ON_ONCE. In case something goes wrong, there is no need to spam the logs.
I am not crazy about the overhead in allocating two different blocks for each output packet, but if it is necessary, then it has to happen.
Larry
--- drivers/net/wireless/rtlwifi/usb.c | 44 +++++++++++++++++++++++------------- 1 file changed, 28 insertions(+), 16 deletions(-) diff --git a/drivers/net/wireless/rtlwifi/usb.c b/drivers/net/wireless/rtlwifi/usb.c index 476eaef..d98fcdb 100644 --- a/drivers/net/wireless/rtlwifi/usb.c +++ b/drivers/net/wireless/rtlwifi/usb.c @@ -42,8 +42,12 @@ static void usbctrl_async_callback(struct urb *urb) { - if (urb) - kfree(urb->context); + if (urb) { + /* free dr */ + kfree(urb->setup_packet); + /* free databuf */ + kfree(urb->transfer_buffer); + } } static int _usbctrl_vendorreq_async_write(struct usb_device *udev, u8 request, @@ -55,39 +59,47 @@ static int _usbctrl_vendorreq_async_write(struct usb_device *udev, u8 request, u8 reqtype; struct usb_ctrlrequest *dr; struct urb *urb; - struct rtl819x_async_write_data { - u8 data[REALTEK_USB_VENQT_MAX_BUF_SIZE]; - struct usb_ctrlrequest dr; - } *buf; + const u16 databuf_maxlen = REALTEK_USB_VENQT_MAX_BUF_SIZE; + u8 *databuf; + + if (WARN_ON(len > databuf_maxlen)) + len = databuf_maxlen; pipe = usb_sndctrlpipe(udev, 0); /* write_out */ reqtype = REALTEK_USB_VENQT_WRITE; - buf = kmalloc(sizeof(*buf), GFP_ATOMIC); - if (!buf) + dr = kmalloc(sizeof(*dr), GFP_ATOMIC); + if (!dr) return -ENOMEM; + databuf = kmalloc(databuf_maxlen, GFP_ATOMIC); + if (!databuf) { + kfree(dr); + return -ENOMEM; + } + urb = usb_alloc_urb(0, GFP_ATOMIC); if (!urb) { - kfree(buf); + kfree(databuf); + kfree(dr); return -ENOMEM; } - dr = &buf->dr; - dr->bRequestType = reqtype; dr->bRequest = request; dr->wValue = cpu_to_le16(value); dr->wIndex = cpu_to_le16(index); dr->wLength = cpu_to_le16(len); /* data are already in little-endian order */ - memcpy(buf, pdata, len); + memcpy(databuf, pdata, len); usb_fill_control_urb(urb, udev, pipe, - (unsigned char *)dr, buf, len, - usbctrl_async_callback, buf); + (unsigned char *)dr, databuf, len, + usbctrl_async_callback, NULL); rc = usb_submit_urb(urb, GFP_ATOMIC); - if (rc < 0) - kfree(buf); + if (rc < 0) { + kfree(databuf); + kfree(dr); + } usb_free_urb(urb); return rc; } -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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