| From 4898e07174b79013afd2b422ef6c4336ef8e6783 Mon Sep 17 00:00:00 2001 |
| From: "jwboyer@redhat.com" <jwboyer@redhat.com> |
| Date: Mon, 20 Feb 2012 15:34:34 -0500 |
| Subject: USB: ums_realtek: do not use stack memory for DMA in __do_config_autodelink |
| |
| From: Josh Boyer <jwboyer@redhat.com> |
| |
| commit 4898e07174b79013afd2b422ef6c4336ef8e6783 upstream. |
| |
| __do_config_autodelink passes the data variable to the transport function. |
| If the calling functions pass a stack variable, this will eventually trigger |
| a DMA-API debug backtrace for mapping stack memory in the DMA buffer. Fix |
| this by calling kmemdup for the passed data instead. |
| |
| Signed-off-by: Josh Boyer <jwboyer@redhat.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/usb/storage/realtek_cr.c | 8 +++++++- |
| 1 file changed, 7 insertions(+), 1 deletion(-) |
| |
| --- a/drivers/usb/storage/realtek_cr.c |
| +++ b/drivers/usb/storage/realtek_cr.c |
| @@ -509,9 +509,14 @@ static int __do_config_autodelink(struct |
| int retval; |
| u16 addr = 0xFE47; |
| u8 cmnd[12] = {0}; |
| + u8 *buf; |
| |
| US_DEBUGP("%s, addr = 0x%x, len = %d\n", __FUNCTION__, addr, len); |
| |
| + buf = kmemdup(data, len, GFP_NOIO); |
| + if (!buf) |
| + return USB_STOR_TRANSPORT_ERROR; |
| + |
| cmnd[0] = 0xF0; |
| cmnd[1] = 0x0E; |
| cmnd[2] = (u8)(addr >> 8); |
| @@ -519,7 +524,8 @@ static int __do_config_autodelink(struct |
| cmnd[4] = (u8)(len >> 8); |
| cmnd[5] = (u8)len; |
| |
| - retval = rts51x_bulk_transport_special(us, 0, cmnd, 12, data, len, DMA_TO_DEVICE, NULL); |
| + retval = rts51x_bulk_transport_special(us, 0, cmnd, 12, buf, len, DMA_TO_DEVICE, NULL); |
| + kfree(buf); |
| if (retval != USB_STOR_TRANSPORT_GOOD) { |
| return -EIO; |
| } |
