From dadfe1ad137e6fbe251b4a5dc310840cfe414db4 Mon Sep 17 00:00:00 2001
From: Josh Boyer <jwboyer@redhat.com>
Date: Mon, 20 Feb 2012 15:28:39 -0500
Subject: [PATCH] ums_realtek: do not use stack memory for DMA in
__do_config_autodelink
__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>
---
drivers/usb/storage/realtek_cr.c | 8 +++++++-
1 files changed, 7 insertions(+), 1 deletions(-)
diff --git a/drivers/usb/storage/realtek_cr.c b/drivers/usb/storage/realtek_cr.c
index d32f720..eee2a96 100644
--- a/drivers/usb/storage/realtek_cr.c
+++ b/drivers/usb/storage/realtek_cr.c
@@ -507,9 +507,14 @@ static int __do_config_autodelink(struct us_data *us, u8 *data, u16 len)
{
int retval;
u8 cmnd[12] = {0};
+ u8 *buf;
US_DEBUGP("%s, addr = 0xfe47, len = %d\n", __FUNCTION__, len);
+ buf = kmemdup(data, len, GFP_NOIO);
+ if (!buf)
+ return USB_STOR_TRANSPORT_ERROR;
+
cmnd[0] = 0xF0;
cmnd[1] = 0x0E;
cmnd[2] = 0xfe;
@@ -517,7 +522,8 @@ static int __do_config_autodelink(struct us_data *us, u8 *data, u16 len)
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;
}
--
1.7.9