[PATCH 4.4 39/45] catc: Use heap buffer for memory size test

Greg Kroah-Hartman
2017-04-19T15:00:25Z

From: Ben Hutchings <ben@decadent.org.uk>

commit 2d6a0e9de03ee658a9adc3bfb2f0ca55dff1e478 upstream.

Allocating USB buffers on the stack is not portable, and no longer
works on x86_64 (with VMAP_STACK enabled as per default).

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Brad Spengler <spender@grsecurity.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/net/usb/catc.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)

--- a/drivers/net/usb/catc.c
+++ b/drivers/net/usb/catc.c
@@ -777,7 +777,7 @@ static int catc_probe(struct usb_interfa
struct net_device *netdev;
struct catc *catc;
u8 broadcast[ETH_ALEN];
- int i, pktsz, ret;
+ int pktsz, ret;

if (usb_set_interface(usbdev,
intf->altsetting->desc.bInterfaceNumber, 1)) {
@@ -841,15 +841,24 @@ static int catc_probe(struct usb_interfa
catc->irq_buf, 2, catc_irq_done, catc, 1);

if (!catc->is_f5u011) {
+ u32 *buf;
+ int i;
+
dev_dbg(dev, "Checking memory size\n");

- i = 0x12345678;
- catc_write_mem(catc, 0x7a80, &i, 4);
- i = 0x87654321;
- catc_write_mem(catc, 0xfa80, &i, 4);
- catc_read_mem(catc, 0x7a80, &i, 4);
+ buf = kmalloc(4, GFP_KERNEL);
+ if (!buf) {
+ ret = -ENOMEM;
+ goto fail_free;
+ }
+
+ *buf = 0x12345678;
+ catc_write_mem(catc, 0x7a80, buf, 4);
+ *buf = 0x87654321;
+ catc_write_mem(catc, 0xfa80, buf, 4);
+ catc_read_mem(catc, 0x7a80, buf, 4);

- switch (i) {
+ switch (*buf) {
case 0x12345678:
catc_set_reg(catc, TxBufCount, 8);
catc_set_reg(catc, RxBufCount, 32);
@@ -864,6 +873,8 @@ static int catc_probe(struct usb_interfa
dev_dbg(dev, "32k Memory\n");
break;
}
+
+ kfree(buf);

dev_dbg(dev, "Getting MAC from SEEROM.\n");