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ath3k: don't use stack memory for DMA

PATCH Superseded Stanislaw Gruszka 2 participants 4 messages Jun 27, 2013 – Jul 9, 2013 Bluetooth drivers

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Stanislaw Gruszka

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#0 lore raw

PATCH 1/1 ath3k: don't use stack memory for DMA

Memory allocated by vmalloc (including stack) can not be used for DMA, i.e. data pointer on usb_control_msg() should not point to stack memory.

Resolves:
https://bugzilla.redhat.com/show_bug.cgi?id=977558

Reported-and-tested-by Andy Lawrence <[email protected]>
Signed-off-by Stanislaw Gruszka <[email protected]>
---
 drivers/bluetooth/ath3k.c | 38 +++++++++++++++++++++++++++++---------
 1 file changed, 29 insertions(+), 9 deletions(-)
drivers/bluetooth/ath3k.c +29 -9
index 11f467c..81b636c 100644
@@ -193,24 +193,44 @@ error:
 
 static int ath3k_get_state(struct usb_device *udev, unsigned char *state)
 {
-	int pipe = 0;
+	int ret, pipe = 0;
+	char *buf;
+
+	buf = kmalloc(1, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
 
 	pipe = usb_rcvctrlpipe(udev, 0);
-	return usb_control_msg(udev, pipe, ATH3K_GETSTATE,
-			USB_TYPE_VENDOR | USB_DIR_IN, 0, 0,
-			state, 0x01, USB_CTRL_SET_TIMEOUT);
+	ret = usb_control_msg(udev, pipe, ATH3K_GETSTATE,
+			      USB_TYPE_VENDOR | USB_DIR_IN, 0, 0,
+			      buf, 1, USB_CTRL_SET_TIMEOUT);
+
+	*state = *buf;
+	kfree(buf);
+
+	return ret;
 }
 
 static int ath3k_get_version(struct usb_device *udev,
 			struct ath3k_version *version)
 {
-	int pipe = 0;
+	int ret, pipe = 0;
+	char *buf;
+	const int size = sizeof(struct ath3k_version);
+	
+	buf = kmalloc(size, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
 
 	pipe = usb_rcvctrlpipe(udev, 0);
-	return usb_control_msg(udev, pipe, ATH3K_GETVERSION,
-			USB_TYPE_VENDOR | USB_DIR_IN, 0, 0, version,
-			sizeof(struct ath3k_version),
-			USB_CTRL_SET_TIMEOUT);
+	ret = usb_control_msg(udev, pipe, ATH3K_GETVERSION,
+			      USB_TYPE_VENDOR | USB_DIR_IN, 0, 0,
+			      buf, size, USB_CTRL_SET_TIMEOUT);
+
+	memcpy(version, buf, size);
+	kfree(buf);
+
+	return ret;
 }
 
 static int ath3k_load_fwfile(struct usb_device *udev,
Signature · 1 line
1.7.11.7
#1 lore raw

Hi Stanislaw,

Quoted 17 lines · Stanislaw Gruszka

Memory allocated by vmalloc (including stack) can not be used for DMA, i.e. data pointer on usb_control_msg() should not point to stack memory.

Resolves:
https://bugzilla.redhat.com/show_bug.cgi?id=977558

Reported-and-tested-by Andy Lawrence <[email protected]>
Signed-off-by Stanislaw Gruszka <[email protected]>
---
 drivers/bluetooth/ath3k.c | 38 +++++++++++++++++++++++++++++---------
 1 file changed, 29 insertions(+), 9 deletions(-)
drivers/bluetooth/ath3k.c +0 -0
index 11f467c..81b636c 100644

drivers/bluetooth/ath3k.c error: · line 199

Quoted 8 lines
drivers/bluetooth/ath3k.c +4 -1
@@ -193,24 +193,44 @@ error:
 
 static int ath3k_get_state(struct usb_device *udev, unsigned char *state)
 {
-	int pipe = 0;
+	int ret, pipe = 0;
+	char *buf;
+
+	buf = kmalloc(1, GFP_KERNEL);

Can we make this:

	buf = kmalloc(sizeof(*buf), GFP_KERNEL);

drivers/bluetooth/ath3k.c error: · line 206

Quoted 10 lines
drivers/bluetooth/ath3k.c +5 -3
+	if (!buf)
+		return -ENOMEM;
 
 	pipe = usb_rcvctrlpipe(udev, 0);
-	return usb_control_msg(udev, pipe, ATH3K_GETSTATE,
-			USB_TYPE_VENDOR | USB_DIR_IN, 0, 0,
-			state, 0x01, USB_CTRL_SET_TIMEOUT);
+	ret = usb_control_msg(udev, pipe, ATH3K_GETSTATE,
+			      USB_TYPE_VENDOR | USB_DIR_IN, 0, 0,
+			      buf, 1, USB_CTRL_SET_TIMEOUT);

sizeof(*buf) instead of "1"

drivers/bluetooth/ath3k.c error: · line 218

Quoted 13 lines
drivers/bluetooth/ath3k.c +7 -1
+
+	*state = *buf;
+	kfree(buf);
+
+	return ret;
 }
 
 static int ath3k_get_version(struct usb_device *udev,
 			struct ath3k_version *version)
 {
-	int pipe = 0;
+	int ret, pipe = 0;
+	char *buf;

this should be struct ath3k_version *buf;

drivers/bluetooth/ath3k.c error: · line 219

Quoted 1 line
drivers/bluetooth/ath3k.c +1 -0
+	const int size = sizeof(struct ath3k_version);

and here sizeof(*buf);

Gustavo

author
#2 lore raw

PATCH v2 1/1 ath3k: don't use stack memory for DMA

Memory allocated by vmalloc (including stack) can not be used for DMA, i.e. data pointer on usb_control_msg() should not point to stack memory.

Resolves:
https://bugzilla.redhat.com/show_bug.cgi?id=977558

Reported-and-tested-by Andy Lawrence <[email protected]>
Signed-off-by Stanislaw Gruszka <[email protected]>
---
 drivers/bluetooth/ath3k.c | 38 +++++++++++++++++++++++++++++---------
 1 file changed, 29 insertions(+), 9 deletions(-)

v1 -> v2 : use sizeof(*buf)

drivers/bluetooth/ath3k.c +29 -9
index 11f467c..5e3a86f 100644
@@ -193,24 +193,44 @@ error:
 
 static int ath3k_get_state(struct usb_device *udev, unsigned char *state)
 {
-	int pipe = 0;
+	int ret, pipe = 0;
+	char *buf;
+
+	buf = kmalloc(sizeof(*buf), GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
 
 	pipe = usb_rcvctrlpipe(udev, 0);
-	return usb_control_msg(udev, pipe, ATH3K_GETSTATE,
-			USB_TYPE_VENDOR | USB_DIR_IN, 0, 0,
-			state, 0x01, USB_CTRL_SET_TIMEOUT);
+	ret = usb_control_msg(udev, pipe, ATH3K_GETSTATE,
+			      USB_TYPE_VENDOR | USB_DIR_IN, 0, 0,
+			      buf, sizeof(*buf), USB_CTRL_SET_TIMEOUT);
+
+	*state = *buf;
+	kfree(buf);
+
+	return ret;
 }
 
 static int ath3k_get_version(struct usb_device *udev,
 			struct ath3k_version *version)
 {
-	int pipe = 0;
+	int ret, pipe = 0;
+	struct ath3k_version *buf;
+	const int size = sizeof(*buf);
+
+	buf = kmalloc(size, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
 
 	pipe = usb_rcvctrlpipe(udev, 0);
-	return usb_control_msg(udev, pipe, ATH3K_GETVERSION,
-			USB_TYPE_VENDOR | USB_DIR_IN, 0, 0, version,
-			sizeof(struct ath3k_version),
-			USB_CTRL_SET_TIMEOUT);
+	ret = usb_control_msg(udev, pipe, ATH3K_GETVERSION,
+			      USB_TYPE_VENDOR | USB_DIR_IN, 0, 0,
+			      buf, size, USB_CTRL_SET_TIMEOUT);
+
+	memcpy(version, buf, size);
+	kfree(buf);
+
+	return ret;
 }
 
 static int ath3k_load_fwfile(struct usb_device *udev,
#3 lore raw

Hi Stanislaw,

Quoted 11 lines · Stanislaw Gruszka

Memory allocated by vmalloc (including stack) can not be used for DMA, i.e. data pointer on usb_control_msg() should not point to stack memory.

Resolves:
https://bugzilla.redhat.com/show_bug.cgi?id=977558

Reported-and-tested-by Andy Lawrence <[email protected]>
Signed-off-by Stanislaw Gruszka <[email protected]>
---
 drivers/bluetooth/ath3k.c | 38 +++++++++++++++++++++++++++++---------
 1 file changed, 29 insertions(+), 9 deletions(-)

Patch has been applied to bluetooth-next. Thanks.

Gustavo