CVE-2017-5547 (published 2017-02-06T06:59Z)

drivers/hid/hid-corsair.c in the Linux kernel 4.9.x before 4.9.6 interacts incorrectly with the CONFIG_VMAP_STACK option, which allows local users to cause a denial of service (system crash or memory corruption) or possibly have unspecified other impact by leveraging use of more than one virtual page for a DMA scatterlist.

Severity: HIGH
CVSS v2 base score: 7.2 (AV:L/AC:L/Au:N/C:C/I:C/A:C)
CVSS v3 base score: 7.8, HIGH (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)

Weakness information:
cwe_id: CWE-119
cwe_name: Improper Restriction of Operations within the Bounds of a Memory Buffer
description: The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
extended_description: 
            Certain languages allow direct addressing of memory locations and do not automatically ensure that these locations are valid for the memory buffer that is being referenced. This can cause read or write operations to be performed on memory locations that may be associated with other variables, data structures, or internal program data.
         
         

Fix information:
repo_url: https://github.com/torvalds/linux
commit_details: repo_url: https://github.com/torvalds/linux
author: Johan Hovold
author_date: 2017-01-12 18:17:42+01:00
msg: HID: corsair: fix DMA buffers on stack

Not all platforms support DMA to the stack, and specifically since v4.9
this is no longer supported on x86 with VMAP_STACK either.

Note that the macro-mode buffer was larger than necessary.

Fixes: 6f78193ee9ea ("HID: corsair: Add Corsair Vengeance K90 driver")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
repository: repo_url: https://github.com/torvalds/linux
repo_name: torvalds/linux
description: Linux kernel source tree
repo_language: C
owner: torvalds
file_changes: filename: hid-corsair.c
change_type: ModificationType.MODIFY
diff: @@ -148,7 +148,11 @@ static enum led_brightness k90_backlight_get(struct led_classdev *led_cdev)
 	struct usb_interface *usbif = to_usb_interface(dev->parent);
 	struct usb_device *usbdev = interface_to_usbdev(usbif);
 	int brightness;
-	char data[8];
+	char *data;
+
+	data = kmalloc(8, GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
 
 	ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0),
 			      K90_REQUEST_STATUS,
@@ -158,16 +162,22 @@ static enum led_brightness k90_backlight_get(struct led_classdev *led_cdev)
 	if (ret < 0) {
 		dev_warn(dev, "Failed to get K90 initial state (error %d).\n",
 			 ret);
-		return -EIO;
+		ret = -EIO;
+		goto out;
 	}
 	brightness = data[4];
 	if (brightness < 0 || brightness > 3) {
 		dev_warn(dev,
 			 "Read invalid backlight brightness: %02hhx.\n",
 			 data[4]);
-		return -EIO;
+		ret = -EIO;
+		goto out;
 	}
-	return brightness;
+	ret = brightness;
+out:
+	kfree(data);
+
+	return ret;
 }
 
 static enum led_brightness k90_record_led_get(struct led_classdev *led_cdev)
@@ -253,7 +263,11 @@ static ssize_t k90_show_macro_mode(struct device *dev,
 	struct usb_interface *usbif = to_usb_interface(dev->parent);
 	struct usb_device *usbdev = interface_to_usbdev(usbif);
 	const char *macro_mode;
-	char data[8];
+	char *data;
+
+	data = kmalloc(2, GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
 
 	ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0),
 			      K90_REQUEST_GET_MODE,
@@ -263,7 +277,8 @@ static ssize_t k90_show_macro_mode(struct device *dev,
 	if (ret < 0) {
 		dev_warn(dev, "Failed to get K90 initial mode (error %d).\n",
 			 ret);
-		return -EIO;
+		ret = -EIO;
+		goto out;
 	}
 
 	switch (data[0]) {
@@ -277,10 +292,15 @@ static ssize_t k90_show_macro_mode(struct device *dev,
 	default:
 		dev_warn(dev, "K90 in unknown mode: %02hhx.\n",
 			 data[0]);
-		return -EIO;
+		ret = -EIO;
+		goto out;
 	}
 
-	return snprintf(buf, PAGE_SIZE, "%s\n", macro_mode);
+	ret = snprintf(buf, PAGE_SIZE, "%s\n", macro_mode);
+out:
+	kfree(data);
+
+	return ret;
 }
 
 static ssize_t k90_store_macro_mode(struct device *dev,
@@ -320,7 +340,11 @@ static ssize_t k90_show_current_profile(struct device *dev,
 	struct usb_interface *usbif = to_usb_interface(dev->parent);
 	struct usb_device *usbdev = interface_to_usbdev(usbif);
 	int current_profile;
-	char data[8];
+	char *data;
+
+	data = kmalloc(8, GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
 
 	ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0),
 			      K90_REQUEST_STATUS,
@@ -330,16 +354,22 @@ static ssize_t k90_show_current_profile(struct device *dev,
 	if (ret < 0) {
 		dev_warn(dev, "Failed to get K90 initial state (error %d).\n",
 			 ret);
-		return -EIO;
+		ret = -EIO;
+		goto out;
 	}
 	current_profile = data[7];
 	if (current_profile < 1 || current_profile > 3) {
 		dev_warn(dev, "Read invalid current profile: %02hhx.\n",
 			 data[7]);
-		return -EIO;
+		ret = -EIO;
+		goto out;
 	}
 
-	return snprintf(buf, PAGE_SIZE, "%d\n", current_profile);
+	ret = snprintf(buf, PAGE_SIZE, "%d\n", current_profile);
+out:
+	kfree(data);
+
+	return ret;
 }
 
 static ssize_t k90_store_current_profile(struct device *dev,

programming_language: C