[PATCH] HID: roccat: free buffered reports when destroying device

[raoxu]

From: Xu Rao <raoxu@xxxxxxxxxxxxx>

roccat_report_event() duplicates each report with kmemdup() and stores
the allocation in a circular-buffer slot. The allocation is released only
when that slot is reused.

The device destruction paths free struct roccat_device without releasing
reports still stored in cbuf[]. This makes those allocations unreachable
and leaks up to ROCCAT_CBUF_SIZE report buffers per device.

Add a small destructor that frees every buffered report before freeing the
device, and use it in both paths that can destroy a registered device.

Fixes: 206f5f2fcb5f ("HID: roccat: propagate special events of roccat hardware to userspace")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Xu Rao <raoxu@xxxxxxxxxxxxx>
---
 drivers/hid/hid-roccat.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/hid/hid-roccat.c b/drivers/hid/hid-roccat.c
index d6fff53d4ee7..4f15eb951039 100644
--- a/drivers/hid/hid-roccat.c
+++ b/drivers/hid/hid-roccat.c
@@ -70,6 +70,15 @@ static struct roccat_device *devices[ROCCAT_MAX_DEVICES];
 /* protects modifications of devices array */
 static DEFINE_MUTEX(devices_lock);

+static void roccat_free_device(struct roccat_device *device)
+{
+	int i;
+
+	for (i = 0; i < ROCCAT_CBUF_SIZE; i++)
+		kfree(device->cbuf[i].value);
+	kfree(device);
+}
+
 static ssize_t roccat_read(struct file *file, char __user *buffer,
 		size_t count, loff_t *ppos)
 {
@@ -226,7 +235,7 @@ static int roccat_release(struct inode *inode, struct file *file)
 			hid_hw_power(device->hid, PM_HINT_NORMAL);
 			hid_hw_close(device->hid);
 		} else {
-			kfree(device);
+			roccat_free_device(device);
 		}
 	}

@@ -374,7 +383,7 @@ void roccat_disconnect(int minor)
 		hid_hw_close(device->hid);
 		wake_up_interruptible(&device->wait);
 	} else {
-		kfree(device);
+		roccat_free_device(device);
 	}
 }
 EXPORT_SYMBOL_GPL(roccat_disconnect);
--
2.50.1