HID: debug: fix error handling in hid_debug_events_read()

In the unlikely case of hdev vanishing while hid_debug_events_read() was
sleeping, we can't really break out of the case switch as with other cases,
as on the way out we'll try to remove ourselves from the hdev waitqueue.

Fix this by taking a shortcut exit path and avoiding cleanup that doesn't
make sense in case hdev doesn't exist any more anyway.

Reported-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c
index 8bf61d295ffd..f5021fb3b674 100644
--- a/drivers/hid/hid-debug.c
+++ b/drivers/hid/hid-debug.c
@@ -1127,7 +1127,8 @@ static ssize_t hid_debug_events_read(struct file *file, char __user *buffer,
 
                                 if (!list->hdev || !list->hdev->debug) {
                                         ret = -EIO;
-                                        break;
+                                        set_current_state(TASK_RUNNING);
+                                        goto out;
                                 }
 
                                 /* allow O_NONBLOCK from other threads */