From b0e14951ee0f6c29abc64b92ec7075a159ede37c Mon Sep 17 00:00:00 2001 From: Jiri Kosina Date: Mon, 12 Oct 2009 11:25:56 +0200 Subject: [PATCH] HID: fix possible deadlock in hidraw_read If the loop in hidraw_read() loops more than once, then we might end up trying to acquire already locked mutex, casuing a deadlock. Reported-by: iceberg Signed-off-by: Jiri Kosina --- drivers/hid/hidraw.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c index 0c6639e..b079a9c 100644 --- a/drivers/hid/hidraw.c +++ b/drivers/hid/hidraw.c @@ -47,10 +47,9 @@ static ssize_t hidraw_read(struct file *file, char __user *buffer, size_t count, char *report; DECLARE_WAITQUEUE(wait, current); - while (ret == 0) { - - mutex_lock(&list->read_mutex); + mutex_lock(&list->read_mutex); + while (ret == 0) { if (list->head == list->tail) { add_wait_queue(&list->hidraw->wait, &wait); set_current_state(TASK_INTERRUPTIBLE); -- 2.7.4