From cb174681a9ececa6702f114b85bdf82144b6a5af Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Tue, 19 Oct 2010 11:29:55 +0200 Subject: HID: hidraw: fix window in hidraw_release There is a window between hidraw_table check and its dereference. In that window, the device may be unplugged and removed form the system and we will then dereference NULL. Lock that place properly so that either we get NULL and jump out or we can work with real pointer. Signed-off-by: Jiri Slaby Signed-off-by: Jiri Kosina --- drivers/hid/hidraw.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c index 47d70c523d93..5a6f99b1db12 100644 --- a/drivers/hid/hidraw.c +++ b/drivers/hid/hidraw.c @@ -212,9 +212,13 @@ static int hidraw_release(struct inode * inode, struct file * file) unsigned int minor = iminor(inode); struct hidraw *dev; struct hidraw_list *list = file->private_data; + int ret; - if (!hidraw_table[minor]) - return -ENODEV; + mutex_lock(&minors_lock); + if (!hidraw_table[minor]) { + ret = -ENODEV; + goto unlock; + } list_del(&list->node); dev = hidraw_table[minor]; @@ -227,10 +231,12 @@ static int hidraw_release(struct inode * inode, struct file * file) kfree(list->hidraw); } } - kfree(list); + ret = 0; +unlock: + mutex_unlock(&minors_lock); - return 0; + return ret; } static long hidraw_ioctl(struct file *file, unsigned int cmd, -- cgit v1.2.2