From 332c1def71fec9b6dfed59c97423d92f741e78f1 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Tue, 19 Oct 2010 11:29:55 +0200 Subject: [PATCH] HID: hidraw: fix window in hidraw_release commit cb174681a9ececa6702f114b85bdf82144b6a5af upstream. [ Backport to .32.y by Antonio Ospite ] 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 Signed-off-by: Antonio Ospite Signed-off-by: Greg Kroah-Hartman Signed-off-by: Willy Tarreau --- drivers/hid/hidraw.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c index 8c030d9dd0dd..b88f6b3235f8 100644 --- a/drivers/hid/hidraw.c +++ b/drivers/hid/hidraw.c @@ -196,11 +196,14 @@ 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; + mutex_lock(&minors_lock); if (!hidraw_table[minor]) { printk(KERN_EMERG "hidraw device with minor %d doesn't exist\n", minor); - return -ENODEV; + ret = -ENODEV; + goto unlock; } list_del(&list->node); @@ -211,10 +214,12 @@ static int hidraw_release(struct inode * inode, struct file * file) else 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, -- 2.39.5