Commit df1b056d authored by Zhangfei Gao's avatar Zhangfei Gao Committed by Greg Kroah-Hartman
Browse files

uacce: use q->mapping to replace inode->i_mapping 



The inode can be different in a container, for example, a docker and host
both open the same uacce parent device, which uses the same uacce struct
but different inode, so uacce->inode is not enough.

What's worse, when docker stops, the inode will be destroyed as well,
causing use-after-free in uacce_remove.

So use q->mapping to replace uacce->inode->i_mapping.

Signed-off-by: default avatarWeili Qian <qianweili@huawei.com>
Signed-off-by: default avatarZhangfei Gao <zhangfei.gao@linaro.org>
Link: https://lore.kernel.org/r/20230511095921.9331-2-zhangfei.gao@linaro.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 24ee010b

drivers/misc/uacce/uacce.c

+7 −7
Original line number Diff line number Diff line
@@ -166,8 +166,8 @@ static int uacce_fops_open(struct inode *inode, struct file *filep) 


	init_waitqueue_head(&q->wait);

	filep->private_data = q;

	uacce->inode = inode;

	q->state = UACCE_Q_INIT;

	q->mapping = filep->f_mapping;

	mutex_init(&q->mutex);

	list_add(&q->list, &uacce->queues);

	mutex_unlock(&uacce->mutex);
@@ -574,12 +574,6 @@ void uacce_remove(struct uacce_device *uacce) 


	if (!uacce)

		return;

	/*

	 * unmap remaining mapping from user space, preventing user still

	 * access the mmaped area while parent device is already removed

	 */

	if (uacce->inode)

		unmap_mapping_range(uacce->inode->i_mapping, 0, 0, 1);



	/*

	 * uacce_fops_open() may be running concurrently, even after we remove
@@ -597,6 +591,12 @@ void uacce_remove(struct uacce_device *uacce) 
		uacce_put_queue(q);

		mutex_unlock(&q->mutex);

		uacce_unbind_queue(q);



		/*

		 * unmap remaining mapping from user space, preventing user still

		 * access the mmaped area while parent device is already removed

		 */

		unmap_mapping_range(q->mapping, 0, 0, 1);

	}



	/* disable sva now since no opened queues */

include/linux/uacce.h

+2 −2
Original line number Diff line number Diff line
@@ -86,6 +86,7 @@ enum uacce_q_state { 
 * @state: queue state machine

 * @pasid: pasid associated to the mm

 * @handle: iommu_sva handle returned by iommu_sva_bind_device()

 * @mapping: user space mapping of the queue

 */

struct uacce_queue {

	struct uacce_device *uacce;
@@ -97,6 +98,7 @@ struct uacce_queue { 
	enum uacce_q_state state;

	u32 pasid;

	struct iommu_sva *handle;

	struct address_space *mapping;

};



/**
@@ -114,7 +116,6 @@ struct uacce_queue { 
 * @mutex: protects uacce operation

 * @priv: private pointer of the uacce

 * @queues: list of queues

 * @inode: core vfs

 */

struct uacce_device {

	const char *algs;
@@ -130,7 +131,6 @@ struct uacce_device { 
	struct mutex mutex;

	void *priv;

	struct list_head queues;

	struct inode *inode;

};



#if IS_ENABLED(CONFIG_UACCE)