On Thu, May 11, 2023 at 10:15:53AM +0800, Zhangfei Gao wrote:
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->filep->f_mapping to replace uacce->inode->i_mapping.
Signed-off-by: Weili Qian qianweili@huawei.com Signed-off-by: Zhangfei Gao zhangfei.gao@linaro.org
drivers/misc/uacce/uacce.c | 16 +++++++++------- include/linux/uacce.h | 4 ++-- 2 files changed, 11 insertions(+), 9 deletions(-)
diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c index 346bd7cf2e94..740ace422baa 100644 --- a/drivers/misc/uacce/uacce.c +++ b/drivers/misc/uacce/uacce.c @@ -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->private_data = filep; 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 @@ -589,6 +583,8 @@ void uacce_remove(struct uacce_device *uacce) mutex_lock(&uacce->mutex); /* ensure no open queue remains */ list_for_each_entry_safe(q, next_q, &uacce->queues, list) {
struct file *filep = q->private_data;
- /*
- Taking q->mutex ensures that fops do not use the defunct
- uacce->ops after the queue is disabled.
@@ -597,6 +593,12 @@ 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(filep->f_mapping, 0, 0, 1);
/* disable sva now since no opened queues */ diff --git a/include/linux/uacce.h b/include/linux/uacce.h index 0a81c3dfd26c..64b800b74436 100644 --- a/include/linux/uacce.h +++ b/include/linux/uacce.h @@ -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()
*/
- @private_data: private data for saving filep
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;
- void *private_data;
Make this a real pointer to the inode, no need to make this "void *", right?
thanks,
greg k-h