Re: [PATCH] iommu/amd: Check if domain is NULL before dereference it

From: Dan Carpenter
Date: Thu Aug 24 2017 - 08:32:56 EST


Take a look at this code for example. But all the places which call
get_domain() are the same:

drivers/iommu/amd_iommu.c
2648 page = virt_to_page(virt_addr);
2649 size = PAGE_ALIGN(size);
2650
2651 domain = get_domain(dev);
^^^^^^^^^^^^^^
imagined get_domain() returns NULL.

2652 if (IS_ERR(domain))
2653 goto free_mem;
2654
2655 dma_dom = to_dma_ops_domain(domain);
^^^^^^^^^^^^^^^^^^^^^^^^^
This will Oops.

2656

regards,
dan carpenter