On 12/5/25 2:46 PM, Jason Gunthorpe wrote:
On Fri, Dec 05, 2025 at 10:40:49AM +0800, Lai, Yi wrote:
Hi Alejandro Jimenez,
Greetings!
I used Syzkaller and found that there is WARNING in iommufd_fops_release in
linux-next next-20251203.
After bisection and the first bad commit is:
"
789a5913b29c iommu/amd: Use the generic iommu page table
"
This bisect didn't work out, it is close, but the commit is
Thank you Jason for debugging this. I was wondering what could be the
possible relation with the AMD changes, since the commit doesn't touch
iommufd/main.c, and the syskaller logs show Intel HW so the AMD driver
code is not involved.
Thank you,
Alejandro
e93d5945ed5b ("iommufd: Change the selftest to use iommupt instead of xarray")
It is a refcount leak:
@@ -1215,8 +1215,10 @@ static int iommufd_test_md_check_pa(struct iommufd_ucmd
*ucmd,
page_size = 1 << __ffs(mock->domain.pgsize_bitmap);
if (iova % page_size || length % page_size ||
(uintptr_t)uptr % page_size ||
- check_add_overflow((uintptr_t)uptr, (uintptr_t)length, &end))
- return -EINVAL;
+ check_add_overflow((uintptr_t)uptr, (uintptr_t)length, &end)) {
+ rc = -EINVAL;
+ goto out_put;
+ }
I'll send a patch, thanks
Jason
