iommufd: viommu: free memory allocated by kvcalloc() using kvfree()

Use kvfree() instead of kfree() to free pages allocated by kvcalloc()
in iommufs_hw_queue_alloc_phys() to fix potential memory corruption.
Ensure the memory is properly freed, as kvcalloc may internally use
vmalloc or kmalloc depending on available memory in the system.

Fixes: 2238ddc ("iommufd/viommu: Add IOMMUFD_CMD_HW_QUEUE_ALLOC ioctl")
Link: https://patch.msgid.link/r/[email protected]
Signed-off-by: Akhilesh Patil <[email protected]>
Reviewed-by: Kevin Tian <[email protected]>
Reviewed-by: Nicolin Chen <[email protected]>
Reviewed-by: Pranjal Shrivastava <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>

Author: Akhilesh Patil

drivers/iommu/iommufd/viommu.c

@@ -339,7 +339,7 @@ iommufd_hw_queue_alloc_phys(struct iommu_hw_queue_alloc *cmd,
 	}
 
 	*base_pa = (page_to_pfn(pages[0]) << PAGE_SHIFT) + offset;
-	kfree(pages);
+	kvfree(pages);
 	return access;
 
 out_unpin:
@@ -349,7 +349,7 @@ iommufd_hw_queue_alloc_phys(struct iommu_hw_queue_alloc *cmd,
 out_destroy:
 	iommufd_access_destroy_internal(viommu->ictx, access);
 out_free:
-	kfree(pages);
+	kvfree(pages);
 	return ERR_PTR(rc);
 }