linux-stable/include
Fenghua Yu 0ec8ce0739 dmaengine: idxd: Do not enable user type Work Queue without Shared Virtual Addressing
When the idxd_user_drv driver is bound to a Work Queue (WQ) device
without IOMMU or with IOMMU Passthrough without Shared Virtual
Addressing (SVA), the application gains direct access to physical
memory via the device by programming physical address to a submitted
descriptor. This allows direct userspace read and write access to
arbitrary physical memory. This is inconsistent with the security
goals of a good kernel API.

Unlike vfio_pci driver, the IDXD char device driver does not provide any
ways to pin user pages and translate the address from user VA to IOVA or
PA without IOMMU SVA. Therefore the application has no way to instruct the
device to perform DMA function. This makes the char device not usable for
normal application usage.

Since user type WQ without SVA cannot be used for normal application usage
and presents the security issue, bind idxd_user_drv driver and enable user
type WQ only when SVA is enabled (i.e. user PASID is enabled).

Fixes: 448c3de8ac ("dmaengine: idxd: create user driver for wq 'device'")
Cc: stable@vger.kernel.org
Suggested-by: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Link: https://lore.kernel.org/r/20221014222541.3912195-1-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-10-19 19:02:10 +05:30
..
acpi platform-drivers-x86 for v6.1-1 2022-10-05 10:38:24 -07:00
asm-generic - hfs and hfsplus kmap API modernization from Fabio Francesco 2022-10-12 11:00:22 -07:00
clocksource
crypto
drm Driver core changes for 6.1-rc1 2022-10-07 17:04:10 -07:00
dt-bindings These are the pin control changes for the v6.1 kernel cycle: 2022-10-11 10:59:59 -07:00
keys
kunit kunit: declare kunit_assert structs as const 2022-10-07 10:19:18 -06:00
kvm
linux Random number generator fixes for Linux 6.1-rc1. 2022-10-16 15:27:07 -07:00
math-emu
media USB/Thunderbolt changes for 6.1-rc1 2022-10-07 16:48:26 -07:00
memory
misc
net Random number generator fixes for Linux 6.1-rc1. 2022-10-16 15:27:07 -07:00
pcmcia
ras
rdma
rv
scsi SCSI misc on 20221007 2022-10-07 12:33:18 -07:00
soc RISC-V Patches for the 6.1 Merge Window, Part 2 2022-10-14 11:21:11 -07:00
sound ALSA: hda: Update register polling macros 2022-10-09 12:34:32 +02:00
target
trace f2fs-for-6.1-rc1 2022-10-10 20:28:41 -07:00
uapi dmaengine: idxd: Do not enable user type Work Queue without Shared Virtual Addressing 2022-10-19 19:02:10 +05:30
ufs SCSI misc on 20221007 2022-10-07 12:33:18 -07:00
vdso
video
xen xen/virtio: enable grant based virtio on x86 2022-10-10 14:31:26 +02:00