[RFC PATCH 00/12] hw: Forbid DMA write accesses to MMIO regions

[Philippe Mathieu-Daudé]

Hi,

I'm not suppose to work on this but I couldn't sleep so kept
wondering about this problem the whole night and eventually
woke up to write this quickly, so comments are scarce, sorry.

The first part is obvious anyway, simply pass MemTxAttrs argument.

The main patch is:
"exec/memattrs: Introduce MemTxAttrs::direct_access field".
This way we can restrict accesses to ROM/RAM by setting the
'direct_access' field. Illegal accesses return MEMTX_BUS_ERROR.

Next patch restrict PCI DMA accesses by setting the direct_access
field.

Finally we add an assertion for any DMA write access to indirect
memory to kill a class of bug recently found by Alexander while
fuzzing.

Regards,

Phil.

Klaus Jensen (1):
  pci: pass along the return value of dma_memory_rw

Philippe Mathieu-Daudé (11):
  dma: Let dma_memory_valid() take MemTxAttrs argument
  dma: Let dma_memory_set() take MemTxAttrs argument
  dma: Let dma_memory_rw_relaxed() take MemTxAttrs argument
  dma: Let dma_memory_rw() take MemTxAttrs argument
  dma: Let dma_memory_read/write() take MemTxAttrs argument
  dma: Let dma_memory_map() take MemTxAttrs argument
  docs/devel/loads-stores: Add regexp for DMA functions
  dma: Let load/store DMA functions take MemTxAttrs argument
  exec/memattrs: Introduce MemTxAttrs::direct_access field
  hw/pci: Only allow PCI slave devices to write to direct memory
  dma: Assert when device writes to indirect memory (such MMIO regions)

 docs/devel/loads-stores.rst   |  2 ++
 include/exec/memattrs.h       |  3 ++
 include/hw/pci/pci.h          | 21 ++++++++++---
 include/hw/ppc/spapr_vio.h    | 26 +++++++++------
 include/sysemu/dma.h          | 59 +++++++++++++++++++++--------------
 dma-helpers.c                 | 12 ++++---
 exec.c                        |  8 +++++
 hw/arm/musicpal.c             | 13 ++++----
 hw/arm/smmu-common.c          |  3 +-
 hw/arm/smmuv3.c               | 14 ++++++---
 hw/core/generic-loader.c      |  3 +-
 hw/display/virtio-gpu.c       |  8 +++--
 hw/dma/pl330.c                | 12 ++++---
 hw/dma/sparc32_dma.c          | 16 ++++++----
 hw/dma/xlnx-zynq-devcfg.c     |  6 ++--
 hw/dma/xlnx_dpdma.c           | 10 +++---
 hw/hyperv/vmbus.c             |  8 +++--
 hw/i386/amd_iommu.c           | 16 +++++-----
 hw/i386/intel_iommu.c         | 28 ++++++++++-------
 hw/ide/ahci.c                 |  9 ++++--
 hw/ide/macio.c                |  2 +-
 hw/intc/pnv_xive.c            |  7 +++--
 hw/intc/spapr_xive.c          |  3 +-
 hw/intc/xive.c                |  7 +++--
 hw/misc/bcm2835_property.c    |  3 +-
 hw/misc/macio/mac_dbdma.c     | 10 +++---
 hw/net/allwinner-sun8i-emac.c | 21 ++++++++-----
 hw/net/ftgmac100.c            | 25 +++++++++------
 hw/net/imx_fec.c              | 32 ++++++++++++-------
 hw/nvram/fw_cfg.c             | 16 ++++++----
 hw/pci-host/pnv_phb3.c        |  5 +--
 hw/pci-host/pnv_phb3_msi.c    |  9 ++++--
 hw/pci-host/pnv_phb4.c        |  7 +++--
 hw/sd/allwinner-sdhost.c      | 14 +++++----
 hw/sd/sdhci.c                 | 35 +++++++++++++--------
 hw/usb/hcd-dwc2.c             |  8 ++---
 hw/usb/hcd-ehci.c             |  6 ++--
 hw/usb/hcd-ohci.c             | 28 ++++++++++-------
 hw/usb/libhw.c                |  3 +-
 hw/virtio/virtio.c            |  6 ++--
 trace-events                  |  1 +
 41 files changed, 334 insertions(+), 191 deletions(-)

-- 
2.26.2