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* [PATCH v10 00/12] Restricted DMA
@ 2021-06-15 13:26 ` Claire Chang
  0 siblings, 0 replies; 124+ messages in thread
From: Claire Chang @ 2021-06-15 13:26 UTC (permalink / raw)
  To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
	Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
	Christoph Hellwig, Marek Szyprowski
  Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
	Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
	bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
	heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
	Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
	xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
	bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
	jani.nikula, jxgao, joonas.lahtinen, linux-pci,
	maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom

This series implements mitigations for lack of DMA access control on
systems without an IOMMU, which could result in the DMA accessing the
system memory at unexpected times and/or unexpected addresses, possibly
leading to data leakage or corruption.

For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is
not behind an IOMMU. As PCI-e, by design, gives the device full access to
system memory, a vulnerability in the Wi-Fi firmware could easily escalate
to a full system exploit (remote wifi exploits: [1a], [1b] that shows a
full chain of exploits; [2], [3]).

To mitigate the security concerns, we introduce restricted DMA. Restricted
DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a
specially allocated region and does memory allocation from the same region.
The feature on its own provides a basic level of protection against the DMA
overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system needs
to provide a way to restrict the DMA to a predefined memory region (this is
usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]).

[1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html
[1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html
[2] https://blade.tencent.com/en/advisories/qualpwn/
[3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/
[4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132

v10:
Address the comments in v9 to
  - fix the dev->dma_io_tlb_mem assignment
  - propagate swiotlb_force setting into io_tlb_default_mem->force
  - move set_memory_decrypted out of swiotlb_init_io_tlb_mem
  - move debugfs_dir declaration into the main CONFIG_DEBUG_FS block
  - add swiotlb_ prefix to find_slots and release_slots
  - merge the 3 alloc/free related patches
  - move the CONFIG_DMA_RESTRICTED_POOL later

v9:
Address the comments in v7 to
  - set swiotlb active pool to dev->dma_io_tlb_mem
  - get rid of get_io_tlb_mem
  - dig out the device struct for is_swiotlb_active
  - move debugfs_create_dir out of swiotlb_create_debugfs
  - do set_memory_decrypted conditionally in swiotlb_init_io_tlb_mem
  - use IS_ENABLED in kernel/dma/direct.c
  - fix redefinition of 'of_dma_set_restricted_buffer'
https://lore.kernel.org/patchwork/cover/1445081/

v8:
- Fix reserved-memory.txt and add the reg property in example.
- Fix sizeof for of_property_count_elems_of_size in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Apply Will's suggestion to try the OF node having DMA configuration in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Fix typo in the comment of drivers/of/address.c#of_dma_set_restricted_buffer.
- Add error message for PageHighMem in
  kernel/dma/swiotlb.c#rmem_swiotlb_device_init and move it to
  rmem_swiotlb_setup.
- Fix the message string in rmem_swiotlb_setup.
https://lore.kernel.org/patchwork/cover/1437112/

v7:
Fix debugfs, PageHighMem and comment style in rmem_swiotlb_device_init
https://lore.kernel.org/patchwork/cover/1431031/

v6:
Address the comments in v5
https://lore.kernel.org/patchwork/cover/1423201/

v5:
Rebase on latest linux-next
https://lore.kernel.org/patchwork/cover/1416899/

v4:
- Fix spinlock bad magic
- Use rmem->name for debugfs entry
- Address the comments in v3
https://lore.kernel.org/patchwork/cover/1378113/

v3:
Using only one reserved memory region for both streaming DMA and memory
allocation.
https://lore.kernel.org/patchwork/cover/1360992/

v2:
Building on top of swiotlb.
https://lore.kernel.org/patchwork/cover/1280705/

v1:
Using dma_map_ops.
https://lore.kernel.org/patchwork/cover/1271660/


Claire Chang (12):
  swiotlb: Refactor swiotlb init functions
  swiotlb: Refactor swiotlb_create_debugfs
  swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used
  swiotlb: Update is_swiotlb_buffer to add a struct device argument
  swiotlb: Update is_swiotlb_active to add a struct device argument
  swiotlb: Use is_dev_swiotlb_force for swiotlb data bouncing
  swiotlb: Move alloc_size to swiotlb_find_slots
  swiotlb: Refactor swiotlb_tbl_unmap_single
  swiotlb: Add restricted DMA pool initialization
  swiotlb: Add restricted DMA alloc/free support
  dt-bindings: of: Add restricted DMA pool
  of: Add plumbing for restricted DMA pool

 .../reserved-memory/reserved-memory.txt       |  36 ++-
 drivers/base/core.c                           |   4 +
 drivers/gpu/drm/i915/gem/i915_gem_internal.c  |   2 +-
 drivers/gpu/drm/nouveau/nouveau_ttm.c         |   2 +-
 drivers/iommu/dma-iommu.c                     |  12 +-
 drivers/of/address.c                          |  33 +++
 drivers/of/device.c                           |   3 +
 drivers/of/of_private.h                       |   6 +
 drivers/pci/xen-pcifront.c                    |   2 +-
 drivers/xen/swiotlb-xen.c                     |   2 +-
 include/linux/device.h                        |   4 +
 include/linux/swiotlb.h                       |  40 ++-
 kernel/dma/Kconfig                            |  14 +
 kernel/dma/direct.c                           |  60 +++--
 kernel/dma/direct.h                           |   8 +-
 kernel/dma/swiotlb.c                          | 255 +++++++++++++-----
 16 files changed, 380 insertions(+), 103 deletions(-)

-- 
2.32.0.272.g935e593368-goog


^ permalink raw reply	[flat|nested] 124+ messages in thread
* [PATCH v15 00/12] Restricted DMA
@ 2021-06-24 15:55 Claire Chang
  2021-06-24 16:42 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork
  0 siblings, 1 reply; 124+ messages in thread
From: Claire Chang @ 2021-06-24 15:55 UTC (permalink / raw)
  To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
	Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
	Christoph Hellwig, Marek Szyprowski
  Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
	Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
	bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
	heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
	Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
	xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
	bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
	jani.nikula, jxgao, joonas.lahtinen, linux-pci,
	maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
	thomas.lendacky, quic_qiancai

This series implements mitigations for lack of DMA access control on
systems without an IOMMU, which could result in the DMA accessing the
system memory at unexpected times and/or unexpected addresses, possibly
leading to data leakage or corruption.

For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is
not behind an IOMMU. As PCI-e, by design, gives the device full access to
system memory, a vulnerability in the Wi-Fi firmware could easily escalate
to a full system exploit (remote wifi exploits: [1a], [1b] that shows a
full chain of exploits; [2], [3]).

To mitigate the security concerns, we introduce restricted DMA. Restricted
DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a
specially allocated region and does memory allocation from the same region.
The feature on its own provides a basic level of protection against the DMA
overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system needs
to provide a way to restrict the DMA to a predefined memory region (this is
usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]).

[1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html
[1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html
[2] https://blade.tencent.com/en/advisories/qualpwn/
[3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/
[4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132

v15:
- Apply Will's diff (https://lore.kernel.org/patchwork/patch/1448957/#1647521)
  to fix the crash reported by Qian.
- Add Stefano's Acked-by tag for patch 01/12 from v14

v14:
- Move set_memory_decrypted before swiotlb_init_io_tlb_mem (patch 01/12, 10,12)
- Add Stefano's Acked-by tag from v13
https://lore.kernel.org/patchwork/cover/1448954/

v13:
- Fix xen-swiotlb issues
  - memset in patch 01/12
  - is_swiotlb_force_bounce in patch 06/12
- Fix the dts example typo in reserved-memory.txt
- Add Stefano and Will's Tested-by tag from v12
https://lore.kernel.org/patchwork/cover/1448001/

v12:
Split is_dev_swiotlb_force into is_swiotlb_force_bounce (patch 06/12) and
is_swiotlb_for_alloc (patch 09/12)
https://lore.kernel.org/patchwork/cover/1447254/

v11:
- Rebase against swiotlb devel/for-linus-5.14
- s/mempry/memory/g
- exchange the order of patch 09/12 and 10/12
https://lore.kernel.org/patchwork/cover/1447216/

v10:
Address the comments in v9 to
  - fix the dev->dma_io_tlb_mem assignment
  - propagate swiotlb_force setting into io_tlb_default_mem->force
  - move set_memory_decrypted out of swiotlb_init_io_tlb_mem
  - move debugfs_dir declaration into the main CONFIG_DEBUG_FS block
  - add swiotlb_ prefix to find_slots and release_slots
  - merge the 3 alloc/free related patches
  - move the CONFIG_DMA_RESTRICTED_POOL later
https://lore.kernel.org/patchwork/cover/1446882/

v9:
Address the comments in v7 to
  - set swiotlb active pool to dev->dma_io_tlb_mem
  - get rid of get_io_tlb_mem
  - dig out the device struct for is_swiotlb_active
  - move debugfs_create_dir out of swiotlb_create_debugfs
  - do set_memory_decrypted conditionally in swiotlb_init_io_tlb_mem
  - use IS_ENABLED in kernel/dma/direct.c
  - fix redefinition of 'of_dma_set_restricted_buffer'
https://lore.kernel.org/patchwork/cover/1445081/

v8:
- Fix reserved-memory.txt and add the reg property in example.
- Fix sizeof for of_property_count_elems_of_size in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Apply Will's suggestion to try the OF node having DMA configuration in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Fix typo in the comment of drivers/of/address.c#of_dma_set_restricted_buffer.
- Add error message for PageHighMem in
  kernel/dma/swiotlb.c#rmem_swiotlb_device_init and move it to
  rmem_swiotlb_setup.
- Fix the message string in rmem_swiotlb_setup.
https://lore.kernel.org/patchwork/cover/1437112/

v7:
Fix debugfs, PageHighMem and comment style in rmem_swiotlb_device_init
https://lore.kernel.org/patchwork/cover/1431031/

v6:
Address the comments in v5
https://lore.kernel.org/patchwork/cover/1423201/

v5:
Rebase on latest linux-next
https://lore.kernel.org/patchwork/cover/1416899/

v4:
- Fix spinlock bad magic
- Use rmem->name for debugfs entry
- Address the comments in v3
https://lore.kernel.org/patchwork/cover/1378113/

v3:
Using only one reserved memory region for both streaming DMA and memory
allocation.
https://lore.kernel.org/patchwork/cover/1360992/

v2:
Building on top of swiotlb.
https://lore.kernel.org/patchwork/cover/1280705/

v1:
Using dma_map_ops.
https://lore.kernel.org/patchwork/cover/1271660/

Claire Chang (12):
  swiotlb: Refactor swiotlb init functions
  swiotlb: Refactor swiotlb_create_debugfs
  swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used
  swiotlb: Update is_swiotlb_buffer to add a struct device argument
  swiotlb: Update is_swiotlb_active to add a struct device argument
  swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing
  swiotlb: Move alloc_size to swiotlb_find_slots
  swiotlb: Refactor swiotlb_tbl_unmap_single
  swiotlb: Add restricted DMA alloc/free support
  swiotlb: Add restricted DMA pool initialization
  dt-bindings: of: Add restricted DMA pool
  of: Add plumbing for restricted DMA pool

 .../reserved-memory/reserved-memory.txt       |  36 ++-
 drivers/base/core.c                           |   4 +
 drivers/gpu/drm/i915/gem/i915_gem_internal.c  |   2 +-
 drivers/gpu/drm/nouveau/nouveau_ttm.c         |   2 +-
 drivers/iommu/dma-iommu.c                     |  12 +-
 drivers/of/address.c                          |  33 +++
 drivers/of/device.c                           |   3 +
 drivers/of/of_private.h                       |   6 +
 drivers/pci/xen-pcifront.c                    |   2 +-
 drivers/xen/swiotlb-xen.c                     |   4 +-
 include/linux/device.h                        |   4 +
 include/linux/swiotlb.h                       |  53 +++-
 kernel/dma/Kconfig                            |  14 +
 kernel/dma/direct.c                           |  59 ++--
 kernel/dma/direct.h                           |   8 +-
 kernel/dma/swiotlb.c                          | 251 +++++++++++++-----
 16 files changed, 390 insertions(+), 103 deletions(-)

-- 
2.32.0.288.g62a8d224e6-goog


^ permalink raw reply	[flat|nested] 124+ messages in thread
* [PATCH v14 00/12] Restricted DMA
@ 2021-06-19  3:40 Claire Chang
  2021-06-19  4:05 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork
  0 siblings, 1 reply; 124+ messages in thread
From: Claire Chang @ 2021-06-19  3:40 UTC (permalink / raw)
  To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
	Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
	Christoph Hellwig, Marek Szyprowski
  Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
	Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
	bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
	heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
	Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
	xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
	bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
	jani.nikula, jxgao, joonas.lahtinen, linux-pci,
	maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom,
	thomas.lendacky

This series implements mitigations for lack of DMA access control on
systems without an IOMMU, which could result in the DMA accessing the
system memory at unexpected times and/or unexpected addresses, possibly
leading to data leakage or corruption.

For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is
not behind an IOMMU. As PCI-e, by design, gives the device full access to
system memory, a vulnerability in the Wi-Fi firmware could easily escalate
to a full system exploit (remote wifi exploits: [1a], [1b] that shows a
full chain of exploits; [2], [3]).

To mitigate the security concerns, we introduce restricted DMA. Restricted
DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a
specially allocated region and does memory allocation from the same region.
The feature on its own provides a basic level of protection against the DMA
overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system needs
to provide a way to restrict the DMA to a predefined memory region (this is
usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]).

[1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html
[1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html
[2] https://blade.tencent.com/en/advisories/qualpwn/
[3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/
[4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132

v14:
- Move set_memory_decrypted before swiotlb_init_io_tlb_mem (patch 01/12, 10,12)
- Add Stefano's Acked-by tag from v13

v13:
- Fix xen-swiotlb issues
  - memset in patch 01/12
  - is_swiotlb_force_bounce in patch 06/12
- Fix the dts example typo in reserved-memory.txt
- Add Stefano and Will's Tested-by tag from v12
https://lore.kernel.org/patchwork/cover/1448001/

v12:
Split is_dev_swiotlb_force into is_swiotlb_force_bounce (patch 06/12) and
is_swiotlb_for_alloc (patch 09/12)
https://lore.kernel.org/patchwork/cover/1447254/

v11:
- Rebase against swiotlb devel/for-linus-5.14
- s/mempry/memory/g
- exchange the order of patch 09/12 and 10/12
https://lore.kernel.org/patchwork/cover/1447216/

v10:
Address the comments in v9 to
  - fix the dev->dma_io_tlb_mem assignment
  - propagate swiotlb_force setting into io_tlb_default_mem->force
  - move set_memory_decrypted out of swiotlb_init_io_tlb_mem
  - move debugfs_dir declaration into the main CONFIG_DEBUG_FS block
  - add swiotlb_ prefix to find_slots and release_slots
  - merge the 3 alloc/free related patches
  - move the CONFIG_DMA_RESTRICTED_POOL later
https://lore.kernel.org/patchwork/cover/1446882/

v9:
Address the comments in v7 to
  - set swiotlb active pool to dev->dma_io_tlb_mem
  - get rid of get_io_tlb_mem
  - dig out the device struct for is_swiotlb_active
  - move debugfs_create_dir out of swiotlb_create_debugfs
  - do set_memory_decrypted conditionally in swiotlb_init_io_tlb_mem
  - use IS_ENABLED in kernel/dma/direct.c
  - fix redefinition of 'of_dma_set_restricted_buffer'
https://lore.kernel.org/patchwork/cover/1445081/

v8:
- Fix reserved-memory.txt and add the reg property in example.
- Fix sizeof for of_property_count_elems_of_size in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Apply Will's suggestion to try the OF node having DMA configuration in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Fix typo in the comment of drivers/of/address.c#of_dma_set_restricted_buffer.
- Add error message for PageHighMem in
  kernel/dma/swiotlb.c#rmem_swiotlb_device_init and move it to
  rmem_swiotlb_setup.
- Fix the message string in rmem_swiotlb_setup.
https://lore.kernel.org/patchwork/cover/1437112/

v7:
Fix debugfs, PageHighMem and comment style in rmem_swiotlb_device_init
https://lore.kernel.org/patchwork/cover/1431031/

v6:
Address the comments in v5
https://lore.kernel.org/patchwork/cover/1423201/

v5:
Rebase on latest linux-next
https://lore.kernel.org/patchwork/cover/1416899/

v4:
- Fix spinlock bad magic
- Use rmem->name for debugfs entry
- Address the comments in v3
https://lore.kernel.org/patchwork/cover/1378113/

v3:
Using only one reserved memory region for both streaming DMA and memory
allocation.
https://lore.kernel.org/patchwork/cover/1360992/

v2:
Building on top of swiotlb.
https://lore.kernel.org/patchwork/cover/1280705/

v1:
Using dma_map_ops.
https://lore.kernel.org/patchwork/cover/1271660/


Claire Chang (12):
  swiotlb: Refactor swiotlb init functions
  swiotlb: Refactor swiotlb_create_debugfs
  swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used
  swiotlb: Update is_swiotlb_buffer to add a struct device argument
  swiotlb: Update is_swiotlb_active to add a struct device argument
  swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing
  swiotlb: Move alloc_size to swiotlb_find_slots
  swiotlb: Refactor swiotlb_tbl_unmap_single
  swiotlb: Add restricted DMA alloc/free support
  swiotlb: Add restricted DMA pool initialization
  dt-bindings: of: Add restricted DMA pool
  of: Add plumbing for restricted DMA pool

 .../reserved-memory/reserved-memory.txt       |  36 ++-
 drivers/base/core.c                           |   4 +
 drivers/gpu/drm/i915/gem/i915_gem_internal.c  |   2 +-
 drivers/gpu/drm/nouveau/nouveau_ttm.c         |   2 +-
 drivers/iommu/dma-iommu.c                     |  12 +-
 drivers/of/address.c                          |  33 +++
 drivers/of/device.c                           |   3 +
 drivers/of/of_private.h                       |   6 +
 drivers/pci/xen-pcifront.c                    |   2 +-
 drivers/xen/swiotlb-xen.c                     |   4 +-
 include/linux/device.h                        |   4 +
 include/linux/swiotlb.h                       |  51 +++-
 kernel/dma/Kconfig                            |  14 +
 kernel/dma/direct.c                           |  59 +++--
 kernel/dma/direct.h                           |   8 +-
 kernel/dma/swiotlb.c                          | 250 +++++++++++++-----
 16 files changed, 387 insertions(+), 103 deletions(-)

-- 
2.32.0.288.g62a8d224e6-goog


^ permalink raw reply	[flat|nested] 124+ messages in thread
* [PATCH v13 00/12] Restricted DMA
@ 2021-06-17  6:26 Claire Chang
  2021-06-17  6:33 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork
  0 siblings, 1 reply; 124+ messages in thread
From: Claire Chang @ 2021-06-17  6:26 UTC (permalink / raw)
  To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
	Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
	Christoph Hellwig, Marek Szyprowski
  Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
	Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
	bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
	heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
	Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
	xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
	bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
	jani.nikula, jxgao, joonas.lahtinen, linux-pci,
	maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom

This series implements mitigations for lack of DMA access control on
systems without an IOMMU, which could result in the DMA accessing the
system memory at unexpected times and/or unexpected addresses, possibly
leading to data leakage or corruption.

For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is
not behind an IOMMU. As PCI-e, by design, gives the device full access to
system memory, a vulnerability in the Wi-Fi firmware could easily escalate
to a full system exploit (remote wifi exploits: [1a], [1b] that shows a
full chain of exploits; [2], [3]).

To mitigate the security concerns, we introduce restricted DMA. Restricted
DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a
specially allocated region and does memory allocation from the same region.
The feature on its own provides a basic level of protection against the DMA
overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system needs
to provide a way to restrict the DMA to a predefined memory region (this is
usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]).

[1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html
[1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html
[2] https://blade.tencent.com/en/advisories/qualpwn/
[3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/
[4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132

v13:
- Fix xen-swiotlb issues
  - memset in patch 01/12
  - is_swiotlb_force_bounce in patch 06/12
- Fix the dts example typo in reserved-memory.txt
- Add Stefano and Will's Tested-by tag from v12

v12:
Split is_dev_swiotlb_force into is_swiotlb_force_bounce (patch 06/12) and
is_swiotlb_for_alloc (patch 09/12)
https://lore.kernel.org/patchwork/cover/1447254/

v11:
- Rebase against swiotlb devel/for-linus-5.14
- s/mempry/memory/g
- exchange the order of patch 09/12 and 10/12
https://lore.kernel.org/patchwork/cover/1447216/

v10:
Address the comments in v9 to
  - fix the dev->dma_io_tlb_mem assignment
  - propagate swiotlb_force setting into io_tlb_default_mem->force
  - move set_memory_decrypted out of swiotlb_init_io_tlb_mem
  - move debugfs_dir declaration into the main CONFIG_DEBUG_FS block
  - add swiotlb_ prefix to find_slots and release_slots
  - merge the 3 alloc/free related patches
  - move the CONFIG_DMA_RESTRICTED_POOL later
https://lore.kernel.org/patchwork/cover/1446882/

v9:
Address the comments in v7 to
  - set swiotlb active pool to dev->dma_io_tlb_mem
  - get rid of get_io_tlb_mem
  - dig out the device struct for is_swiotlb_active
  - move debugfs_create_dir out of swiotlb_create_debugfs
  - do set_memory_decrypted conditionally in swiotlb_init_io_tlb_mem
  - use IS_ENABLED in kernel/dma/direct.c
  - fix redefinition of 'of_dma_set_restricted_buffer'
https://lore.kernel.org/patchwork/cover/1445081/

v8:
- Fix reserved-memory.txt and add the reg property in example.
- Fix sizeof for of_property_count_elems_of_size in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Apply Will's suggestion to try the OF node having DMA configuration in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Fix typo in the comment of drivers/of/address.c#of_dma_set_restricted_buffer.
- Add error message for PageHighMem in
  kernel/dma/swiotlb.c#rmem_swiotlb_device_init and move it to
  rmem_swiotlb_setup.
- Fix the message string in rmem_swiotlb_setup.
https://lore.kernel.org/patchwork/cover/1437112/

v7:
Fix debugfs, PageHighMem and comment style in rmem_swiotlb_device_init
https://lore.kernel.org/patchwork/cover/1431031/

v6:
Address the comments in v5
https://lore.kernel.org/patchwork/cover/1423201/

v5:
Rebase on latest linux-next
https://lore.kernel.org/patchwork/cover/1416899/

v4:
- Fix spinlock bad magic
- Use rmem->name for debugfs entry
- Address the comments in v3
https://lore.kernel.org/patchwork/cover/1378113/

v3:
Using only one reserved memory region for both streaming DMA and memory
allocation.
https://lore.kernel.org/patchwork/cover/1360992/

v2:
Building on top of swiotlb.
https://lore.kernel.org/patchwork/cover/1280705/

v1:
Using dma_map_ops.
https://lore.kernel.org/patchwork/cover/1271660/

Claire Chang (12):
  swiotlb: Refactor swiotlb init functions
  swiotlb: Refactor swiotlb_create_debugfs
  swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used
  swiotlb: Update is_swiotlb_buffer to add a struct device argument
  swiotlb: Update is_swiotlb_active to add a struct device argument
  swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing
  swiotlb: Move alloc_size to swiotlb_find_slots
  swiotlb: Refactor swiotlb_tbl_unmap_single
  swiotlb: Add restricted DMA alloc/free support
  swiotlb: Add restricted DMA pool initialization
  dt-bindings: of: Add restricted DMA pool
  of: Add plumbing for restricted DMA pool

 .../reserved-memory/reserved-memory.txt       |  36 ++-
 drivers/base/core.c                           |   4 +
 drivers/gpu/drm/i915/gem/i915_gem_internal.c  |   2 +-
 drivers/gpu/drm/nouveau/nouveau_ttm.c         |   2 +-
 drivers/iommu/dma-iommu.c                     |  12 +-
 drivers/of/address.c                          |  33 +++
 drivers/of/device.c                           |   3 +
 drivers/of/of_private.h                       |   6 +
 drivers/pci/xen-pcifront.c                    |   2 +-
 drivers/xen/swiotlb-xen.c                     |   4 +-
 include/linux/device.h                        |   4 +
 include/linux/swiotlb.h                       |  51 +++-
 kernel/dma/Kconfig                            |  14 +
 kernel/dma/direct.c                           |  59 +++--
 kernel/dma/direct.h                           |   8 +-
 kernel/dma/swiotlb.c                          | 250 +++++++++++++-----
 16 files changed, 387 insertions(+), 103 deletions(-)

-- 
2.32.0.288.g62a8d224e6-goog


^ permalink raw reply	[flat|nested] 124+ messages in thread
* [PATCH v12 00/12] Restricted DMA
@ 2021-06-16  6:21 Claire Chang
  2021-06-16  7:35 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork
  0 siblings, 1 reply; 124+ messages in thread
From: Claire Chang @ 2021-06-16  6:21 UTC (permalink / raw)
  To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
	Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
	Christoph Hellwig, Marek Szyprowski
  Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
	Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
	bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
	heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
	Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
	xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
	bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
	jani.nikula, jxgao, joonas.lahtinen, linux-pci,
	maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom

This series implements mitigations for lack of DMA access control on
systems without an IOMMU, which could result in the DMA accessing the
system memory at unexpected times and/or unexpected addresses, possibly
leading to data leakage or corruption.

For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is
not behind an IOMMU. As PCI-e, by design, gives the device full access to
system memory, a vulnerability in the Wi-Fi firmware could easily escalate
to a full system exploit (remote wifi exploits: [1a], [1b] that shows a
full chain of exploits; [2], [3]).

To mitigate the security concerns, we introduce restricted DMA. Restricted
DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a
specially allocated region and does memory allocation from the same region.
The feature on its own provides a basic level of protection against the DMA
overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system needs
to provide a way to restrict the DMA to a predefined memory region (this is
usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]).

[1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html
[1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html
[2] https://blade.tencent.com/en/advisories/qualpwn/
[3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/
[4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132

v12:
Split is_dev_swiotlb_force into is_swiotlb_force_bounce (patch 06/12) and
is_swiotlb_for_alloc (patch 09/12)

v11:
- Rebase against swiotlb devel/for-linus-5.14
- s/mempry/memory/g
- exchange the order of patch 09/12 and 10/12
https://lore.kernel.org/patchwork/cover/1447216/

v10:
Address the comments in v9 to
  - fix the dev->dma_io_tlb_mem assignment
  - propagate swiotlb_force setting into io_tlb_default_mem->force
  - move set_memory_decrypted out of swiotlb_init_io_tlb_mem
  - move debugfs_dir declaration into the main CONFIG_DEBUG_FS block
  - add swiotlb_ prefix to find_slots and release_slots
  - merge the 3 alloc/free related patches
  - move the CONFIG_DMA_RESTRICTED_POOL later
https://lore.kernel.org/patchwork/cover/1446882/

v9:
Address the comments in v7 to
  - set swiotlb active pool to dev->dma_io_tlb_mem
  - get rid of get_io_tlb_mem
  - dig out the device struct for is_swiotlb_active
  - move debugfs_create_dir out of swiotlb_create_debugfs
  - do set_memory_decrypted conditionally in swiotlb_init_io_tlb_mem
  - use IS_ENABLED in kernel/dma/direct.c
  - fix redefinition of 'of_dma_set_restricted_buffer'
https://lore.kernel.org/patchwork/cover/1445081/

v8:
- Fix reserved-memory.txt and add the reg property in example.
- Fix sizeof for of_property_count_elems_of_size in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Apply Will's suggestion to try the OF node having DMA configuration in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Fix typo in the comment of drivers/of/address.c#of_dma_set_restricted_buffer.
- Add error message for PageHighMem in
  kernel/dma/swiotlb.c#rmem_swiotlb_device_init and move it to
  rmem_swiotlb_setup.
- Fix the message string in rmem_swiotlb_setup.
https://lore.kernel.org/patchwork/cover/1437112/

v7:
Fix debugfs, PageHighMem and comment style in rmem_swiotlb_device_init
https://lore.kernel.org/patchwork/cover/1431031/

v6:
Address the comments in v5
https://lore.kernel.org/patchwork/cover/1423201/

v5:
Rebase on latest linux-next
https://lore.kernel.org/patchwork/cover/1416899/

v4:
- Fix spinlock bad magic
- Use rmem->name for debugfs entry
- Address the comments in v3
https://lore.kernel.org/patchwork/cover/1378113/

v3:
Using only one reserved memory region for both streaming DMA and memory
allocation.
https://lore.kernel.org/patchwork/cover/1360992/

v2:
Building on top of swiotlb.
https://lore.kernel.org/patchwork/cover/1280705/

v1:
Using dma_map_ops.
https://lore.kernel.org/patchwork/cover/1271660/


Claire Chang (12):
  swiotlb: Refactor swiotlb init functions
  swiotlb: Refactor swiotlb_create_debugfs
  swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used
  swiotlb: Update is_swiotlb_buffer to add a struct device argument
  swiotlb: Update is_swiotlb_active to add a struct device argument
  swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing
  swiotlb: Move alloc_size to swiotlb_find_slots
  swiotlb: Refactor swiotlb_tbl_unmap_single
  swiotlb: Add restricted DMA alloc/free support
  swiotlb: Add restricted DMA pool initialization
  dt-bindings: of: Add restricted DMA pool
  of: Add plumbing for restricted DMA pool

 .../reserved-memory/reserved-memory.txt       |  36 ++-
 drivers/base/core.c                           |   4 +
 drivers/gpu/drm/i915/gem/i915_gem_internal.c  |   2 +-
 drivers/gpu/drm/nouveau/nouveau_ttm.c         |   2 +-
 drivers/iommu/dma-iommu.c                     |  12 +-
 drivers/of/address.c                          |  33 +++
 drivers/of/device.c                           |   3 +
 drivers/of/of_private.h                       |   6 +
 drivers/pci/xen-pcifront.c                    |   2 +-
 drivers/xen/swiotlb-xen.c                     |   2 +-
 include/linux/device.h                        |   4 +
 include/linux/swiotlb.h                       |  51 +++-
 kernel/dma/Kconfig                            |  14 +
 kernel/dma/direct.c                           |  59 +++--
 kernel/dma/direct.h                           |   8 +-
 kernel/dma/swiotlb.c                          | 249 +++++++++++++-----
 16 files changed, 385 insertions(+), 102 deletions(-)

-- 
2.32.0.272.g935e593368-goog


^ permalink raw reply	[flat|nested] 124+ messages in thread
* [PATCH v11 00/12] Restricted DMA
@ 2021-06-16  3:52 Claire Chang
  2021-06-16  7:34 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork
  0 siblings, 1 reply; 124+ messages in thread
From: Claire Chang @ 2021-06-16  3:52 UTC (permalink / raw)
  To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
	Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
	Christoph Hellwig, Marek Szyprowski
  Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
	Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
	bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
	heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
	Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
	xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
	bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
	jani.nikula, jxgao, joonas.lahtinen, linux-pci,
	maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom

This series implements mitigations for lack of DMA access control on
systems without an IOMMU, which could result in the DMA accessing the
system memory at unexpected times and/or unexpected addresses, possibly
leading to data leakage or corruption.

For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is
not behind an IOMMU. As PCI-e, by design, gives the device full access to
system memory, a vulnerability in the Wi-Fi firmware could easily escalate
to a full system exploit (remote wifi exploits: [1a], [1b] that shows a
full chain of exploits; [2], [3]).

To mitigate the security concerns, we introduce restricted DMA. Restricted
DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a
specially allocated region and does memory allocation from the same region.
The feature on its own provides a basic level of protection against the DMA
overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system needs
to provide a way to restrict the DMA to a predefined memory region (this is
usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]).

[1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html
[1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html
[2] https://blade.tencent.com/en/advisories/qualpwn/
[3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/
[4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132

v11:
- Rebase against swiotlb devel/for-linus-5.14
- s/mempry/memory/g
- exchange the order of patch 09/12 and 10/12
https://lore.kernel.org/patchwork/cover/1446882/

v10:
Address the comments in v9 to
  - fix the dev->dma_io_tlb_mem assignment
  - propagate swiotlb_force setting into io_tlb_default_mem->force
  - move set_memory_decrypted out of swiotlb_init_io_tlb_mem
  - move debugfs_dir declaration into the main CONFIG_DEBUG_FS block
  - add swiotlb_ prefix to find_slots and release_slots
  - merge the 3 alloc/free related patches
  - move the CONFIG_DMA_RESTRICTED_POOL later

v9:
Address the comments in v7 to
  - set swiotlb active pool to dev->dma_io_tlb_mem
  - get rid of get_io_tlb_mem
  - dig out the device struct for is_swiotlb_active
  - move debugfs_create_dir out of swiotlb_create_debugfs
  - do set_memory_decrypted conditionally in swiotlb_init_io_tlb_mem
  - use IS_ENABLED in kernel/dma/direct.c
  - fix redefinition of 'of_dma_set_restricted_buffer'
https://lore.kernel.org/patchwork/cover/1445081/

v8:
- Fix reserved-memory.txt and add the reg property in example.
- Fix sizeof for of_property_count_elems_of_size in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Apply Will's suggestion to try the OF node having DMA configuration in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Fix typo in the comment of drivers/of/address.c#of_dma_set_restricted_buffer.
- Add error message for PageHighMem in
  kernel/dma/swiotlb.c#rmem_swiotlb_device_init and move it to
  rmem_swiotlb_setup.
- Fix the message string in rmem_swiotlb_setup.
https://lore.kernel.org/patchwork/cover/1437112/

v7:
Fix debugfs, PageHighMem and comment style in rmem_swiotlb_device_init
https://lore.kernel.org/patchwork/cover/1431031/

v6:
Address the comments in v5
https://lore.kernel.org/patchwork/cover/1423201/

v5:
Rebase on latest linux-next
https://lore.kernel.org/patchwork/cover/1416899/

v4:
- Fix spinlock bad magic
- Use rmem->name for debugfs entry
- Address the comments in v3
https://lore.kernel.org/patchwork/cover/1378113/

v3:
Using only one reserved memory region for both streaming DMA and memory
allocation.
https://lore.kernel.org/patchwork/cover/1360992/

v2:
Building on top of swiotlb.
https://lore.kernel.org/patchwork/cover/1280705/

v1:
Using dma_map_ops.
https://lore.kernel.org/patchwork/cover/1271660/

Claire Chang (12):
  swiotlb: Refactor swiotlb init functions
  swiotlb: Refactor swiotlb_create_debugfs
  swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used
  swiotlb: Update is_swiotlb_buffer to add a struct device argument
  swiotlb: Update is_swiotlb_active to add a struct device argument
  swiotlb: Use is_dev_swiotlb_force for swiotlb data bouncing
  swiotlb: Move alloc_size to swiotlb_find_slots
  swiotlb: Refactor swiotlb_tbl_unmap_single
  swiotlb: Add restricted DMA alloc/free support
  swiotlb: Add restricted DMA pool initialization
  dt-bindings: of: Add restricted DMA pool
  of: Add plumbing for restricted DMA pool

 .../reserved-memory/reserved-memory.txt       |  36 ++-
 drivers/base/core.c                           |   4 +
 drivers/gpu/drm/i915/gem/i915_gem_internal.c  |   2 +-
 drivers/gpu/drm/nouveau/nouveau_ttm.c         |   2 +-
 drivers/iommu/dma-iommu.c                     |  12 +-
 drivers/of/address.c                          |  33 +++
 drivers/of/device.c                           |   3 +
 drivers/of/of_private.h                       |   6 +
 drivers/pci/xen-pcifront.c                    |   2 +-
 drivers/xen/swiotlb-xen.c                     |   2 +-
 include/linux/device.h                        |   4 +
 include/linux/swiotlb.h                       |  40 ++-
 kernel/dma/Kconfig                            |  14 +
 kernel/dma/direct.c                           |  60 +++--
 kernel/dma/direct.h                           |   8 +-
 kernel/dma/swiotlb.c                          | 255 +++++++++++++-----
 16 files changed, 380 insertions(+), 103 deletions(-)

-- 
2.32.0.272.g935e593368-goog


^ permalink raw reply	[flat|nested] 124+ messages in thread
* [PATCH v9 00/14] Restricted DMA
@ 2021-06-11 15:26 Claire Chang
  2021-06-11 17:37 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork
  0 siblings, 1 reply; 124+ messages in thread
From: Claire Chang @ 2021-06-11 15:26 UTC (permalink / raw)
  To: Rob Herring, mpe, Joerg Roedel, Will Deacon, Frank Rowand,
	Konrad Rzeszutek Wilk, boris.ostrovsky, jgross,
	Christoph Hellwig, Marek Szyprowski
  Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
	Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
	bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
	heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
	Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
	xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
	bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
	jani.nikula, jxgao, joonas.lahtinen, linux-pci,
	maarten.lankhorst, matthew.auld, rodrigo.vivi, thomas.hellstrom

This series implements mitigations for lack of DMA access control on
systems without an IOMMU, which could result in the DMA accessing the
system memory at unexpected times and/or unexpected addresses, possibly
leading to data leakage or corruption.

For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is
not behind an IOMMU. As PCI-e, by design, gives the device full access to
system memory, a vulnerability in the Wi-Fi firmware could easily escalate
to a full system exploit (remote wifi exploits: [1a], [1b] that shows a
full chain of exploits; [2], [3]).

To mitigate the security concerns, we introduce restricted DMA. Restricted
DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a
specially allocated region and does memory allocation from the same region.
The feature on its own provides a basic level of protection against the DMA
overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system needs
to provide a way to restrict the DMA to a predefined memory region (this is
usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]).

[1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html
[1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html
[2] https://blade.tencent.com/en/advisories/qualpwn/
[3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/
[4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132

v9:
Address the comments in v7 to
  - set swiotlb active pool to dev->dma_io_tlb_mem
  - get rid of get_io_tlb_mem
  - dig out the device struct for is_swiotlb_active
  - move debugfs_create_dir out of swiotlb_create_debugfs
  - do set_memory_decrypted conditionally in swiotlb_init_io_tlb_mem
  - use IS_ENABLED in kernel/dma/direct.c
  - fix redefinition of 'of_dma_set_restricted_buffer'

v8:
- Fix reserved-memory.txt and add the reg property in example.
- Fix sizeof for of_property_count_elems_of_size in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Apply Will's suggestion to try the OF node having DMA configuration in
  drivers/of/address.c#of_dma_set_restricted_buffer.
- Fix typo in the comment of drivers/of/address.c#of_dma_set_restricted_buffer.
- Add error message for PageHighMem in
  kernel/dma/swiotlb.c#rmem_swiotlb_device_init and move it to
  rmem_swiotlb_setup.
- Fix the message string in rmem_swiotlb_setup.
https://lore.kernel.org/patchwork/cover/1437112/

v7:
Fix debugfs, PageHighMem and comment style in rmem_swiotlb_device_init
https://lore.kernel.org/patchwork/cover/1431031/

v6:
Address the comments in v5
https://lore.kernel.org/patchwork/cover/1423201/

v5:
Rebase on latest linux-next
https://lore.kernel.org/patchwork/cover/1416899/

v4:
- Fix spinlock bad magic
- Use rmem->name for debugfs entry
- Address the comments in v3
https://lore.kernel.org/patchwork/cover/1378113/

v3:
Using only one reserved memory region for both streaming DMA and memory
allocation.
https://lore.kernel.org/patchwork/cover/1360992/

v2:
Building on top of swiotlb.
https://lore.kernel.org/patchwork/cover/1280705/

v1:
Using dma_map_ops.
https://lore.kernel.org/patchwork/cover/1271660/


Claire Chang (14):
  swiotlb: Refactor swiotlb init functions
  swiotlb: Refactor swiotlb_create_debugfs
  swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used
  swiotlb: Add restricted DMA pool initialization
  swiotlb: Update is_swiotlb_buffer to add a struct device argument
  swiotlb: Update is_swiotlb_active to add a struct device argument
  swiotlb: Bounce data from/to restricted DMA pool if available
  swiotlb: Move alloc_size to find_slots
  swiotlb: Refactor swiotlb_tbl_unmap_single
  dma-direct: Add a new wrapper __dma_direct_free_pages()
  swiotlb: Add restricted DMA alloc/free support.
  dma-direct: Allocate memory from restricted DMA pool if available
  dt-bindings: of: Add restricted DMA pool
  of: Add plumbing for restricted DMA pool

 .../reserved-memory/reserved-memory.txt       |  36 ++-
 drivers/gpu/drm/i915/gem/i915_gem_internal.c  |   2 +-
 drivers/gpu/drm/nouveau/nouveau_ttm.c         |   2 +-
 drivers/iommu/dma-iommu.c                     |  12 +-
 drivers/of/address.c                          |  33 +++
 drivers/of/device.c                           |   6 +
 drivers/of/of_private.h                       |   6 +
 drivers/pci/xen-pcifront.c                    |   2 +-
 drivers/xen/swiotlb-xen.c                     |   2 +-
 include/linux/device.h                        |   4 +
 include/linux/swiotlb.h                       |  45 +++-
 kernel/dma/Kconfig                            |  14 +
 kernel/dma/direct.c                           |  62 +++--
 kernel/dma/direct.h                           |   9 +-
 kernel/dma/swiotlb.c                          | 242 +++++++++++++-----
 15 files changed, 376 insertions(+), 101 deletions(-)

-- 
2.32.0.272.g935e593368-goog


^ permalink raw reply	[flat|nested] 124+ messages in thread
* [PATCH v5 00/16] Restricted DMA
@ 2021-04-22  8:14 Claire Chang
  2021-04-22  9:37 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork
  0 siblings, 1 reply; 124+ messages in thread
From: Claire Chang @ 2021-04-22  8:14 UTC (permalink / raw)
  To: Joerg Roedel, Will Deacon, Frank Rowand, Konrad Rzeszutek Wilk,
	boris.ostrovsky, jgross, Christoph Hellwig, Marek Szyprowski
  Cc: benh, paulus, list@263.net:IOMMU DRIVERS, sstabellini,
	Robin Murphy, grant.likely, xypron.glpk, Thierry Reding, mingo,
	bauerman, peterz, Greg KH, Saravana Kannan, Rafael J . Wysocki,
	heikki.krogerus, Andy Shevchenko, Randy Dunlap, Dan Williams,
	Bartosz Golaszewski, linux-devicetree, lkml, linuxppc-dev,
	xen-devel, Nicolas Boichat, Jim Quinlan, tfiga, bskeggs,
	bhelgaas, chris, tientzu, daniel, airlied, dri-devel, intel-gfx,
	jani.nikula, jxgao, joonas.lahtinen, linux-pci,
	maarten.lankhorst, matthew.auld, nouveau, rodrigo.vivi,
	thomas.hellstrom

This series implements mitigations for lack of DMA access control on
systems without an IOMMU, which could result in the DMA accessing the
system memory at unexpected times and/or unexpected addresses, possibly
leading to data leakage or corruption.

For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is
not behind an IOMMU. As PCI-e, by design, gives the device full access to
system memory, a vulnerability in the Wi-Fi firmware could easily escalate
to a full system exploit (remote wifi exploits: [1a], [1b] that shows a
full chain of exploits; [2], [3]).

To mitigate the security concerns, we introduce restricted DMA. Restricted
DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a
specially allocated region and does memory allocation from the same region.
The feature on its own provides a basic level of protection against the DMA
overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system needs
to provide a way to restrict the DMA to a predefined memory region (this is
usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]).

[1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html
[1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html
[2] https://blade.tencent.com/en/advisories/qualpwn/
[3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/
[4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132

v5:
  Rebase on latest linux-next

v4:
  - Fix spinlock bad magic
  - Use rmem->name for debugfs entry
  - Address the comments in v3

v3:
  Using only one reserved memory region for both streaming DMA and memory
  allocation.
  https://lore.kernel.org/patchwork/cover/1360992/

v2:
  Building on top of swiotlb.
  https://lore.kernel.org/patchwork/cover/1280705/

v1:
  Using dma_map_ops.
  https://lore.kernel.org/patchwork/cover/1271660/

Claire Chang (16):
  swiotlb: Fix the type of index
  swiotlb: Refactor swiotlb init functions
  swiotlb: Refactor swiotlb_create_debugfs
  swiotlb: Add DMA_RESTRICTED_POOL
  swiotlb: Add restricted DMA pool initialization
  swiotlb: Add a new get_io_tlb_mem getter
  swiotlb: Update is_swiotlb_buffer to add a struct device argument
  swiotlb: Update is_swiotlb_active to add a struct device argument
  swiotlb: Bounce data from/to restricted DMA pool if available
  swiotlb: Move alloc_size to find_slots
  swiotlb: Refactor swiotlb_tbl_unmap_single
  dma-direct: Add a new wrapper __dma_direct_free_pages()
  swiotlb: Add restricted DMA alloc/free support.
  dma-direct: Allocate memory from restricted DMA pool if available
  dt-bindings: of: Add restricted DMA pool
  of: Add plumbing for restricted DMA pool

 .../reserved-memory/reserved-memory.txt       |  24 ++
 drivers/gpu/drm/i915/gem/i915_gem_internal.c  |   2 +-
 drivers/gpu/drm/nouveau/nouveau_ttm.c         |   2 +-
 drivers/iommu/dma-iommu.c                     |  12 +-
 drivers/of/address.c                          |  25 ++
 drivers/of/device.c                           |   3 +
 drivers/of/of_private.h                       |   5 +
 drivers/pci/xen-pcifront.c                    |   2 +-
 drivers/xen/swiotlb-xen.c                     |   2 +-
 include/linux/device.h                        |   4 +
 include/linux/swiotlb.h                       |  41 ++-
 kernel/dma/Kconfig                            |  14 +
 kernel/dma/direct.c                           |  57 +++--
 kernel/dma/direct.h                           |   9 +-
 kernel/dma/swiotlb.c                          | 242 +++++++++++++-----
 15 files changed, 347 insertions(+), 97 deletions(-)

-- 
2.31.1.368.gbe11c130af-goog


^ permalink raw reply	[flat|nested] 124+ messages in thread

end of thread, other threads:[~2021-06-24 16:42 UTC | newest]

Thread overview: 124+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-06-15 13:26 [PATCH v10 00/12] Restricted DMA Claire Chang
2021-06-15 13:26 ` [Intel-gfx] " Claire Chang
2021-06-15 13:26 ` Claire Chang
2021-06-15 13:26 ` Claire Chang
2021-06-15 13:26 ` Claire Chang
2021-06-15 13:27 ` [PATCH v10 01/12] swiotlb: Refactor swiotlb init functions Claire Chang
2021-06-15 13:27   ` [Intel-gfx] " Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:37   ` Christoph Hellwig
2021-06-15 13:37     ` [Intel-gfx] " Christoph Hellwig
2021-06-15 13:37     ` Christoph Hellwig
2021-06-15 13:37     ` Christoph Hellwig
2021-06-15 13:27 ` [PATCH v10 02/12] swiotlb: Refactor swiotlb_create_debugfs Claire Chang
2021-06-15 13:27   ` [Intel-gfx] " Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:38   ` Christoph Hellwig
2021-06-15 13:38     ` [Intel-gfx] " Christoph Hellwig
2021-06-15 13:38     ` Christoph Hellwig
2021-06-15 13:38     ` Christoph Hellwig
2021-06-15 13:27 ` [PATCH v10 03/12] swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used Claire Chang
2021-06-15 13:27   ` [Intel-gfx] " Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:38   ` Christoph Hellwig
2021-06-15 13:38     ` [Intel-gfx] " Christoph Hellwig
2021-06-15 13:38     ` Christoph Hellwig
2021-06-15 13:38     ` Christoph Hellwig
2021-06-15 22:21   ` Konrad Rzeszutek Wilk
2021-06-15 22:21     ` [Intel-gfx] " Konrad Rzeszutek Wilk
2021-06-15 22:21     ` Konrad Rzeszutek Wilk
2021-06-15 22:21     ` Konrad Rzeszutek Wilk
2021-06-15 22:21     ` Konrad Rzeszutek Wilk
2021-06-15 13:27 ` [PATCH v10 04/12] swiotlb: Update is_swiotlb_buffer to add a struct device argument Claire Chang
2021-06-15 13:27   ` [Intel-gfx] " Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:38   ` Christoph Hellwig
2021-06-15 13:38     ` [Intel-gfx] " Christoph Hellwig
2021-06-15 13:38     ` Christoph Hellwig
2021-06-15 13:38     ` Christoph Hellwig
2021-06-15 13:27 ` [PATCH v10 05/12] swiotlb: Update is_swiotlb_active " Claire Chang
2021-06-15 13:27   ` [Intel-gfx] " Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:39   ` Christoph Hellwig
2021-06-15 13:39     ` [Intel-gfx] " Christoph Hellwig
2021-06-15 13:39     ` Christoph Hellwig
2021-06-15 13:39     ` Christoph Hellwig
2021-06-15 13:27 ` [PATCH v10 06/12] swiotlb: Use is_dev_swiotlb_force for swiotlb data bouncing Claire Chang
2021-06-15 13:27   ` [Intel-gfx] " Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:39   ` Christoph Hellwig
2021-06-15 13:39     ` [Intel-gfx] " Christoph Hellwig
2021-06-15 13:39     ` Christoph Hellwig
2021-06-15 13:39     ` Christoph Hellwig
2021-06-15 13:27 ` [PATCH v10 07/12] swiotlb: Move alloc_size to swiotlb_find_slots Claire Chang
2021-06-15 13:27   ` [Intel-gfx] " Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:39   ` Christoph Hellwig
2021-06-15 13:39     ` [Intel-gfx] " Christoph Hellwig
2021-06-15 13:39     ` Christoph Hellwig
2021-06-15 13:39     ` Christoph Hellwig
2021-06-15 13:27 ` [PATCH v10 08/12] swiotlb: Refactor swiotlb_tbl_unmap_single Claire Chang
2021-06-15 13:27   ` [Intel-gfx] " Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:40   ` Christoph Hellwig
2021-06-15 13:40     ` [Intel-gfx] " Christoph Hellwig
2021-06-15 13:40     ` Christoph Hellwig
2021-06-15 13:40     ` Christoph Hellwig
2021-06-15 13:27 ` [PATCH v10 09/12] swiotlb: Add restricted DMA pool initialization Claire Chang
2021-06-15 13:27   ` [Intel-gfx] " Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:40   ` Christoph Hellwig
2021-06-15 13:40     ` [Intel-gfx] " Christoph Hellwig
2021-06-15 13:40     ` Christoph Hellwig
2021-06-15 13:40     ` Christoph Hellwig
2021-06-15 13:27 ` [PATCH v10 10/12] swiotlb: Add restricted DMA alloc/free support Claire Chang
2021-06-15 13:27   ` [Intel-gfx] " Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:42   ` Christoph Hellwig
2021-06-15 13:42     ` [Intel-gfx] " Christoph Hellwig
2021-06-15 13:42     ` Christoph Hellwig
2021-06-15 13:42     ` Christoph Hellwig
2021-06-15 13:27 ` [PATCH v10 11/12] dt-bindings: of: Add restricted DMA pool Claire Chang
2021-06-15 13:27   ` [Intel-gfx] " Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27 ` [PATCH v10 12/12] of: Add plumbing for " Claire Chang
2021-06-15 13:27   ` [Intel-gfx] " Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 13:27   ` Claire Chang
2021-06-15 14:04 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for Restricted DMA Patchwork
2021-06-16  3:55 ` [PATCH v10 00/12] " Claire Chang
2021-06-16  3:55   ` Claire Chang
2021-06-16  3:55   ` [Intel-gfx] " Claire Chang
2021-06-16  3:55   ` Claire Chang
2021-06-16  3:55   ` Claire Chang
2021-06-16  3:55   ` Claire Chang
  -- strict thread matches above, loose matches on Subject: below --
2021-06-24 15:55 [PATCH v15 " Claire Chang
2021-06-24 16:42 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork
2021-06-19  3:40 [PATCH v14 00/12] " Claire Chang
2021-06-19  4:05 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork
2021-06-17  6:26 [PATCH v13 00/12] " Claire Chang
2021-06-17  6:33 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork
2021-06-16  6:21 [PATCH v12 00/12] " Claire Chang
2021-06-16  7:35 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork
2021-06-16  3:52 [PATCH v11 00/12] " Claire Chang
2021-06-16  7:34 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork
2021-06-11 15:26 [PATCH v9 00/14] " Claire Chang
2021-06-11 17:37 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork
2021-04-22  8:14 [PATCH v5 00/16] " Claire Chang
2021-04-22  9:37 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for " Patchwork

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