struct vfio_cdx_device carries three fields that track whether MSI has
been configured: vdev->cdx_irqs (the allocated vector array), vdev->
msi_count (the array length), and vdev->config_msi (a boolean flag).
The three are set together when vfio_cdx_msi_enable() succeeds and
cleared together by vfio_cdx_msi_disable(). However, the error paths
in vfio_cdx_msi_enable() free the cdx_irqs allocation on failure
without resetting the pointer, leaving it stale and skewed from the
other two fields until the next enable call overwrites it.
Clear vdev->cdx_irqs to NULL alongside the kfree() in both error paths
so the pointer consistently reflects the configured state. With that
invariant restored and access to the MSI state serialized by
cdx_irqs_lock, vdev->config_msi is fully redundant with
(vdev->cdx_irqs != NULL). Drop the config_msi field and switch all
readers to test cdx_irqs directly.
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Alex Williamson <alex.williamson@nvidia.com>
Acked-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Link: https://lore.kernel.org/r/20260417202800.88287-4-alex.williamson@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
vfio_cdx_set_msi_trigger() reads vdev->config_msi and operates on the
vdev->cdx_irqs array based on its value, but provides no serialization
against concurrent VFIO_DEVICE_SET_IRQS ioctls. Two callers can race
such that one observes config_msi as set while another clears it and
frees cdx_irqs via vfio_cdx_msi_disable(), resulting in a use-after-free
of the cdx_irqs array.
Add a cdx_irqs_lock mutex to struct vfio_cdx_device and acquire it in
vfio_cdx_set_msi_trigger(), which is the single chokepoint through
which all updates to config_msi, cdx_irqs, and msi_count flow, covering
both the ioctl path and the close-device cleanup path. This keeps the
test of config_msi atomic with the subsequent enable, disable, or
trigger operations.
Drop the pre-call !cdx_irqs test from vfio_cdx_irqs_cleanup() as part
of this change: the optimization it provided is redundant with the
!config_msi early-return inside vfio_cdx_msi_disable(), and leaving the
test in place would be an unsynchronized read of state the new lock is
meant to protect.
Fixes: 848e447e00 ("vfio/cdx: add interrupt support")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Alex Williamson <alex.williamson@nvidia.com>
Acked-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Link: https://lore.kernel.org/r/20260417202800.88287-3-alex.williamson@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
Add validation to ensure MSI is configured before accessing cdx_irqs
array in vfio_cdx_set_msi_trigger(). Without this check, userspace
can trigger a NULL pointer dereference by calling VFIO_DEVICE_SET_IRQS
with VFIO_IRQ_SET_DATA_BOOL or VFIO_IRQ_SET_DATA_NONE flags before
ever setting up interrupts via VFIO_IRQ_SET_DATA_EVENTFD.
The vfio_cdx_msi_enable() function allocates the cdx_irqs array and
sets config_msi to 1 only when called through the EVENTFD path. The
trigger loop (for DATA_BOOL/DATA_NONE) assumed this had already been
done, but there was no enforcement of this call ordering.
This matches the protection used in the PCI VFIO driver where
vfio_pci_set_msi_trigger() checks irq_is() before the trigger loop.
Fixes: 848e447e00 ("vfio/cdx: add interrupt support")
Cc: stable@vger.kernel.org
Signed-off-by: Prasanna Kumar T S M <ptsm@linux.microsoft.com>
Acked-by: Nipun Gupta <nipun.gupta@amd.com>
Signed-off-by: Alex Williamson <alex.williamson@nvidia.com>
Acked-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Link: https://lore.kernel.org/r/20260417202800.88287-2-alex.williamson@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
Remove the duplicate code and change info to a pointer. caps are not used.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Pranjal Shrivastava <praan@google.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/21-v2-2a9e24d62f1b+e10a-vfio_get_region_info_op_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
Change the signature of vfio_cdx_ioctl_get_region_info() and hook it to
the op.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Pranjal Shrivastava <praan@google.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/11-v2-2a9e24d62f1b+e10a-vfio_get_region_info_op_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
Support the following ioctls for CDX devices:
- VFIO_DEVICE_GET_IRQ_INFO
- VFIO_DEVICE_SET_IRQS
This allows user to set an eventfd for cdx device interrupts and
trigger this interrupt eventfd from userspace.
All CDX device interrupts are MSIs. The MSIs are allocated from the
CDX-MSI domain.
Signed-off-by: Nipun Gupta <nipun.gupta@amd.com>
Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Link: https://lore.kernel.org/r/20240423111021.1686144-2-nipun.gupta@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Here is the big set of char/misc and other small driver subsystem
changes for 6.7-rc1. Included in here are:
- IIO subsystem driver updates and additions (largest part of this
pull request)
- FPGA subsystem driver updates
- Counter subsystem driver updates
- ICC subsystem driver updates
- extcon subsystem driver updates
- mei driver updates and additions
- nvmem subsystem driver updates and additions
- comedi subsystem dependency fixes
- parport driver fixups
- cdx subsystem driver and core updates
- splice support for /dev/zero and /dev/full
- other smaller driver cleanups
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc updates from Greg KH:
"Here is the big set of char/misc and other small driver subsystem
changes for 6.7-rc1. Included in here are:
- IIO subsystem driver updates and additions (largest part of this
pull request)
- FPGA subsystem driver updates
- Counter subsystem driver updates
- ICC subsystem driver updates
- extcon subsystem driver updates
- mei driver updates and additions
- nvmem subsystem driver updates and additions
- comedi subsystem dependency fixes
- parport driver fixups
- cdx subsystem driver and core updates
- splice support for /dev/zero and /dev/full
- other smaller driver cleanups
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (326 commits)
cdx: add sysfs for subsystem, class and revision
cdx: add sysfs for bus reset
cdx: add support for bus enable and disable
cdx: Register cdx bus as a device on cdx subsystem
cdx: Create symbol namespaces for cdx subsystem
cdx: Introduce lock to protect controller ops
cdx: Remove cdx controller list from cdx bus system
dts: ti: k3-am625-beagleplay: Add beaglecc1352
greybus: Add BeaglePlay Linux Driver
dt-bindings: net: Add ti,cc1352p7
dt-bindings: eeprom: at24: allow NVMEM cells based on old syntax
dt-bindings: nvmem: SID: allow NVMEM cells based on old syntax
Revert "nvmem: add new config option"
MAINTAINERS: coresight: Add missing Coresight files
misc: pci_endpoint_test: Add deviceID for J721S2 PCIe EP device support
firmware: xilinx: Move EXPORT_SYMBOL_GPL next to zynqmp_pm_feature definition
uacce: make uacce_class constant
ocxl: make ocxl_class constant
cxl: make cxl_class constant
misc: phantom: make phantom_class constant
...
Create CDX_BUS and CDX_BUS_CONTROLLER symbol namespace for cdx bus
subsystem. CDX controller modules are required to import symbols from
CDX_BUS_CONTROLLER namespace and other than controller modules to
import from CDX_BUS namespace.
Signed-off-by: Abhijit Gangurde <abhijit.gangurde@amd.com>
Link: https://lore.kernel.org/r/20231017160505.10640-4-abhijit.gangurde@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When building with clang, there is a warning (or error with
CONFIG_WERROR=y) due to a bitwise AND and logical NOT in
vfio_cdx_bm_ctrl():
drivers/vfio/cdx/main.c:77:6: error: logical not is only applied to the left hand side of this bitwise operator [-Werror,-Wlogical-not-parentheses]
77 | if (!vdev->flags & BME_SUPPORT)
| ^ ~
drivers/vfio/cdx/main.c:77:6: note: add parentheses after the '!' to evaluate the bitwise operator first
77 | if (!vdev->flags & BME_SUPPORT)
| ^
| ( )
drivers/vfio/cdx/main.c:77:6: note: add parentheses around left hand side expression to silence this warning
77 | if (!vdev->flags & BME_SUPPORT)
| ^
| ( )
1 error generated.
Add the parentheses as suggested in the first note, which is clearly
what was intended here.
Closes: https://github.com/ClangBuiltLinux/linux/issues/1939
Fixes: 8a97ab9b8b ("vfio-cdx: add bus mastering device feature support")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20231002-vfio-cdx-logical-not-parentheses-v1-1-a8846c7adfb6@kernel.org
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Support Bus master enable and disable on VFIO-CDX devices using
VFIO_DEVICE_FEATURE_BUS_MASTER flag over VFIO_DEVICE_FEATURE IOCTL.
Co-developed-by: Shubham Rohila <shubham.rohila@amd.com>
Signed-off-by: Shubham Rohila <shubham.rohila@amd.com>
Signed-off-by: Nipun Gupta <nipun.gupta@amd.com>
Link: https://lore.kernel.org/r/20230915045423.31630-3-nipun.gupta@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The cdx_driver_register() will set "THIS_MODULE" to driver.owner when
register a cdx_driver driver, so it is redundant initialization to set
driver.owner in the statement. Remove it for clean code.
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Acked-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Link: https://lore.kernel.org/r/20230808020937.2975196-1-lizetao1@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio-cdx driver enables IOCTLs for user space to query
MMIO regions for CDX devices and mmap them. This change
also adds support for reset of CDX devices. With VFIO
enabled on CDX devices, user-space applications can also
exercise DMA securely via IOMMU on these devices.
This change adds the VFIO CDX driver and enables the following
ioctls for CDX devices:
- VFIO_DEVICE_GET_INFO:
- VFIO_DEVICE_GET_REGION_INFO
- VFIO_DEVICE_RESET
Signed-off-by: Nipun Gupta <nipun.gupta@amd.com>
Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Tested-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Link: https://lore.kernel.org/r/20230531124557.11009-1-nipun.gupta@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
