In the Linux kernel, the following vulnerability has been resolved:
KVM: SEV: Pin source page for write when adding CPUID data for SNP guest
When populating a guest_memfd instance with the initial CPUID data for an
SNP guest, acquire a writable pin on the source page as KVM will write back
the "correct" CPUID information if the userspace provided data is rejected
by trusted firmware. Because KVM writes to the source page using a kernel
mapping, pinning for read could result in KVM clobbering read-only memory.
Note, well-behaved VMMs are unlikely to be affected, as CPUID information
is almost always dynamically generated by userspace, i.e. it's unlikely for
the CPUID information to be backed by a read-only mapping.
[sean: rewrite shortlog and changelog, tag for stable@]
In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Clear __hyp_running_vcpu when flushing the pKVM hyp vCPU
flush_hyp_vcpu() copies the host vCPU context into the hyp's private
vCPU on every run. ctxt_to_vcpu() expects a guest context to have a
NULL __hyp_running_vcpu, which is only ever set on the host context, so
that it resolves the vCPU via container_of(). While this is generally
the case, flush_hyp_vcpu() copies the context verbatim and does not
enforce this, so a value provided by the host is dereferenced at EL2
(host -> EL2).
Fix by clearing __hyp_running_vcpu after the copy.
In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Bound used_lrs when flushing the pKVM hyp vCPU
flush_hyp_vcpu() copies the host vGIC state into the hyp's private vCPU
on every run. The vGIC list register save and restore use used_lrs as
their loop bound and expect it to stay within the number of implemented
list registers. While this is generally the case, flush_hyp_vcpu()
copies vgic_v3 verbatim and does not enforce this, so a value provided
by the host is used at EL2 to index vgic_lr[] and access ICH_LR<n>_EL2
(host -> EL2).
Fix by clamping used_lrs to the number of implemented list registers
after the copy, as the trusted path already does in
vgic_flush_lr_state(). The number of implemented list registers is
constant after init, so it is replicated once from
kvm_vgic_global_state.nr_lr into hyp_gicv3_nr_lr rather than read on
every entry.
In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: nv: Avoid dereferencing NULL VNCR pseudo-TLB
VNCR TLB invalidation occurs from MMU notifiers or TLBI instructions,
and either can race against a vcpu not being onlined yet (no pseudo-TLB
allocated). Similarly, the TLB might be invalid, and the invalidation
should be skipped in this case.
Both kvm_invalidate_vncr_ipa() and kvm_invalidate_vncr_va() are
expected to perform the same checks, except that the latter doesn't
check for the allocation and blindly dereferences the pointer.
Solve this by introducing a new iterator built on top of the usual
kvm_for_each_vcpu() that checks for both of the above conditions,
and convert the two users to it.
In the Linux kernel, the following vulnerability has been resolved:
iommufd: Set upper bounds on cache invalidation entry_num and entry_len
iommufd_hwpt_invalidate() takes a user-controlled entry_num and entry_len,
each bounded only by U32_MAX. An entry_len beyond the kernel's struct size
makes the copy helper verify the extra bytes are zero, scanning that excess
in one uninterruptible pass; a multi-gigabyte value over zeroed user memory
trips the soft-lockup watchdog.
A large entry_num is the other half, driving the backend invalidation loop
with no reschedule. The VT-d nested handler, for one, copies each entry and
flushes caches per iteration, pinning the CPU on a non-preemptible kernel.
Cap both in the ioctl. entry_len is held under PAGE_SIZE, above any request
struct, and entry_num under 1 << 19, the order of a hardware invalidation
queue and well beyond any real batch, bounding the per-call loop length.
In the Linux kernel, the following vulnerability has been resolved:
Input: synaptics-rmi4 - bound the F30 keymap to the GPIO/LED count
rmi_f30_map_gpios() allocates gpioled_key_map with
min(gpioled_count, TRACKSTICK_RANGE_END) == at most 6 entries, but
rmi_f30_attention() iterates the full f30->gpioled_count (device query
register, range 0..31) and dereferences gpioled_key_map[i], and
input->keycodemax is set to the full gpioled_count while input->keycode
points at the 6-entry allocation.
A device that reports gpioled_count > 6 with GPIO support enabled
therefore causes an out-of-bounds read on the attention interrupt and
out-of-bounds read/write through the EVIOCGKEYCODE/EVIOCSKEYCODE ioctls,
which bound the index only against keycodemax. This is the same defect
as the F3A handler, which was copied from F30.
Size the keymap for the full gpioled_count; the mapping loop still
assigns only the first min(gpioled_count, TRACKSTICK_RANGE_END) entries.
In the Linux kernel, the following vulnerability has been resolved:
Input: synaptics-rmi4 - bound the F3A keymap to the GPIO count
rmi_f3a_initialize() takes the GPIO count from the device query register
(f3a->gpio_count = buf & RMI_F3A_GPIO_COUNT, range 0..127).
rmi_f3a_map_gpios() then allocates gpio_key_map with
min(gpio_count, TRACKSTICK_RANGE_END) == at most 6 entries, but
rmi_f3a_attention() iterates the full gpio_count and dereferences
gpio_key_map[i], and input->keycodemax is set to the full gpio_count
while input->keycode points at the 6-entry allocation.
A device that reports gpio_count > 6 therefore causes an out-of-bounds
read of gpio_key_map[] on every attention interrupt, and out-of-bounds
accesses through the input core's default keymap ioctls: EVIOCGKEYCODE
reads past the buffer (leaking adjacent slab memory to user space) and
EVIOCSKEYCODE writes a caller-controlled value past it, for any process
able to open the evdev node, since input_default_getkeycode() and
input_default_setkeycode() only bound the index against keycodemax.
Size the keymap for the full gpio_count. The mapping loop is unchanged:
it still assigns only the first min(gpio_count, TRACKSTICK_RANGE_END)
entries; the remaining slots stay KEY_RESERVED (devm_kcalloc zero-fills)
and are skipped when reporting.
In the Linux kernel, the following vulnerability has been resolved:
i2c: imx-lpi2c: mark I2C adapter when hardware is powered down
On some i.MX platforms, certain I2C client drivers keep a periodic
workqueue which continues to trigger I2C transfers.
During system suspend/resume, there exists a time window between:
- suspend_noirq and the system entering suspend
- the system starting to resume and resume_noirq
In this window, the I2C controller resources such as clock and pinctrl
may already be disabled or not yet restored.
If a workqueue triggers an I2C transfer in this period, the driver
attempts to access I2C registers while the hardware resources are
unavailable, which may lead to system hang.
Mark the I2C adapter as suspended during noirq suspend and block new
transfers until resume, ensuring that I2C transfers are only issued
when hardware resources are available.
In the Linux kernel, the following vulnerability has been resolved:
i2c: core: fix adapter deregistration race
Adapters can be looked up by their id using i2c_get_adapter() which
takes a reference to the embedded struct device.
Remove the adapter from the IDR before tearing it down during
deregistration (and on registration failure) to make sure its resources
are not accessed after having been freed (e.g. the device name).
In the Linux kernel, the following vulnerability has been resolved:
fpga: dfl-afu: validate DMA mapping length in afu_dma_map_region()
afu_ioctl_dma_map() accepts a 64-bit length from userspace via
DFL_FPGA_PORT_DMA_MAP ioctl without an upper bound check. The value
is passed to afu_dma_pin_pages() where npages is derived as
length >> PAGE_SHIFT and passed to pin_user_pages_fast() which takes
int nr_pages, causing implicit truncation if length is very large.
Validate map.length at the ioctl entry point before calling
afu_dma_map_region(), rejecting values whose page count exceeds
INT_MAX.