KVM: x86: hyper-v: Clamp stimer deadline to avoid livelock
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: hyper-v: Clamp stimer deadline to avoid livelock
Fix an issue where userspace or the guest can program an Hyper-V
synthetic timer to have a deadline in the past via integer overflow,
preventing the CPU from making progress and triggering an RCU stall.
Hyper-V's SynIC exposes 4 per-vCPU synthetic timers to the
guest, which are emulated by KVM. Each is programmed through the
HV_X64_MSR_STIMERi_CONFIG and HV_X64_MSR_STIMERi_COUNT MSRs. Depending
on CONFIG, COUNT represents either the absolute expiration time or the
period of a periodic timer, both expressed in 100ns
In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: Fix length check __import_wp_info()
struct kvm_hw_breakpoint::len is a __u64 that is fully controlled by user
space. This is then assigned to wp_info->len, which is an int. The bounds
check is done on the truncated value while the allocation uses the
untruncated one:
wp_info->len = bp_data->len;
[...]
if (wp_info->len < 0 || wp_info->len > MAX_WP_SIZE)
return -EINVAL;
wp_info->old_data = kmalloc(bp_data->len, GFP_KERNEL_ACCOUNT);
Use the validated value for the allocation as intended. Without this
fix userspace can trigger >4GB allocations which will fai
KVM: s390: Fix memory leak in guest debug handling
In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: Fix memory leak in guest debug handling
bp_data is freed only for the error case by kfree(bp_data).
Every successful KVM_SET_GUEST_DEBUG will leak bp_data.
KVM: s390: Fix old_data leak in guest debug error path
In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: Fix old_data leak in guest debug error path
__import_wp_info() allocates a per-watchpoint old_data buffer to back up
the original guest memory contents. If a later watchpoint of the same
KVM_SET_GUEST_DEBUG request fails to import, kvm_s390_import_bp_data()
jumps to the error label, which frees the wp_info array but not the
old_data buffers of the entries that were imported successfully. Up to
MAX_BP_COUNT - 1 buffers of up to MAX_WP_SIZE bytes are leaked per failed
request, and the request can be repeated.
Create error handling for cleaning up all created old_d
In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: Free guest debug data on vcpu destroy
kvm_s390_clear_bp_data() is only called from
kvm_arch_vcpu_ioctl_set_guest_debug(), i.e. when user space changes or
disables debugging. A vCPU that is destroyed while hardware breakpoints
are still armed - the normal case when the VMM just exits or crashes -
leaks hw_bp_info, hw_wp_info and all old_data buffers, since generic KVM
frees the vCPU right after kvm_arch_vcpu_destroy().
That is bounded by MAX_BP_COUNT entries, so roughly 8 KiB per vCPU, but
it is unbounded over VM lifetimes. The allocations are
GFP_KERNEL_ACCOUNT,
KVM: s390: Take srcu when importing watchpoint data
In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: Take srcu when importing watchpoint data
__import_wp_info() backs up the original guest memory contents of a
watchpoint with read_guest_abs(), which is kvm_read_guest() and therefore
resolves the memslot via __kvm_memslots(). That requires kvm->srcu (or
kvm->slots_lock) to be held, otherwise a concurrent memslot update can
free the memslots array under us once its SRCU grace period has elapsed.
As this is not fast path, following lock ordering (mutex first, then
srcu) take the big hammer and hold the srcu for the full import.
KVM: s390: Zero initialize data structures for inject_pfault_token
In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: Zero initialize data structures for inject_pfault_token
__kvm_inject_pfault_token() only sets .type and .u.ext.ext_params2 of
the on-stack struct kvm_s390_irq but the full ext substructure is copied
into the cpu local variable on inject. ext_params and pad contain stale
stack values.
Interrupt delivery only uses ext_params2, so nothing leaks to the guest,
but a host user can use the migration ioctls to get to the data.
Fix by zero-initializing the irq struct.
Do the same for the inti data structure.
KVM: s390: Fix memory corruption by not reinjecting CK machine checks
In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: Fix memory corruption by not reinjecting CK machine checks
Channel-subsystem damage machine checks are for the host channel
subsystem. The guest channel subsystem is emulated in the userspace VMM.
There is no point in forwarding such machine checks into the guest.
This also simplifies the machine check reinjection and avoids kfree of a
stack variable as reported by sashiko. There might be still machine
checks that have the ck bit set with another bit (like instruction
damage), mask out the CK bit in s390_backup_mcck_info(), like the CP and
ED bits already are.
KVM: arm64: vgic-v3: take an LPI reference in vgic_v3_save_pending_tables
In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: vgic-v3: take an LPI reference in vgic_v3_save_pending_tables
vgic_v3_save_pending_tables() iterates dist->lpi_xa using xa_for_each()
and dereferences the returned struct vgic_irq in the loop body without
holding a reference on the LPI.
The xarray iterator only provides temporary RCU coverage while looking up
the current entry. That is not sufficient for this loop body, which reads
fields from struct vgic_irq and performs guest memory accesses before the
iteration completes.
A concurrent path can trigger this race: the irqfd cached injection path
(vgic_its_inj
KVM: arm64: vgic-its: Don't dereference a NULL collection on ITT save
In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: vgic-its: Don't dereference a NULL collection on ITT save
MAPC with V=0 drops ite->collection but leaves the ITE on the device's
ITT list, and vgic_its_save_ite() dereferences it unconditionally. A
guest that issues MAPD, MAPTI and then MAPC(V=0) therefore oopses the
host when the VMM issues KVM_DEV_ARM_ITS_SAVE_TABLES to migrate it.
That sequence is UNPREDICTABLE per the architecture, but KVM already
handles the resulting state in the translate, MOVI and DISCARD paths.
Save a zeroed entry, which vgic_its_restore_ite() reads back as
invalid. Skipping the ITE in
media: airspy: use vb2_video_unregister_device() on disconnect to fix NULL deref
In the Linux kernel, the following vulnerability has been resolved:
media: airspy: use vb2_video_unregister_device() on disconnect to fix NULL deref
airspy_disconnect() clears s->udev under v4l2_lock, but
airspy_stop_streaming() unconditionally calls airspy_ctrl_msg() and
airspy_free_stream_bufs() afterwards. If a streaming user closes the
device after disconnect, stop_streaming() runs and dereferences the
NULL s->udev:
airspy_stop_streaming()
airspy_ctrl_msg(s, CMD_RECEIVER_MODE, 0, 0, NULL, 0)
usb_sndctrlpipe(s->udev, 0) /* NULL deref */
airspy_free_stream_bufs(s)
usb_free_coherent(s->udev, ...) /* NULL
media: cec: disable delayed work before freeing an interrupted transmit
In the Linux kernel, the following vulnerability has been resolved:
media: cec: disable delayed work before freeing an interrupted transmit
cec_transmit_msg_fh() drops adap->lock to wait for a blocking transmit in
wait_for_completion_killable(). If that wait is interrupted by a signal,
cancel_delayed_work_sync() can run before the CEC kthread arms the reply
timeout via schedule_delayed_work(&data->work) in cec_transmit_done_ts().
The work is then armed after the cancel, and the data is freed with its
delayed_work still pending:
ODEBUG: free active (active state 0) object: ... hint: cec_wait_timeout
Use disable_delayed_work_sync(): it ca
In the Linux kernel, the following vulnerability has been resolved:
media: cec: Serialize exclusive follower delivery
cec_receive_notify() reads the exclusive follower pointer without the
adapter lock. Serialize the no-follower check and message delivery
against mode changes and release.
media: cedrus: fix memory leak in cedrus_init_ctrls()
In the Linux kernel, the following vulnerability has been resolved:
media: cedrus: fix memory leak in cedrus_init_ctrls()
In cedrus_init_ctrls(), the V4L2 control handler is initialized before
allocating memory for ctx->ctrls. If this allocation fails, the function
returns -ENOMEM without freeing the previously allocated handler
resources, leading to a memory leak.
Fix this by calling v4l2_ctrl_handler_free() on the ctx->ctrls allocation
failure path.
The bug was first flagged by an experimental analysis tool we are
developing for kernel memory-management bugs while analyzing
v6.13-rc1. The tool is still under development and is not yet p
media: cobalt: Avoid freeing ALSA private data twice
In the Linux kernel, the following vulnerability has been resolved:
media: cobalt: Avoid freeing ALSA private data twice
snd_cobalt_card_create() stores cobsc in sc->private_data and installs
snd_cobalt_card_private_free() as sc->private_free. From that point,
snd_card_free(sc) releases cobsc through the ALSA card cleanup path.
If cobalt_alsa_init() fails after snd_cobalt_card_create(), the
err_exit_free path calls snd_card_free(sc) and then kfree(cobsc). That
second free releases the same object again.
Remove the explicit kfree(cobsc) and leave ownership with the ALSA card.
This issue was found by a static analysis checker and confirmed
media: cx23885: cancel NetUP CI work before teardown
In the Linux kernel, the following vulnerability has been resolved:
media: cx23885: cancel NetUP CI work before teardown
netup_ci_exit() frees a netup_ci_state while its work item,
netup_read_ci_status(), may still be pending or running on the system
workqueue. The worker obtains the state with container_of() and
dereferences it, so it must not outlive the state.
netup_ci_init() queues the initial status read, and CI GPIO interrupts
subsequently queue the same work from netup_ci_slot_status(). During
remove, cx23885_finidev() calls free_irq() before the CI device is
unregistered. free_irq() prevents further IRQ handlers from running,
but d
In the Linux kernel, the following vulnerability has been resolved:
media: em28xx: defer audio-only extension registration
The audio-only path registers extensions while probing the primary device.
For a dual-TS board, this happens before dev_next is created. The duplicate
device inherits is_audio_only and is then independently inserted into
em28xx_devlist.
The list is intended to contain only primary devices: extension operations
reach the secondary device through dev_next. The independently linked
secondary can be freed during disconnect while its list node remains
reachable, resulting in a use-after-free.
Defer audio-only extension reg
media: em28xx: fix use-after-free of dev_next->devlist on disconnect
In the Linux kernel, the following vulnerability has been resolved:
media: em28xx: fix use-after-free of dev_next->devlist on disconnect
When a device with has_dual_ts=1 is probed and the is_audio_only path
is taken, both dev and dev->dev_next are added to the global
em28xx_devlist via em28xx_init_extension(). However, during disconnect,
em28xx_close_extension(dev) only calls list_del(&dev->devlist), leaving
dev->dev_next->devlist still linked in the global list. When dev_next is
subsequently freed via kref_put(), its devlist entry becomes a dangling
pointer in em28xx_devlist. The next device probe that calls
em28xx_init_extension() trigger
media: go7007: defer the ALSA v4l2 put until card release
In the Linux kernel, the following vulnerability has been resolved:
media: go7007: defer the ALSA v4l2 put until card release
go7007_snd_init() already takes a v4l2_device reference for the ALSA
side, but go7007_snd_remove() drops it immediately after calling
snd_card_free_when_closed().
That is too early when a userspace process still has the capture PCM open.
The ALSA card and its PCM callbacks remain alive until the last file is
closed, so the release path can still reach struct go7007 through
pcm->private_data and call go7007_snd_hw_free() after the V4L2 release path
has freed the object.
Move the matching v4l2_device_put() to the ALS
media: i2c: ov7740: fix use-after-destroy in remove
In the Linux kernel, the following vulnerability has been resolved:
media: i2c: ov7740: fix use-after-destroy in remove
The ov7740_remove() function had a severe teardown order bug where it
destroyed the driver's mutex before freeing the V4L2 control handler
which relies on that mutex, leading to a use-after-destroy kernel panic.
Furthermore, the driver explicitly called v4l2_ctrl_handler_free() and
mutex_destroy() sequentially, but then called ov7740_free_controls()
which invokes both of them a second time, resulting in a double-free.
This patch fixes the issue by unregistering the subdevice first, and
relying exclusively on ov7740_free_c