Linux: >> Linux Kernel >> 6.6.144 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_conn: fix potential UAF in set_cig_params_sync
hci_conn lookup and field access must be covered by hdev lock in
set_cig_params_sync, otherwise it's possible it is freed concurrently.
Take hdev lock to prevent hci_conn from being deleted or modified
concurrently. Just RCU lock is not suitable here, as we also want to
avoid "tearing" in the configuration.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-05-01
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix incorrect pruning due to atomic fetch precision tracking
When backtrack_insn encounters a BPF_STX instruction with BPF_ATOMIC
and BPF_FETCH, the src register (or r0 for BPF_CMPXCHG) also acts as
a destination, thus receiving the old value from the memory location.
The current backtracking logic does not account for this. It treats
atomic fetch operations the same as regular stores where the src
register is only an input. This leads the backtrack_insn to fail to
propagate precision to the stack location, which is then not marked
as precise!
Later, the verifier's path pruning can incorrectly consider two states
equivalent when they differ in terms of stack state. Meaning, two
branches can be treated as equivalent and thus get pruned when they
should not be seen as such.
Fix it as follows: Extend the BPF_LDX handling in backtrack_insn to
also cover atomic fetch operations via is_atomic_fetch_insn() helper.
When the fetch dst register is being tracked for precision, clear it,
and propagate precision over to the stack slot. For non-stack memory,
the precision walk stops at the atomic instruction, same as regular
BPF_LDX. This covers all fetch variants.
Before:
0: (b7) r1 = 8 ; R1=8
1: (7b) *(u64 *)(r10 -8) = r1 ; R1=8 R10=fp0 fp-8=8
2: (b7) r2 = 0 ; R2=0
3: (db) r2 = atomic64_fetch_add((u64 *)(r10 -8), r2) ; R2=8 R10=fp0 fp-8=mmmmmmmm
4: (bf) r3 = r10 ; R3=fp0 R10=fp0
5: (0f) r3 += r2
mark_precise: frame0: last_idx 5 first_idx 0 subseq_idx -1
mark_precise: frame0: regs=r2 stack= before 4: (bf) r3 = r10
mark_precise: frame0: regs=r2 stack= before 3: (db) r2 = atomic64_fetch_add((u64 *)(r10 -8), r2)
mark_precise: frame0: regs=r2 stack= before 2: (b7) r2 = 0
6: R2=8 R3=fp8
6: (b7) r0 = 0 ; R0=0
7: (95) exit
After:
0: (b7) r1 = 8 ; R1=8
1: (7b) *(u64 *)(r10 -8) = r1 ; R1=8 R10=fp0 fp-8=8
2: (b7) r2 = 0 ; R2=0
3: (db) r2 = atomic64_fetch_add((u64 *)(r10 -8), r2) ; R2=8 R10=fp0 fp-8=mmmmmmmm
4: (bf) r3 = r10 ; R3=fp0 R10=fp0
5: (0f) r3 += r2
mark_precise: frame0: last_idx 5 first_idx 0 subseq_idx -1
mark_precise: frame0: regs=r2 stack= before 4: (bf) r3 = r10
mark_precise: frame0: regs=r2 stack= before 3: (db) r2 = atomic64_fetch_add((u64 *)(r10 -8), r2)
mark_precise: frame0: regs= stack=-8 before 2: (b7) r2 = 0
mark_precise: frame0: regs= stack=-8 before 1: (7b) *(u64 *)(r10 -8) = r1
mark_precise: frame0: regs=r1 stack= before 0: (b7) r1 = 8
6: R2=8 R3=fp8
6: (b7) r0 = 0 ; R0=0
7: (95) exit
CVSS Score
7.8
EPSS Score
0.001
Published
2026-05-01
In the Linux kernel, the following vulnerability has been resolved:
bpf: Reject sleepable kprobe_multi programs at attach time
kprobe.multi programs run in atomic/RCU context and cannot sleep.
However, bpf_kprobe_multi_link_attach() did not validate whether the
program being attached had the sleepable flag set, allowing sleepable
helpers such as bpf_copy_from_user() to be invoked from a non-sleepable
context.
This causes a "sleeping function called from invalid context" splat:
BUG: sleeping function called from invalid context at ./include/linux/uaccess.h:169
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1787, name: sudo
preempt_count: 1, expected: 0
RCU nest depth: 2, expected: 0
Fix this by rejecting sleepable programs early in
bpf_kprobe_multi_link_attach(), before any further processing.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-01
In the Linux kernel, the following vulnerability has been resolved:
ALSA: ctxfi: Check the error for index mapping
The ctxfi driver blindly assumed a proper value returned from
daio_device_index(), but it's not always true. Add a proper error
check to deal with the error from the function.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-01
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_event: move wake reason storage into validated event handlers
hci_store_wake_reason() is called from hci_event_packet() immediately
after stripping the HCI event header but before hci_event_func()
enforces the per-event minimum payload length from hci_ev_table.
This means a short HCI event frame can reach bacpy() before any bounds
check runs.
Rather than duplicating skb parsing and per-event length checks inside
hci_store_wake_reason(), move wake-address storage into the individual
event handlers after their existing event-length validation has
succeeded. Convert hci_store_wake_reason() into a small helper that only
stores an already-validated bdaddr while the caller holds hci_dev_lock().
Use the same helper after hci_event_func() with a NULL address to
preserve the existing unexpected-wake fallback semantics when no
validated event handler records a wake address.
Annotate the helper with __must_hold(&hdev->lock) and add
lockdep_assert_held(&hdev->lock) so future call paths keep the lock
contract explicit.
Call the helper from hci_conn_request_evt(), hci_conn_complete_evt(),
hci_sync_conn_complete_evt(), le_conn_complete_evt(),
hci_le_adv_report_evt(), hci_le_ext_adv_report_evt(),
hci_le_direct_adv_report_evt(), hci_le_pa_sync_established_evt(), and
hci_le_past_received_evt().
CVSS Score
8.1
EPSS Score
0.002
Published
2026-05-01
In the Linux kernel, the following vulnerability has been resolved:
drm/i915/dsi: Don't do DSC horizontal timing adjustments in command mode
Stop adjusting the horizontal timing values based on the
compression ratio in command mode. Bspec seems to be telling
us to do this only in video mode, and this is also how the
Windows driver does things.
This should also fix a div-by-zero on some machines because
the adjusted htotal ends up being so small that we end up with
line_time_us==0 when trying to determine the vtotal value in
command mode.
Note that this doesn't actually make the display on the
Huawei Matebook E work, but at least the kernel no longer
explodes when the driver loads.
(cherry picked from commit 0b475e91ecc2313207196c6d7fd5c53e1a878525)
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-01
In the Linux kernel, the following vulnerability has been resolved:
usb: typec: ucsi: validate connector number in ucsi_notify_common()
The connector number extracted from CCI via UCSI_CCI_CONNECTOR() is a
7-bit field (0-127) that is used to index into the connector array in
ucsi_connector_change(). However, the array is only allocated for the
number of connectors reported by the device (typically 2-4 entries).
A malicious or malfunctioning device could report an out-of-range
connector number in the CCI, causing an out-of-bounds array access in
ucsi_connector_change().
Add a bounds check in ucsi_notify_common(), the central point where CCI
is parsed after arriving from hardware, so that bogus connector numbers
are rejected before they propagate further.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-05-01
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_rndis: Fix net_device lifecycle with device_move
The net_device is allocated during function instance creation and
registered during the bind phase with the gadget device as its sysfs
parent. When the function unbinds, the parent device is destroyed, but
the net_device survives, resulting in dangling sysfs symlinks:
console:/ # ls -l /sys/class/net/usb0
lrwxrwxrwx ... /sys/class/net/usb0 ->
/sys/devices/platform/.../gadget.0/net/usb0
console:/ # ls -l /sys/devices/platform/.../gadget.0/net/usb0
ls: .../gadget.0/net/usb0: No such file or directory
Use device_move() to reparent the net_device between the gadget device
tree and /sys/devices/virtual across bind and unbind cycles. During the
final unbind, calling device_move(NULL) moves the net_device to the
virtual device tree before the gadget device is destroyed. On rebinding,
device_move() reparents the device back under the new gadget, ensuring
proper sysfs topology and power management ordering.
To maintain compatibility with legacy composite drivers (e.g., multi.c),
the borrowed_net flag is used to indicate whether the network device is
shared and pre-registered during the legacy driver's bind phase.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-01
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_subset: Fix net_device lifecycle with device_move
The net_device is allocated during function instance creation and
registered during the bind phase with the gadget device as its sysfs
parent. When the function unbinds, the parent device is destroyed, but
the net_device survives, resulting in dangling sysfs symlinks:
console:/ # ls -l /sys/class/net/usb0
lrwxrwxrwx ... /sys/class/net/usb0 ->
/sys/devices/platform/.../gadget.0/net/usb0
console:/ # ls -l /sys/devices/platform/.../gadget.0/net/usb0
ls: .../gadget.0/net/usb0: No such file or directory
Use device_move() to reparent the net_device between the gadget device
tree and /sys/devices/virtual across bind and unbind cycles. During the
final unbind, calling device_move(NULL) moves the net_device to the
virtual device tree before the gadget device is destroyed. On rebinding,
device_move() reparents the device back under the new gadget, ensuring
proper sysfs topology and power management ordering.
To maintain compatibility with legacy composite drivers (e.g., multi.c),
the bound flag is used to indicate whether the network device is shared
and pre-registered during the legacy driver's bind phase.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-01
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_eem: Fix net_device lifecycle with device_move
The net_device is allocated during function instance creation and
registered during the bind phase with the gadget device as its sysfs
parent. When the function unbinds, the parent device is destroyed, but
the net_device survives, resulting in dangling sysfs symlinks:
console:/ # ls -l /sys/class/net/usb0
lrwxrwxrwx ... /sys/class/net/usb0 ->
/sys/devices/platform/.../gadget.0/net/usb0
console:/ # ls -l /sys/devices/platform/.../gadget.0/net/usb0
ls: .../gadget.0/net/usb0: No such file or directory
Use device_move() to reparent the net_device between the gadget device
tree and /sys/devices/virtual across bind and unbind cycles. During the
final unbind, calling device_move(NULL) moves the net_device to the
virtual device tree before the gadget device is destroyed. On rebinding,
device_move() reparents the device back under the new gadget, ensuring
proper sysfs topology and power management ordering.
To maintain compatibility with legacy composite drivers (e.g., multi.c),
the bound flag is used to indicate whether the network device is shared
and pre-registered during the legacy driver's bind phase.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-01