Linux: >> Linux Kernel >> 6.18.9 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix out-of-bounds read in dp_get_eq_aux_rd_interval()
[Why & How]
The aux_rd_interval array in struct dc_lttpr_caps is declared with
MAX_REPEATER_CNT - 1 (7) elements, indexed 0..6. However, the offset
parameter passed to dp_get_eq_aux_rd_interval() can be as large as
MAX_REPEATER_CNT (8) when a sink reports 8 LTTPR repeaters via DPCD.
This leads to an out-of-bounds read of aux_rd_interval[7] when offset
is 8.
Fix this by growing aux_rd_interval to MAX_REPEATER_CNT elements to
accommodate the full range of valid repeater counts defined by the DP
spec.
(cherry picked from commit a55a458a8df37a65ffda5cf721d554a8f74f6b04)
CVSS Score
7.1
EPSS Score
0.001
Published
2026-07-01
In the Linux kernel, the following vulnerability has been resolved:
slimbus: qcom-ngd-ctrl: Avoid ABBA on tx_lock/ctrl->lock
During the SSR/PDR down notification the tx_lock is taken with the
intent to provide synchronization with active DMA transfers.
But during this period qcom_slim_ngd_down() is invoked, which ends up in
slim_report_absent(), which takes the slim_controller lock. In multiple
other codepaths these two locks are taken in the opposite order (i.e.
slim_controller then tx_lock).
The result is a lockdep splat, and a possible deadlock:
rprocctl/449 is trying to acquire lock:
ffff00009793e620 (&ctrl->lock){+.+.}-{4:4}, at: slim_report_absent (drivers/slimbus/core.c:322) slimbus
but task is already holding lock:
ffff00009793fb50 (&ctrl->tx_lock){+.+.}-{4:4}, at: qcom_slim_ngd_ssr_pdr_notify (drivers/slimbus/qcom-ngd-ctrl.c:1475) slim_qcom_ngd_ctrl
which lock already depends on the new lock.
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&ctrl->tx_lock);
lock(&ctrl->lock);
lock(&ctrl->tx_lock);
lock(&ctrl->lock);
The assumption is that the comment refers to the desire to not call
qcom_slim_ngd_exit_dma() while we have an ongoing DMA TX transaction.
But any such transaction is initiated and completed within a single
qcom_slim_ngd_xfer_msg().
Prior to calling qcom_slim_ngd_exit_dma() the slim_controller is torn
down, all child devices are notified that the slimbus is gone and the
child devices are removed.
Stop taking the tx_lock in qcom_slim_ngd_ssr_pdr_notify() to avoid the
deadlock.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-01
In the Linux kernel, the following vulnerability has been resolved:
agp/amd64: Fix broken error propagation in agp_amd64_probe()
A NULL pointer dereference was observed in the AMD64 AGP driver when
running in a virtualized environment (e.g. qemu/kvm) without a physical
AMD northbridge. The crash occurs in amd64_fetch_size() when attempting
to dereference the pointer returned by node_to_amd_nb(0).
The root cause of this crash is broken error propagation in
agp_amd64_probe(): When no AMD northbridges are found, cache_nbs()
correctly returns -ENODEV. However, the probe function erroneously
checks the return value against exactly -1, rather than < 0.
As a result, the hardware absence error is masked, allowing the driver
to improperly proceed with initialization. It eventually calls
agp_add_bridge(), which invokes amd64_fetch_size(). Since the hardware
does not exist, node_to_amd_nb(0) returns NULL, leading to a General
Protection Fault (GPF) when accessing its ->misc member.
Fix the issue by correcting the error check in agp_amd64_probe() to
abort properly when cache_nbs() returns any negative error code. This
prevents the driver from erroneously proceeding without hardware, thereby
avoiding the subsequent NULL pointer dereference at its source.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-29
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7921: Place upper limit on station AID
Any station configured with an AID over 20 causes a firmware crash.
This situation occurred in our testing using an AP interface on 7922
hardware, with a modified hostapd, sourced from Mediatek's OpenWRT
feeds.
In stock hostapd, station AIDs begin counting at 1, and this
configuration is prevented with an upper limit on associated stations.
However, the modified hostapd began allocation at 65, which caused the
firmware to crash. This fix does not allow these AIDs to work, but will
prevent the firmware crash.
This crash was only seen on IFTYPE_AP interfaces, and the fix does not
appear to have an effect on IFTYPE_STATION behavior.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-26
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7925: prevent NULL pointer dereference in mt7925_tx_check_aggr()
Move the NULL check for 'sta' before dereferencing it to prevent a
possible crash.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-26
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: reject zero bd_oblocknr in nilfs_ioctl_mark_blocks_dirty()
nilfs_ioctl_mark_blocks_dirty() uses bd_oblocknr to detect dead blocks
by comparing it with the current block number bd_blocknr. If they differ,
the block is considered dead and skipped.
However, bd_oblocknr should never be 0 since block 0 typically stores the
primary superblock and is never a valid GC target block. A corrupted ioctl
request with bd_oblocknr set to 0 causes the comparison to incorrectly
match when the lookup returns -ENOENT and sets bd_blocknr to 0, bypassing
the dead block check and calling nilfs_bmap_mark() on a non-existent
block. This causes nilfs_btree_do_lookup() to return -ENOENT, triggering
the WARN_ON(ret == -ENOENT).
Fix this by rejecting ioctl requests with bd_oblocknr set to 0 at the
beginning of each iteration.
[ryusuke: slightly modified the commit message and comments for accuracy]
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-26
In the Linux kernel, the following vulnerability has been resolved:
io_uring/napi: cap busy_poll_to 10 msec
Currently there's no cap on the maximum amount of time that napi is
allowed to poll if no events are found, which can lead to kernel
complaints on a task being stuck as there's no conditional rescheduling
done within that loop.
Just cap it to 10 msec in total, that's already way above any kind of
sane value that will reap any benefits, yet low enough that it's
nowhere near being able to trigger preemption complaints.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-26
In the Linux kernel, the following vulnerability has been resolved:
net: dsa: remove redundant netdev_lock_ops() from conduit ethtool ops
DSA replaces the conduit (master) device's ethtool_ops with its own
wrappers that aggregate stats from both the conduit and DSA switch
ports. Taking the lock again inside the DSA wrappers causes a deadlock.
Stumbled upon this when booting qemu with fbnic and CONFIG_NET_DSA_LOOP=y
(which looks like some kind of testing device that auto-populates the ports
of eth0). `ethtool -i` is enough to deadlock. This means we have basically zero
coverage for DSA stuff with real ops locked devs.
Remove the redundant netdev_lock_ops()/netdev_unlock_ops() calls from
the DSA conduit ethtool wrappers.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-26
In the Linux kernel, the following vulnerability has been resolved:
net: mana: Use pci_name() for debugfs directory naming
Use pci_name(pdev) for the per-device debugfs directory instead of
hardcoded "0" for PFs and pci_slot_name(pdev->slot) for VFs. The
previous approach had two issues:
1. pci_slot_name() dereferences pdev->slot, which can be NULL for VFs
in environments like generic VFIO passthrough or nested KVM,
causing a NULL pointer dereference.
2. Multiple PFs would all use "0", and VFs across different PCI
domains or buses could share the same slot name, leading to
-EEXIST errors from debugfs_create_dir().
pci_name(pdev) returns the unique BDF address, is always valid, and is
unique across the system.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-26
In the Linux kernel, the following vulnerability has been resolved:
pinctrl: pinconf-generic: Fully validate 'pinmux' property
The pinconf_generic_parse_dt_pinmux() assumes that the 'pinmux' property
is not empty when present. This might be not true. With that, the allocator
will give a special value in return and not NULL which lead to the crash
when trying to access that (invalid) memory. Fix that by fully validating
'pinmux' value, including its length.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-26