Linux: >> Linux Kernel >> 6.16.2 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: mld: stop TX during firmware restart
When iwlwifi firmware crashes (e.g., NMI_INTERRUPT_UNKNOWN on Intel
BE201/Wi-Fi 7), iwl_mld_nic_error() sets mld->fw_status.in_hw_restart
to true. However, iwl_mld_tx_from_txq() does not check this flag before
dequeuing frames from mac80211 and pushing them to the transport layer.
Since the firmware is dead, iwl_trans_tx() returns -EIO for each frame,
which then gets freed immediately. Under high-throughput conditions
(e.g., Tailscale UDP traffic or active SSH sessions), this creates a
tight dequeue-send-fail-free loop that wastes CPU cycles and generates
rapid skb allocation churn, leading to memory pressure from slab
fragmentation.
The RX path already has this guard (iwl_mld_rx_mpdu checks
in_hw_restart at rx.c:1906), and so does the TXQ allocation worker
(iwl_mld_add_txqs_wk at tx.c:156). Add the same guard to
iwl_mld_tx_from_txq() to stop all TX during firmware restart.
Frames left in mac80211's TXQs are naturally drained after restart
completes, when queue reallocation triggers iwl_mld_tx_from_txq()
via iwl_mld_add_txq_list(), or when new upper-layer traffic invokes
wake_tx_queue.
Tested on ASUS Zenbook 14 UX3405CA with Intel BE201 (Wi-Fi 7) on
kernel 6.19.5 where the firmware crashes approximately every 10-15
minutes under Tailscale traffic.
CVSS Score
7.5
EPSS Score
0.003
Published
2026-07-19
In the Linux kernel, the following vulnerability has been resolved:
phonet/pep: disable BH around forwarded sk_receive_skb()
The networking receive path is usually run from softirq context, but
protocols that take the socket lock may have packets stored in the
backlog and processed later from process context. In that case
release_sock() -> __release_sock() drops the slock with spin_unlock_bh()
and then calls sk->sk_backlog_rcv() with bottom halves enabled.
Typical sk_backlog_rcv handlers process the socket whose backlog is
being drained, so the BH state at entry is irrelevant for the slocks
they touch. pep_do_rcv() is different: when the inbound skb targets an
existing PEP pipe, it forwards the skb to a different *child* socket
via sk_receive_skb(). That helper takes the child slock with
bh_lock_sock_nested(), which is just spin_lock_nested() and assumes BH
is already off. The same child slock therefore ends up acquired with
BH on (process path) and with BH off (softirq path):
process context softirq context
--------------- ---------------
release_sock(listener) __netif_receive_skb()
__release_sock() phonet_rcv()
spin_unlock_bh() __sk_receive_skb(listener)
[BH now ENABLED] [BH already disabled]
sk_backlog_rcv: sk_backlog_rcv:
pep_do_rcv() pep_do_rcv()
sk_receive_skb(child) sk_receive_skb(child)
bh_lock_sock_nested(child) bh_lock_sock_nested(child)
=> SOFTIRQ-ON-W => IN-SOFTIRQ-W
Lockdep flags this as inconsistent lock state, and it can become a real
self-deadlock if a softirq on the same CPU tries to receive to the same
child socket while its slock is held in the BH-enabled path:
WARNING: inconsistent lock state
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
(slock-AF_PHONET/1){+.?.}-{3:3}, at: __sk_receive_skb+0x1cf/0x900
__sk_receive_skb net/core/sock.c:563
sk_receive_skb include/net/sock.h:2022 [inline]
pep_do_rcv net/phonet/pep.c:675
sk_backlog_rcv include/net/sock.h:1190
__release_sock net/core/sock.c:3216
release_sock net/core/sock.c:3815
pep_sock_accept net/phonet/pep.c:879
Wrap the forwarded sk_receive_skb() in local_bh_disable() /
local_bh_enable() so the child slock is always acquired with BH off.
local_bh_disable() nests safely on the softirq path.
Discovered via in-house syzkaller fuzzing; the same root cause also
on the linux-6.1.y syzbot dashboard as extid 44f0626dd6284f02663c.
Reproduced under KASAN + LOCKDEP + PROVE_LOCKING, reproducer:
https://pastebin.com/A3t8xzCR
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-19
In the Linux kernel, the following vulnerability has been resolved:
idpf: fix read_dev_clk_lock spinlock init in idpf_ptp_init()
In idpf_ptp_init(), read_dev_clk_lock is initialized after
ptp_schedule_worker() had already been called (and after
idpf_ptp_settime64() could reach the lock). The PTP aux worker
fires immediately upon scheduling and can call into
idpf_ptp_read_src_clk_reg_direct(), which takes
spin_lock(&ptp->read_dev_clk_lock) on an uninitialized lock, triggering
the lockdep "non-static key" warning:
[12973.796587] idpf 0000:83:00.0: Device HW Reset initiated
[12974.094507] INFO: trying to register non-static key.
...
[12974.097208] Call Trace:
[12974.097213] <TASK>
[12974.097218] dump_stack_lvl+0x93/0xe0
[12974.097234] register_lock_class+0x4c4/0x4e0
[12974.097249] ? __lock_acquire+0x427/0x2290
[12974.097259] __lock_acquire+0x98/0x2290
[12974.097272] lock_acquire+0xc6/0x310
[12974.097281] ? idpf_ptp_read_src_clk_reg+0xb7/0x150 [idpf]
[12974.097311] ? lockdep_hardirqs_on_prepare+0xde/0x190
[12974.097318] ? finish_task_switch.isra.0+0xd2/0x350
[12974.097330] ? __pfx_ptp_aux_kworker+0x10/0x10 [ptp]
[12974.097343] _raw_spin_lock+0x30/0x40
[12974.097353] ? idpf_ptp_read_src_clk_reg+0xb7/0x150 [idpf]
[12974.097373] idpf_ptp_read_src_clk_reg+0xb7/0x150 [idpf]
[12974.097391] ? kthread_worker_fn+0x88/0x3d0
[12974.097404] ? kthread_worker_fn+0x4e/0x3d0
[12974.097411] idpf_ptp_update_cached_phctime+0x26/0x120 [idpf]
[12974.097428] ? _raw_spin_unlock_irq+0x28/0x50
[12974.097436] idpf_ptp_do_aux_work+0x15/0x20 [idpf]
[12974.097454] ptp_aux_kworker+0x20/0x40 [ptp]
[12974.097464] kthread_worker_fn+0xd5/0x3d0
[12974.097474] ? __pfx_kthread_worker_fn+0x10/0x10
[12974.097482] kthread+0xf4/0x130
[12974.097489] ? __pfx_kthread+0x10/0x10
[12974.097498] ret_from_fork+0x32c/0x410
[12974.097512] ? __pfx_kthread+0x10/0x10
[12974.097519] ret_from_fork_asm+0x1a/0x30
[12974.097540] </TASK>
Move the call to spin_lock_init() up a bit to make sure read_dev_clk_lock
is not touched before it's been initialized.
CVSS Score
9.8
EPSS Score
0.003
Published
2026-07-19
In the Linux kernel, the following vulnerability has been resolved:
test_kprobes: clear kprobes between test runs
Running the kprobes sanity tests twice makes all tests fail and
eventually crashes the kernel.
[root@martin-riscv-1 ~]# echo 1 > /sys/kernel/debug/kunit/kprobes_test/run
...
# Totals: pass:5 fail:0 skip:0 total:5
ok 1 kprobes_test
[root@martin-riscv-1 ~]# echo 1 > /sys/kernel/debug/kunit/kprobes_test/run
...
# test_kprobe: EXPECTATION FAILED at lib/tests/test_kprobes.c:64
Expected 0 == register_kprobe(&kp), but
register_kprobe(&kp) == -22 (0xffffffffffffffea)
...
Unable to handle kernel paging request ...
The testsuite defines several kprobes and kretprobes as static variables
that are preserved across test runs.
After register_kprobe and unregister_kprobe, a kprobe contains some
leftover data that must be cleared before the kprobe can be registered
again. The tests are setting symbol_name to define the probe location.
Address and flags must be cleared.
The existing code clears some of the probes between subsequent tests, but
not between two test runs. The leftover data from a previous test run
makes the registrations fail in the next run.
Move the cleanups for all kprobes into kprobes_test_init, this function
is called before each single test (including the first test of a test
run).
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-19
In the Linux kernel, the following vulnerability has been resolved:
ARM: integrator: Fix early initialization
Starting with commit bdb249fce9ad4 ("ARM: integrator: read counter using
syscon/regmap"), intcp_init_early calls syscon_regmap_lookup_by_compatible
which in turn calls of_syscon_register. This function allocates memory.
Since the memory management code has not been initialized at that time,
the call always fails. It either returns -ENOMEM or crashes as follows.
Unable to handle kernel NULL pointer dereference at virtual address 0000000c when read
[0000000c] *pgd=00000000
Internal error: Oops: 5 [#1] ARM
Modules linked in:
CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.15.0-rc5-00026-g5fcc9bf84ee5 #1 PREEMPT
Hardware name: ARM Integrator/CP (Device Tree)
PC is at __kmalloc_cache_noprof+0xec/0x39c
LR is at __kmalloc_cache_noprof+0x34/0x39c
...
Call trace:
__kmalloc_cache_noprof from of_syscon_register+0x7c/0x310
of_syscon_register from device_node_get_regmap+0xa4/0xb0
device_node_get_regmap from intcp_init_early+0xc/0x40
intcp_init_early from start_kernel+0x60/0x688
start_kernel from 0x0
The crash is seen due to a dereferenced pointer which is not supposed to be
NULL but is NULL if the memory management subsystem has not been
initialized. The crash is not seen with all versions of gcc. Some versions
such as gcc 9.x apparently do not dereference the pointer, presumably if
tracing is disabled. The problem has been reproduced with gcc 10.x, 11.x,
and 13.x. Either case, if the crash is not seen, the call to
syscon_regmap_lookup_by_compatible returns -ENOMEM, and
sched_clock_register is never called.
Fix the problem by moving the early initialization code into the standard
machine initialization code.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-19
In the Linux kernel, the following vulnerability has been resolved:
firmware: arm_ffa: Check for NULL FF-A ID table while driver registration
The bus match callback assumes that every FF-A driver provides an
id_table and dereferences it unconditionally. Enforce that contract at
registration time so a buggy client driver cannot crash the bus during
match.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-19
In the Linux kernel, the following vulnerability has been resolved:
spi: sprd: fix error pointer deref after DMA setup failure
The driver falls back to PIO mode if DMA setup fails during probe.
Make sure to check the dma.enabled flag before trying to release the DMA
channels also on late probe errors to avoid dereferencing an error
pointer (or attempting to release a channel a second time).
This issue was flagged by Sashiko when reviewing a devres allocation
conversion patch.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-19
In the Linux kernel, the following vulnerability has been resolved:
netfs, afs: Fix write skipping in dir/link writepages
Fix netfs_write_single() and afs_single_writepages() to better handle a
write that would be skipped due to lock contention and WB_SYNC_NONE by
returning 1 from netfs_write_single() if it skipped and making
afs_single_writepages() skip also. If a skip occurs, the inode must be
re-marked as the VFS may have cleared the mark.
This is really only theoretical for directories in netfs_write_single() as
the only path to that is through afs_single_writepages() that takes the
->validate_lock around it, thereby serialising it.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-19
In the Linux kernel, the following vulnerability has been resolved:
drm/msm: Fix iommu_map_sgtable() return value check and avoid WARN
Commit "iommu: return full error code from iommu_map_sg[_atomic]()"
changed iommu_map_sgtable() to return an ssize_t and negative values
in error cases, rather than a size_t and a zero.
Store the return value in the appropriate type and in case of error,
return it rather than WARNing.
Patchwork: https://patchwork.freedesktop.org/patch/719685/
CVSS Score
8.8
EPSS Score
0.001
Published
2026-07-19
In the Linux kernel, the following vulnerability has been resolved:
drm/msm/adreno: Fix a reference leak in a6xx_gpu_init()
In a6xx_gpu_init(), node is obtained via of_parse_phandle().
While there was a manual of_node_put() at the end of the
common path, several early error returns would bypass this call,
resulting in a reference leak.
Fix this by using the __free(device_node) cleanup handler to
release the reference when the variable goes out of scope.
Patchwork: https://patchwork.freedesktop.org/patch/700661/
CVSS Score
5.5
EPSS Score
0.002
Published
2026-07-19