In the Linux kernel, the following vulnerability has been resolved:
net: nfc: nci: Fix parameter validation for packet data
Since commit 9c328f54741b ("net: nfc: nci: Add parameter validation for
packet data") communication with nci nfc chips is not working any more.
The mentioned commit tries to fix access of uninitialized data, but
failed to understand that in some cases the data packet is of variable
length and can therefore not be compared to the maximum packet length
given by the sizeof(struct).
In the Linux kernel, the following vulnerability has been resolved:
mm/vmalloc: prevent RCU stalls in kasan_release_vmalloc_node
When CONFIG_PAGE_OWNER is enabled, freeing KASAN shadow pages during
vmalloc cleanup triggers expensive stack unwinding that acquires RCU read
locks. Processing a large purge_list without rescheduling can cause the
task to hold CPU for extended periods (10+ seconds), leading to RCU stalls
and potential OOM conditions.
The issue manifests in purge_vmap_node() -> kasan_release_vmalloc_node()
where iterating through hundreds or thousands of vmap_area entries and
freeing their associated shadow pages causes:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6229/1:b..l
...
task:kworker/0:17 state:R running task stack:28840 pid:6229
...
kasan_release_vmalloc_node+0x1ba/0xad0 mm/vmalloc.c:2299
purge_vmap_node+0x1ba/0xad0 mm/vmalloc.c:2299
Each call to kasan_release_vmalloc() can free many pages, and with
page_owner tracking, each free triggers save_stack() which performs stack
unwinding under RCU read lock. Without yielding, this creates an
unbounded RCU critical section.
Add periodic cond_resched() calls within the loop to allow:
- RCU grace periods to complete
- Other tasks to run
- Scheduler to preempt when needed
The fix uses need_resched() for immediate response under load, with a
batch count of 32 as a guaranteed upper bound to prevent worst-case stalls
even under light load.
In the Linux kernel, the following vulnerability has been resolved:
media: chips-media: wave5: Fix kthread worker destruction in polling mode
Fix the cleanup order in polling mode (irq < 0) to prevent kernel warnings
during module removal. Cancel the hrtimer before destroying the kthread
worker to ensure work queues are empty.
In polling mode, the driver uses hrtimer to periodically trigger
wave5_vpu_timer_callback() which queues work via kthread_queue_work().
The kthread_destroy_worker() function validates that both work queues
are empty with WARN_ON(!list_empty(&worker->work_list)) and
WARN_ON(!list_empty(&worker->delayed_work_list)).
The original code called kthread_destroy_worker() before hrtimer_cancel(),
creating a race condition where the timer could fire during worker
destruction and queue new work, triggering the WARN_ON.
This causes the following warning on every module unload in polling mode:
------------[ cut here ]------------
WARNING: CPU: 2 PID: 1034 at kernel/kthread.c:1430
kthread_destroy_worker+0x84/0x98
Modules linked in: wave5(-) rpmsg_ctrl rpmsg_char ...
Call trace:
kthread_destroy_worker+0x84/0x98
wave5_vpu_remove+0xc8/0xe0 [wave5]
platform_remove+0x30/0x58
...
---[ end trace 0000000000000000 ]---
In the Linux kernel, the following vulnerability has been resolved:
drm: renesas: rz-du: mipi_dsi: fix kernel panic when rebooting for some panels
Since commit 56de5e305d4b ("clk: renesas: r9a07g044: Add MSTOP for RZ/G2L")
we may get the following kernel panic, for some panels, when rebooting:
systemd-shutdown[1]: Rebooting.
Call trace:
...
do_serror+0x28/0x68
el1h_64_error_handler+0x34/0x50
el1h_64_error+0x6c/0x70
rzg2l_mipi_dsi_host_transfer+0x114/0x458 (P)
mipi_dsi_device_transfer+0x44/0x58
mipi_dsi_dcs_set_display_off_multi+0x9c/0xc4
ili9881c_unprepare+0x38/0x88
drm_panel_unprepare+0xbc/0x108
This happens for panels that need to send MIPI-DSI commands in their
unprepare() callback. Since the MIPI-DSI interface is stopped at that
point, rzg2l_mipi_dsi_host_transfer() triggers the kernel panic.
Fix by moving rzg2l_mipi_dsi_stop() to new callback function
rzg2l_mipi_dsi_atomic_post_disable().
With this change we now have the correct power-down/stop sequence:
systemd-shutdown[1]: Rebooting.
rzg2l-mipi-dsi 10850000.dsi: rzg2l_mipi_dsi_atomic_disable(): entry
ili9881c-dsi 10850000.dsi.0: ili9881c_unprepare(): entry
rzg2l-mipi-dsi 10850000.dsi: rzg2l_mipi_dsi_atomic_post_disable(): entry
reboot: Restarting system
In the Linux kernel, the following vulnerability has been resolved:
rapidio: replace rio_free_net() with kfree() in rio_scan_alloc_net()
When idtab allocation fails, net is not registered with rio_add_net() yet,
so kfree(net) is sufficient to release the memory. Set mport->net to NULL
to avoid dangling pointer.
In the Linux kernel, the following vulnerability has been resolved:
octeontx2-af: Workaround SQM/PSE stalls by disabling sticky
NIX SQ manager sticky mode is known to cause stalls when multiple SQs
share an SMQ and transmit concurrently. Additionally, PSE may deadlock
on transitions between sticky and non-sticky transmissions. There is
also a credit drop issue observed when certain condition clocks are
gated.
work around these hardware errata by:
- Disabling SQM sticky operation:
- Clear TM6 (bit 15)
- Clear TM11 (bit 14)
- Disabling sticky → non-sticky transition path that can deadlock PSE:
- Clear TM5 (bit 23)
- Preventing credit drops by keeping the control-flow clock enabled:
- Set TM9 (bit 21)
These changes are applied via NIX_AF_SQM_DBG_CTL_STATUS. With this
configuration the SQM/PSE maintain forward progress under load without
credit loss, at the cost of disabling sticky optimizations.
In the Linux kernel, the following vulnerability has been resolved:
media: rockchip: rga: Fix possible ERR_PTR dereference in rga_buf_init()
rga_get_frame() can return ERR_PTR(-EINVAL) when buffer type is
unsupported or invalid. rga_buf_init() does not check the return value
and unconditionally dereferences the pointer when accessing f->size.
Add proper ERR_PTR checking and return the error to prevent
dereferencing an invalid pointer.
In the Linux kernel, the following vulnerability has been resolved:
mm/slab: do not access current->mems_allowed_seq if !allow_spin
Lockdep complains when get_from_any_partial() is called in an NMI
context, because current->mems_allowed_seq is seqcount_spinlock_t and
not NMI-safe:
================================
WARNING: inconsistent lock state
6.19.0-rc5-kfree-rcu+ #315 Tainted: G N
--------------------------------
inconsistent {INITIAL USE} -> {IN-NMI} usage.
kunit_try_catch/9989 [HC1[1]:SC0[0]:HE0:SE1] takes:
ffff889085799820 (&____s->seqcount#3){.-.-}-{0:0}, at: ___slab_alloc+0x58f/0xc00
{INITIAL USE} state was registered at:
lock_acquire+0x185/0x320
kernel_init_freeable+0x391/0x1150
kernel_init+0x1f/0x220
ret_from_fork+0x736/0x8f0
ret_from_fork_asm+0x1a/0x30
irq event stamp: 56
hardirqs last enabled at (55): [<ffffffff850a68d7>] _raw_spin_unlock_irq+0x27/0x70
hardirqs last disabled at (56): [<ffffffff850858ca>] __schedule+0x2a8a/0x6630
softirqs last enabled at (0): [<ffffffff81536711>] copy_process+0x1dc1/0x6a10
softirqs last disabled at (0): [<0000000000000000>] 0x0
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&____s->seqcount#3);
<Interrupt>
lock(&____s->seqcount#3);
*** DEADLOCK ***
According to Documentation/locking/seqlock.rst, seqcount_t is not
NMI-safe and seqcount_latch_t should be used when read path can interrupt
the write-side critical section. In this case, do not access
current->mems_allowed_seq and avoid retry.
In the Linux kernel, the following vulnerability has been resolved:
mm/hugetlb: restore failed global reservations to subpool
Commit a833a693a490 ("mm: hugetlb: fix incorrect fallback for subpool")
fixed an underflow error for hstate->resv_huge_pages caused by incorrectly
attributing globally requested pages to the subpool's reservation.
Unfortunately, this fix also introduced the opposite problem, which would
leave spool->used_hpages elevated if the globally requested pages could
not be acquired. This is because while a subpool's reserve pages only
accounts for what is requested and allocated from the subpool, its "used"
counter keeps track of what is consumed in total, both from the subpool
and globally. Thus, we need to adjust spool->used_hpages in the other
direction, and make sure that globally requested pages are uncharged from
the subpool's used counter.
Each failed allocation attempt increments the used_hpages counter by how
many pages were requested from the global pool. Ultimately, this renders
the subpool unusable, as used_hpages approaches the max limit.
The issue can be reproduced as follows:
1. Allocate 4 hugetlb pages
2. Create a hugetlb mount with max=4, min=2
3. Consume 2 pages globally
4. Request 3 pages from the subpool (2 from subpool + 1 from global)
4.1 hugepage_subpool_get_pages(spool, 3) succeeds.
used_hpages += 3
4.2 hugetlb_acct_memory(h, 1) fails: no global pages left
used_hpages -= 2
5. Subpool now has used_hpages = 1, despite not being able to
successfully allocate any hugepages. It believes it can now only
allocate 3 more hugepages, not 4.
With each failed allocation attempt incrementing the used counter, the
subpool eventually reaches a point where its used counter equals its
max counter. At that point, any future allocations that try to
allocate hugeTLB pages from the subpool will fail, despite the subpool
not having any of its hugeTLB pages consumed by any user.
Once this happens, there is no way to make the subpool usable again,
since there is no way to decrement the used counter as no process is
really consuming the hugeTLB pages.
The underflow issue that the original commit fixes still remains fixed
as well.
Without this fix, used_hpages would keep on leaking if
hugetlb_acct_memory() fails.