Linux: >> Linux Kernel >> 6.18.34 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
arm64: errata: Mitigate TLBI errata on various Arm CPUs
A number of CPUs developed by Arm suffer from errata whereby a broadcast
TLBI;DSB sequence may complete before the global observation of writes
which are translated by an affected TLB entry.
These errata ONLY affect the completion of memory accesses which have
been translated by an invalidated TLB entry, and these errata DO NOT
affect the actual invalidation of TLB entries. TLB entries are removed
correctly.
This issue has been assigned CVE ID CVE-2025-10263.
To mitigate this issue, Arm recommends that software follows any
affected TLBI;DSB sequence with an additional TLBI;DSB, which will
ensure that all memory write effects affected by the first TLBI have
been globally observed. The additional TLBI can use any operation that
is broadcast to affected CPUs, and the additional DSB can use any option
that is sufficient to complete the additional TLBI.
The ARM64_WORKAROUND_REPEAT_TLBI workaround is sufficient to mitigate
the issue. Enable this workaround for affected CPUs, and update the
silicon errata documentation accordingly.
Note that due to the manner in which Arm develops IP and tracks errata,
some CPUs share a common erratum number.
CVSS Score
8.8
EPSS Score
0.001
Published
2026-07-01
In the Linux kernel, the following vulnerability has been resolved:
net: rds: clear i_sends on setup unwind
The RDS IB connection teardown path is written so it can run during
partial startup and on repeated shutdown attempts. It uses NULL
pointers to distinguish resources that are still owned from resources
that have already been released.
When rds_ib_setup_qp() fails after allocating i_sends but before
allocating i_recvs, the sends_out path frees i_sends without clearing
the pointer. A later shutdown pass can still treat that stale pointer
as a live send ring allocation.
Clear i_sends after vfree() in the error unwind path so the existing
shutdown logic continues to use the correct ownership state.
CVSS Score
9.8
EPSS Score
0.004
Published
2026-07-01
In the Linux kernel, the following vulnerability has been resolved:
i2c: imx: fix clock and pinctrl state inconsistency in runtime PM
In i2c_imx_runtime_suspend(), the clock is disabled before switching
the pinctrl state to sleep. If pinctrl_pm_select_sleep_state() fails,
the runtime suspend is aborted but the clock remains disabled, causing
a system crash when the hardware is subsequently accessed.
Fix this by switching the pinctrl state before disabling the clock so
that a pinctrl failure leaves the clock enabled and the hardware
accessible.
In i2c_imx_runtime_resume(), restore the pinctrl state back to sleep
if clk_enable() fails to keep the consistent.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-01
In the Linux kernel, the following vulnerability has been resolved:
fhandle: fix UAF due to unlocked ->mnt_ns read in may_decode_fh()
may_decode_fh() accesses mount::mnt_ns without holding any locks; that
means the mount can concurrently be unmounted, and the mnt_namespace can
concurrently be freed after an RCU grace period.
This race can happens as follows, assuming that the mount point was
created by open_tree(..., OPEN_TREE_CLONE):
thread 1 thread 2 RCU
__do_sys_open_by_handle_at
do_handle_open
handle_to_path
may_decode_fh
is_mounted
[mount::mnt_ns access]
[mount::mnt_ns access]
__do_sys_close
fput_close_sync
__fput
dissolve_on_fput
umount_tree
class_namespace_excl_destructor
namespace_unlock
free_mnt_ns
mnt_ns_tree_remove
call_rcu(mnt_ns_release_rcu)
mnt_ns_release_rcu
mnt_ns_release
kfree
[mnt_namespace::user_ns access] **UAF**
Fix it by taking rcu_read_lock() around the mount::mnt_ns access, like
in __prepend_path().
Additionally, document the semantics of mount::mnt_ns, and use WRITE_ONCE()
for writers that can race with lockless readers.
This bug is unreachable unless one of the following is set:
- CONFIG_PREEMPTION
- CONFIG_RCU_STRICT_GRACE_PERIOD
because it requires an RCU grace period to happen during a syscall without
an explicit preemption.
This doesn't seem to have interesting security impact; worst-case, it could
leak the result of an integer comparison to userspace (from the level
check in cap_capable()), cause an endless loop, or crash the kernel by
dereferencing an invalid address.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-07-01
In the Linux kernel, the following vulnerability has been resolved:
arm64: mm: call pagetable dtor when freeing hot-removed page tables
Since 5e8eb9aeeda3 ("arm64: mm: always call PTE/PMD ctor in
__create_pgd_mapping()") page-table allocation on ARM64 always calls
pagetable_{pte,pmd,pud,p4d}_ctor(). This sets the page_type to
PGTY_table, increments NR_PAGETABLE and possible allocates a PTL. However
the matching pagetable_dtor() calls were never added.
With DEBUG_VM enabled on kernel versions prior to v6.17 without
2dfcd1608f3a9 ("mm/page_alloc: let page freeing clear any set page type")
this leads to the following warning when freeing these pages due to
page->page_type sharing page->_mapcount:
BUG: Bad page state in process ... pfn:284fbb
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x284fbb
flags: 0x17fffc000000000(node=0|zone=2|lastcpupid=0x1ffff)
page_type: f2(table)
page dumped because: nonzero mapcount
Call trace:
bad_page+0x13c/0x160
__free_frozen_pages+0x6cc/0x860
___free_pages+0xf4/0x180
free_pages+0x54/0x80
free_hotplug_page_range.part.0+0x58/0x90
free_empty_tables+0x438/0x500
__remove_pgd_mapping.constprop.0+0x60/0xa8
arch_remove_memory+0x48/0x80
try_remove_memory+0x158/0x1d8
offline_and_remove_memory+0x138/0x180
It can also lead to leaking the ptl allocation if ALLOC_SPLIT_PTLOCKS is
defined and incorrect NR_PAGETABLE stats. Fix this by calling
pagetable_dtor() in free_hotplug_pgtable_page() prior to freeing the page
to undo the effects of calling pagetable_*_ctor().
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-01
In the Linux kernel, the following vulnerability has been resolved:
ARM: 9475/1: entry: use byte load for KASAN VMAP stack shadow
Commit 44e9a3bb76e5 ("ARM: 9430/1: entry: Do a dummy read from
VMAP shadow") added a dummy read from the KASAN VMAP stack shadow in
__switch_to(). The read uses ldr, but the KASAN shadow address is
byte-granular and is not guaranteed to be word aligned.
ARMv5 faults unaligned word loads. With CONFIG_KASAN_VMALLOC and
CONFIG_VMAP_STACK enabled, ARM926/VersatilePB crashes in __switch_to()
with an alignment exception before reaching init.
Use ldrb for the dummy shadow access. The code only needs to fault in the
shadow mapping if the stack shadow is missing, so a byte load is sufficient
and matches the granularity of KASAN shadow memory.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-01
In the Linux kernel, the following vulnerability has been resolved:
KVM: Don't WARN if memory is dirtied without a vCPU when the VM is dying
When marking a page dirty, complain about not having a running/loaded vCPU
if and only if the VM is still alive, i.e. its refcount is non-zero. This
will allow fixing a memory leak for x86 SEV-ES guests without hitting what
is effectively a false positive on the WARN.
For some SEV-ES VM-Exits, KVM keeps a writable mapping of a guest page
across an exit to userspace, and typically unmaps the page on the next
KVM_RUN. But if userspace never calls KVM_RUN after such an exit, then KVM
needs to unmap the page when the vCPU is destroyed, which in turn triggers
the WARN about not having a running vCPU.
Alternatively, SEV-ES could temporarily load the vCPU to suppress the WARN,
as is done in nested_vmx_free_vcpu() (but for completely unrelated reasons;
suppressing WARN from nested_put_vmcs12_pages() is pure happenstance). But
loading a vCPU during destruction is gross (ideally nVMX code would be
cleaned up), risks complicating the SEV-ES code (KVM would need to ensure
the temporarily load()+put() only runs when the vCPU isn't already loaded),
and is ultimately pointless.
The motivation for the WARN is to guard against KVM dirtying guest memory
without pushing the corresponding GFN to the active vCPU's dirty ring, e.g.
to ensure userspace doesn't miss a dirty page. But for the VM's refcount
to reach zero, there can't be _any_ userspace mappings to the dirty ring,
as mapping the dirty ring requires doing mmap() on the vCPU FD. I.e. if
userspace had a valid mapping for the dirty ring, then the vCPU file and
thus the owning VM would still be alive. And so since userspace can't
possibly reach the dirty ring, whether or not KVM technically "misses" a
push to the dirty ring is irrelevant.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-01
In the Linux kernel, the following vulnerability has been resolved:
rust: arm64: set uwtable llvm module flag for CONFIG_UNWIND_TABLES
Due to a rustc bug [1] the -Cforce-unwind-tables=y flag only emits the
uwtable annotation for functions, but not for the module. This means
that compiler-generated functions such as 'asan.module_ctor' do not
receive the uwtable annotation.
When CONFIG_UNWIND_PATCH_PAC_INTO_SCS is enabled, this leads to boot
failures because the dwarf information emitted for the kasan
constructors is wrong, which causes the SCS boot patching code to
patch the constructor in an illegal manner. Specifically, the paciasp
instruction is patched, but the autiasp instruction is not. This
mismatch leads to a crash when the constructor is called during boot.
==================================================================
BUG: KASAN: global-out-of-bounds in do_basic_setup+0x4c/0x90
Read of size 8 at addr ffffffe3cc7eb488 by task swapper/0/1
Specifically the faulting instruction is the (*fn)() to invoke the
constructor in do_ctors() of the init/main.c file.
Once the fix lands in rustc, this flag can be made conditional on the
rustc version. Note that passing the flag on a rustc with the fix
present has no effect.
[ The fix [1] has landed for Rust 1.98.0 (expected release on
2026-08-20).
Thus add a version check as discussed.
- Miguel ]
[ Adjusted link and comment. - Miguel ]
CVSS Score
7.1
EPSS Score
0.001
Published
2026-07-01
In the Linux kernel, the following vulnerability has been resolved:
drm/virtio: Fix driver removal with disabled KMS
DRM atomic and modesetting aren't initialized if virtio-gpu driver built
with disabled KMS, leading to access of uninitialized data on driver
removal/unbinding and crashing kernel. Fix it by skipping shutting down
atomic core with unavailable KMS.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-01
In the Linux kernel, the following vulnerability has been resolved:
slimbus: qcom-ngd-ctrl: Register callbacks after creating the ngd
When the remoteproc starts in parallel with the NGD driver being probed,
or the remoteproc is already up when the PDR lookup is being registered,
or in the theoretical event that we get an interrupt from the hardware,
these callbacks will operate on uninitialized data. This result in
issues to boot the affected boards.
One such example can be seen in the following fault, where
qcom_slim_ngd_ssr_pdr_notify() schedules work on the NULL ngd_up_work.
[ 21.858578] ------------[ cut here ]------------
[ 21.858745] WARNING: kernel/workqueue.c:2338 at __queue_work+0x5e0/0x790, CPU#2: kworker/2:2/116
...
[ 21.859251] Call trace:
[ 21.859255] __queue_work+0x5e0/0x790 (P)
[ 21.859265] queue_work_on+0x6c/0xf0
[ 21.859273] qcom_slim_ngd_ssr_pdr_notify+0x110/0x150 [slim_qcom_ngd_ctrl]
[ 21.859304] qcom_slim_ngd_ssr_notify+0x24/0x40 [slim_qcom_ngd_ctrl]
[ 21.859318] notifier_call_chain+0xa4/0x230
[ 21.859329] srcu_notifier_call_chain+0x64/0xb8
[ 21.859338] ssr_notify_start+0x40/0x78 [qcom_common]
[ 21.859355] rproc_start+0x130/0x230
[ 21.859367] rproc_boot+0x3d4/0x518
...
Move the enablement of interrupts, and the registration of SSR and PDR
until after the NGD device has been registered.
This could be further refined by moving initialization to the control
driver probe and by removing the platform driver model from the picture.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-07-01