Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
drm/bridge: samsung-dsim: Fix memory leak in error path
In samsung_dsim_host_attach(), drm_bridge_add() is called to add the
bridge. However, if samsung_dsim_register_te_irq() or
pdata->host_ops->attach() fails afterwards, the function returns
without removing the bridge, causing a memory leak.
Fix this by adding proper error handling with goto labels to ensure
drm_bridge_remove() is called in all error paths. Also ensure that
samsung_dsim_unregister_te_irq() is called if the attach operation
fails after the TE IRQ has been registered.
samsung_dsim_unregister_te_irq() function is moved without changes
to be before samsung_dsim_host_attach() to avoid forward declaration.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: add upper bound check on user inputs in wait ioctl
Huge input values in amdgpu_userq_wait_ioctl can lead to a OOM and
could be exploited.
So check these input value against AMDGPU_USERQ_MAX_HANDLES
which is big enough value for genuine use cases and could
potentially avoid OOM.
v2: squash in Srini's fix
(cherry picked from commit fcec012c664247531aed3e662f4280ff804d1476)
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu/userq: Fix reference leak in amdgpu_userq_wait_ioctl
Drop reference to syncobj and timeline fence when aborting the ioctl due
output array being too small.
(cherry picked from commit 68951e9c3e6bb22396bc42ef2359751c8315dd27)
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: add upper bound check on user inputs in signal ioctl
Huge input values in amdgpu_userq_signal_ioctl can lead to a OOM and
could be exploited.
So check these input value against AMDGPU_USERQ_MAX_HANDLES
which is big enough value for genuine use cases and could
potentially avoid OOM.
(cherry picked from commit be267e15f99bc97cbe202cd556717797cdcf79a5)
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
cpufreq: intel_pstate: Fix NULL pointer dereference in update_cpu_qos_request()
The update_cpu_qos_request() function attempts to initialize the 'freq'
variable by dereferencing 'cpudata' before verifying if the 'policy'
is valid.
This issue occurs on systems booted with the "nosmt" parameter, where
all_cpu_data[cpu] is NULL for the SMT sibling threads. As a result,
any call to update_qos_requests() will result in a NULL pointer
dereference as the code will attempt to access pstate.turbo_freq using
the NULL cpudata pointer.
Also, pstate.turbo_freq may be updated by intel_pstate_get_hwp_cap()
after initializing the 'freq' variable, so it is better to defer the
'freq' until intel_pstate_get_hwp_cap() has been called.
Fix this by deferring the 'freq' assignment until after the policy and
driver_data have been validated.
[ rjw: Added one paragraph to the changelog ]
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
kthread: consolidate kthread exit paths to prevent use-after-free
Guillaume reported crashes via corrupted RCU callback function pointers
during KUnit testing. The crash was traced back to the pidfs rhashtable
conversion which replaced the 24-byte rb_node with an 8-byte rhash_head
in struct pid, shrinking it from 160 to 144 bytes.
struct kthread (without CONFIG_BLK_CGROUP) is also 144 bytes. With
CONFIG_SLAB_MERGE_DEFAULT and SLAB_HWCACHE_ALIGN both round up to
192 bytes and share the same slab cache. struct pid.rcu.func and
struct kthread.affinity_node both sit at offset 0x78.
When a kthread exits via make_task_dead() it bypasses kthread_exit() and
misses the affinity_node cleanup. free_kthread_struct() frees the memory
while the node is still linked into the global kthread_affinity_list. A
subsequent list_del() by another kthread writes through dangling list
pointers into the freed and reused memory, corrupting the pid's
rcu.func pointer.
Instead of patching free_kthread_struct() to handle the missed cleanup,
consolidate all kthread exit paths. Turn kthread_exit() into a macro
that calls do_exit() and add kthread_do_exit() which is called from
do_exit() for any task with PF_KTHREAD set. This guarantees that
kthread-specific cleanup always happens regardless of the exit path -
make_task_dead(), direct do_exit(), or kthread_exit().
Replace __to_kthread() with a new tsk_is_kthread() accessor in the
public header. Export do_exit() since module code using the
kthread_exit() macro now needs it directly.
CVSS Score
9.8
EPSS Score
0.001
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
nsfs: tighten permission checks for ns iteration ioctls
Even privileged services should not necessarily be able to see other
privileged service's namespaces so they can't leak information to each
other. Use may_see_all_namespaces() helper that centralizes this policy
until the nstree adapts.
CVSS Score
8.8
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
mm: Fix a hmm_range_fault() livelock / starvation problem
If hmm_range_fault() fails a folio_trylock() in do_swap_page,
trying to acquire the lock of a device-private folio for migration,
to ram, the function will spin until it succeeds grabbing the lock.
However, if the process holding the lock is depending on a work
item to be completed, which is scheduled on the same CPU as the
spinning hmm_range_fault(), that work item might be starved and
we end up in a livelock / starvation situation which is never
resolved.
This can happen, for example if the process holding the
device-private folio lock is stuck in
migrate_device_unmap()->lru_add_drain_all()
sinc lru_add_drain_all() requires a short work-item
to be run on all online cpus to complete.
A prerequisite for this to happen is:
a) Both zone device and system memory folios are considered in
migrate_device_unmap(), so that there is a reason to call
lru_add_drain_all() for a system memory folio while a
folio lock is held on a zone device folio.
b) The zone device folio has an initial mapcount > 1 which causes
at least one migration PTE entry insertion to be deferred to
try_to_migrate(), which can happen after the call to
lru_add_drain_all().
c) No or voluntary only preemption.
This all seems pretty unlikely to happen, but indeed is hit by
the "xe_exec_system_allocator" igt test.
Resolve this by waiting for the folio to be unlocked if the
folio_trylock() fails in do_swap_page().
Rename migration_entry_wait_on_locked() to
softleaf_entry_wait_unlock() and update its documentation to
indicate the new use-case.
Future code improvements might consider moving
the lru_add_drain_all() call in migrate_device_unmap() to be
called *after* all pages have migration entries inserted.
That would eliminate also b) above.
v2:
- Instead of a cond_resched() in hmm_range_fault(),
eliminate the problem by waiting for the folio to be unlocked
in do_swap_page() (Alistair Popple, Andrew Morton)
v3:
- Add a stub migration_entry_wait_on_locked() for the
!CONFIG_MIGRATION case. (Kernel Test Robot)
v4:
- Rename migrate_entry_wait_on_locked() to
softleaf_entry_wait_on_locked() and update docs (Alistair Popple)
v5:
- Add a WARN_ON_ONCE() for the !CONFIG_MIGRATION
version of softleaf_entry_wait_on_locked().
- Modify wording around function names in the commit message
(Andrew Morton)
(cherry picked from commit a69d1ab971a624c6f112cea61536569d579c3215)
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: properly validate the data in rtw_get_ie_ex()
Just like in commit 154828bf9559 ("staging: rtl8723bs: fix out-of-bounds
read in rtw_get_ie() parser"), we don't trust the data in the frame so
we should check the length better before acting on it
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
mm/damon/core: clear walk_control on inactive context in damos_walk()
damos_walk() sets ctx->walk_control to the caller-provided control
structure before checking whether the context is running. If the context
is inactive (damon_is_running() returns false), the function returns
-EINVAL without clearing ctx->walk_control. This leaves a dangling
pointer to a stack-allocated structure that will be freed when the caller
returns.
This is structurally identical to the bug fixed in commit f9132fbc2e83
("mm/damon/core: remove call_control in inactive contexts") for
damon_call(), which had the same pattern of linking a control object and
returning an error without unlinking it.
The dangling walk_control pointer can cause:
1. Use-after-free if the context is later started and kdamond
dereferences ctx->walk_control (e.g., in damos_walk_cancel()
which writes to control->canceled and calls complete())
2. Permanent -EBUSY from subsequent damos_walk() calls, since the
stale pointer is non-NULL
Nonetheless, the real user impact is quite restrictive. The
use-after-free is impossible because there is no damos_walk() callers who
starts the context later. The permanent -EBUSY can actually confuse
users, as DAMON is not running. But the symptom is kept only while the
context is turned off. Turning it on again will make DAMON internally
uses a newly generated damon_ctx object that doesn't have the invalid
damos_walk_control pointer, so everything will work fine again.
Fix this by clearing ctx->walk_control under walk_control_lock before
returning -EINVAL, mirroring the fix pattern from f9132fbc2e83.
CVSS Score
7.8
EPSS Score
0.0
Published
2026-05-08