Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
drm: Set old handle to NULL before prime swap in change_handle
There was a potential race condition in change_handle. The ioctl
briefly had a single object with two idr entries; a concurrent
gem_close could delete the object and remove one of the handles
while leaving the other one dangling, which could subsequently
be dereferenced for a use-after-free.
To fix this, do the same dance that gem_close itself does.
(f6cd7daecff5 drm: Release driver references to handle before making it available again)
First idr_replace the old handle to NULL. Later, if the prime
operations are successful, actually close it.
create_tail required a similar dance to avoid a similar problem.
(bd46cece51a3 drm/gem: Fix race in drm_gem_handle_create_tail())
It idr_allocs the new handle with NULL, then swaps in the correct
object later to avoid races. We don't need to do that here, since
the only operations that could race are drm_prime, and
change_handle holds the prime lock for the entire duration.
v2: cleanups of error paths
CVSS Score
7.8
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
drm/xe/hdcp: Add NULL check for media_gt in intel_hdcp_gsc_check_status()
When media GT is disabled via configfs, there is no allocation for
media_gt, which is kept as NULL. In such scenario,
intel_hdcp_gsc_check_status() results in a kernel pagefault error due to
>->uc.gsc being evaluated as an invalid memory address.
Fix that by introducing a NULL check on media_gt and bailing out early
if so.
While at it, also drop the NULL check for gsc, since it can't be NULL if
media_gt is not NULL.
v2:
- Get address for gsc only after checking that gt is not NULL.
(Shuicheng)
- Drop the NULL check for gsc. (Shuicheng)
v3:
- Add "Fixes" and "Cc: <stable...>" tags. (Matt)
(cherry picked from commit bfaf87e84ca3ca3f6e275f9ae56da47a8b55ffd1)
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu/vcn4: Avoid overflow on msg bound check
As pointed out by SDL, the previous condition may be vulnerable to
overflow.
(cherry picked from commit 3c5367d950140d4ec7af830b2268a5a6fdaa3885)
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Add bounds checking to ib_{get,set}_value
The uvd/vce/vcn code accesses the IB at predefined offsets without
checking that the IB is large enough. Check the bounds here. The caller
is responsible for making sure it can handle arbitrary return values.
Also make the idx a uint32_t to prevent overflows causing the condition
to fail.
CVSS Score
7.1
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
spi: mpc52xx: fix use-after-free on unbind
The state machine work is scheduled by the interrupt handler and
therefore needs to be cancelled after disabling interrupts to avoid a
potential use-after-free.
CVSS Score
7.8
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu/sdma4: replace BUG_ON with WARN_ON in fence emission
sdma_v4_0_ring_emit_fence() contains two BUG_ON(addr & 0x3) assertions
that verify fence writeback addresses are dword-aligned. These
assertions can be reached from unprivileged userspace via crafted
DRM_IOCTL_AMDGPU_CS submissions, causing a fatal kernel panic in a
scheduler worker thread.
Replace both BUG_ON() calls with WARN_ON() to log the condition without
crashing the kernel. A misaligned fence address at this point indicates
a driver bug, but crashing the kernel is never the correct response when
the assertion is reachable from userspace.
The CS IOCTL path is the correct place to filter invalid submissions;
the ring emission callback is too late to do anything about it.
(cherry picked from commit b90250bd933afd1ba94d86d6b13821997b22b18e)
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
EDAC/versalnet: Fix device name memory leak
The device name allocated via kzalloc() in init_one_mc() is assigned to
dev->init_name but never freed on the normal removal path. device_register()
copies init_name and then sets dev->init_name to NULL, so the name pointer
becomes unreachable from the device. Thus leaking memory.
Use a stack-local char array instead of using kzalloc() for name.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
media: rockchip: rkcif: Add missing MUST_CONNECT flag to pads
The pads missed checks for connected devices which may a null dereference
when the stream is enabled.
Unable to handle kernel NULL pointer dereference at virtual address
0000000000000020
pc : rkcif_interface_enable_streams+0x48/0xf0
lr : rkcif_interface_enable_streams+0x44/0xf0
Call trace:
rkcif_interface_enable_streams+0x48/0xf0
v4l2_subdev_enable_streams+0x26c/0x3f0
rkcif_stream_start_streaming+0x140/0x278
vb2_start_streaming+0x74/0x188
vb2_core_streamon+0xe0/0x1d8
vb2_ioctl_streamon+0x60/0xa8
v4l_streamon+0x2c/0x40
__video_do_ioctl+0x34c/0x400
video_usercopy+0x2d0/0x800
video_ioctl2+0x20/0x60
v4l2_ioctl+0x48/0x78
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
cgroup: Defer css percpu_ref kill on rmdir until cgroup is depopulated
A chain of commits going back to v7.0 reworked rmdir to satisfy the
controller invariant that a subsystem's ->css_offline() must not run while
tasks are still doing kernel-side work in the cgroup.
[1] d245698d727a ("cgroup: Defer task cgroup unlink until after the task is done switching out")
[2] a72f73c4dd9b ("cgroup: Don't expose dead tasks in cgroup")
[3] 1b164b876c36 ("cgroup: Wait for dying tasks to leave on rmdir")
[4] 4c56a8ac6869 ("cgroup: Fix cgroup_drain_dying() testing the wrong condition")
[5] 13e786b64bd3 ("cgroup: Increment nr_dying_subsys_* from rmdir context")
[1] moved task cset unlink from do_exit() to finish_task_switch() so a
task's cset link drops only after the task has fully stopped scheduling.
That made tasks past exit_signals() linger on cset->tasks until their final
context switch, which led to a series of problems as what userspace expected
to see after rmdir diverged from what the kernel needs to wait for. [2]-[5]
tried to bridge that divergence: [2] filtered the exiting tasks from
cgroup.procs; [3] had rmdir(2) sleep in TASK_UNINTERRUPTIBLE for them; [4]
fixed the wait's condition; [5] made nr_dying_subsys_* visible
synchronously.
The cgroup_drain_dying() wait in [3] turned out to be a dead end. When the
rmdir caller is also the reaper of a zombie that pins a pidns teardown (e.g.
host PID 1 systemd reaping orphan pids that were re-parented to it during
the same teardown), rmdir blocks in TASK_UNINTERRUPTIBLE waiting for those
pids to free, the pids can't free because PID 1 is the reaper and it's stuck
in rmdir, and the system A-A deadlocks. No internal lock ordering breaks
this; the wait itself is the bug.
The css killing side that drove the original reorder, however, can be made
cleanly asynchronous: ->css_offline() is already async, run from
css_killed_work_fn() driven by percpu_ref_kill_and_confirm(). The fix is to
make that chain start only after all tasks have left the cgroup. rmdir's
user-visible side then returns as soon as cgroup.procs and friends are
empty, while ->css_offline() still runs only after the cgroup is fully
drained.
Verified by the original reproducer (pidns teardown + zombie reaper, runs
under vng) which hangs vanilla and succeeds here, and by per-commit
deterministic repros for [2], [3], [4], [5] with a boot parameter that
widens the post-exit_signals() window so each state is reliably reachable.
Some stress tests on top of that.
cgroup_apply_control_disable() has the same shape of pre-existing race:
when a controller is disabled via subtree_control, kill_css() ran
synchronously while tasks past exit_signals() could still be linked to
the cgroup's csets, and ->css_offline() could fire before they drained.
This patch preserves the existing synchronous behavior at that call site
(kill_css_sync() + kill_css_finish() back-to-back) and a follow-up patch
will defer kill_css_finish() there using a per-css trigger.
This seems like the right approach and I don't see problems with it. The
changes are somewhat invasive but not excessively so, so backporting to
-stable should be okay. If something does turn out to be wrong, the fallback
is to revert the entire chain ([1]-[5]) and rework in the development branch
instead.
v2: Pin cgrp across the deferred destroy work with explicit
cgroup_get()/cgroup_put() around queue_work() and the work_fn. v1
wasn't actually broken (ordered cgroup_offline_wq + queue_work order
in cgroup_task_dead() saved it) but the explicit ref removes the
dependency on those non-obvious invariants. Also note the
pre-existing cgroup_apply_control_disable() race in the description;
a follow-up will defer kill_css_finish() there.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu/vcn4: Prevent OOB reads when parsing IB
Rewrite the IB parsing to use amdgpu_ib_get_value() which handles the
bounds checks.
CVSS Score
7.1
EPSS Score
0.0
Published
2026-05-28