Linux: >> Linux Kernel >> 2.0.31 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: btsdio: fix use after free bug in btsdio_remove due to race condition
In btsdio_probe, the data->work is bound with btsdio_work. It will be
started in btsdio_send_frame.
If the btsdio_remove runs with a unfinished work, there may be a race
condition that hdev is freed but used in btsdio_work. Fix it by
canceling the work before do cleanup in btsdio_remove.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-05-10
In the Linux kernel, the following vulnerability has been resolved:
perf/core: Fix WARN_ON(!ctx) in __free_event() for partial init
Move the get_ctx(child_ctx) call and the child_event->ctx assignment to
occur immediately after the child event is allocated. Ensure that
child_event->ctx is non-NULL before any subsequent error path within
inherit_event calls free_event(), satisfying the assumptions of the
cleanup code.
Details:
There's no clear Fixes tag, because this bug is a side-effect of
multiple interacting commits over time (up to 15 years old), not
a single regression.
The code initially incremented refcount then assigned context
immediately after the child_event was created. Later, an early
validity check for child_event was added before the
refcount/assignment. Even later, a WARN_ON_ONCE() cleanup check was
added, assuming event->ctx is valid if the pmu_ctx is valid.
The problem is that the WARN_ON_ONCE() could trigger after the initial
check passed but before child_event->ctx was assigned, violating its
precondition. The solution is to assign child_event->ctx right after
its initial validation. This ensures the context exists for any
subsequent checks or cleanup routines, resolving the WARN_ON_ONCE().
To resolve it, defer the refcount update and child_event->ctx assignment
directly after child_event->pmu_ctx is set but before checking if the
parent event is orphaned. The cleanup routine depends on
event->pmu_ctx being non-NULL before it verifies event->ctx is
non-NULL. This also maintains the author's original intent of passing
in child_ctx to find_get_pmu_context before its refcount/assignment.
[ mingo: Expanded the changelog from another email by Gabriel Shahrouzi. ]
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
9p/net: fix improper handling of bogus negative read/write replies
In p9_client_write() and p9_client_read_once(), if the server
incorrectly replies with success but a negative write/read count then we
would consider written (negative) <= rsize (positive) because both
variables were signed.
Make variables unsigned to avoid this problem.
The reproducer linked below now fails with the following error instead
of a null pointer deref:
9pnet: bogus RWRITE count (4294967295 > 3)
CVSS Score
7.1
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
um: work around sched_yield not yielding in time-travel mode
sched_yield by a userspace may not actually cause scheduling in
time-travel mode as no time has passed. In the case seen it appears to
be a badly implemented userspace spinlock in ASAN. Unfortunately, with
time-travel it causes an extreme slowdown or even deadlock depending on
the kernel configuration (CONFIG_UML_MAX_USERSPACE_ITERATIONS).
Work around it by accounting time to the process whenever it executes a
sched_yield syscall.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
usb: xhci: Fix isochronous Ring Underrun/Overrun event handling
The TRB pointer of these events points at enqueue at the time of error
occurrence on xHCI 1.1+ HCs or it's NULL on older ones. By the time we
are handling the event, a new TD may be queued at this ring position.
I can trigger this race by rising interrupt moderation to increase IRQ
handling delay. Similar delay may occur naturally due to system load.
If this ever happens after a Missed Service Error, missed TDs will be
skipped and the new TD processed as if it matched the event. It could
be given back prematurely, risking data loss or buffer UAF by the xHC.
Don't complete TDs on xrun events and don't warn if queued TDs don't
match the event's TRB pointer, which can be NULL or a link/no-op TRB.
Don't warn if there are no queued TDs at all.
Now that it's safe, also handle xrun events if the skip flag is clear.
This ensures completion of any TD stuck in 'error mid TD' state right
before the xrun event, which could happen if a driver submits a finite
number of URBs to a buggy HC and then an error occurs on the last TD.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
s390/sclp: Add check for get_zeroed_page()
Add check for the return value of get_zeroed_page() in
sclp_console_init() to prevent null pointer dereference.
Furthermore, to solve the memory leak caused by the loop
allocation, add a free helper to do the free job.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix deadlock between rcu_tasks_trace and event_mutex.
Fix the following deadlock:
CPU A
_free_event()
perf_kprobe_destroy()
mutex_lock(&event_mutex)
perf_trace_event_unreg()
synchronize_rcu_tasks_trace()
There are several paths where _free_event() grabs event_mutex
and calls sync_rcu_tasks_trace. Above is one such case.
CPU B
bpf_prog_test_run_syscall()
rcu_read_lock_trace()
bpf_prog_run_pin_on_cpu()
bpf_prog_load()
bpf_tracing_func_proto()
trace_set_clr_event()
mutex_lock(&event_mutex)
Delegate trace_set_clr_event() to workqueue to avoid
such lock dependency.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
iommu: Clear iommu-dma ops on cleanup
If iommu_device_register() encounters an error, it can end up tearing
down already-configured groups and default domains, however this
currently still leaves devices hooked up to iommu-dma (and even
historically the behaviour in this area was at best inconsistent across
architectures/drivers...) Although in the case that an IOMMU is present
whose driver has failed to probe, users cannot necessarily expect DMA to
work anyway, it's still arguable that we should do our best to put
things back as if the IOMMU driver was never there at all, and certainly
the potential for crashing in iommu-dma itself is undesirable. Make sure
we clean up the dev->dma_iommu flag along with everything else.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
HID: pidff: Fix null pointer dereference in pidff_find_fields
This function triggered a null pointer dereference if used to search for
a report that isn't implemented on the device. This happened both for
optional and required reports alike.
The same logic was applied to pidff_find_special_field and although
pidff_init_fields should return an error earlier if one of the required
reports is missing, future modifications could change this logic and
resurface this possible null pointer dereference again.
LKML bug report:
https://lore.kernel.org/all/CAL-gK7f5=R0nrrQdPtaZZr1fd-cdAMbDMuZ_NLA8vM0SX+nGSw@mail.gmail.com
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: handle amdgpu_cgs_create_device() errors in amd_powerplay_create()
Add error handling to propagate amdgpu_cgs_create_device() failures
to the caller. When amdgpu_cgs_create_device() fails, release hwmgr
and return -ENOMEM to prevent null pointer dereference.
[v1]->[v2]: Change error code from -EINVAL to -ENOMEM. Free hwmgr.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-09