| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: fix UAF in cleanup_bearer() due to premature dst_cache_destroy()
TIPC UDP media bearer teardown calls dst_cache_destroy() on its
replicast caches before calling synchronize_net() to wait for
concurrent RCU readers (transmitters) to finish:
static void cleanup_bearer(struct work_struct *work)
{
...
list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
dst_cache_destroy(&rcast->dst_cache);
list_del_rcu(&rcast->list);
kfree_rcu(rcast, rcu);
}
...
dst_cache_destroy(&ub->rcast.dst_cache);
udp_tunnel_sock_release(ub->sk);
synchronize_net();
...
}
This is highly buggy because dst_cache_destroy() immediately frees the
per-CPU cache memory (free_percpu()) and releases the cached dst
entries without any synchronization.
If a concurrent transmitter (e.g., tipc_udp_xmit()) is running on another
CPU under RCU protection, it can call dst_cache_get() concurrently,
leading to:
1. Use-After-Free on the per-CPU cache pointer itself (crash).
2. "rcuref - imbalanced put()" warning if it attempts to release a
dst that was concurrently released by dst_cache_destroy().
Furthermore, calling kfree(ub) immediately after synchronize_net() without
closing the socket first (or waiting after closing it) leaves a window
where a concurrent receiver (tipc_udp_recv()) could start after
synchronize_net(), access ub, and suffer a UAF when kfree(ub) runs.
To fix this, we must defer dst_cache_destroy() and kfree(ub) until after
we have ensured that no more readers can see the bearer/socket and all
existing readers have finished:
1. Defer rcast entry destruction (both dst_cache_destroy() and kfree())
to an RCU callback using call_rcu_hurry().
Using call_rcu_hurry() ensures the dst entries are released quickly.
2. Release the bearer socket using udp_tunnel_sock_release() (stops
new receive readers).
3. Call synchronize_net() to wait for all outstanding RCU readers
(both transmit and receive) to finish.
4. Now that it is safe, call dst_cache_destroy() on the main bearer
cache, and free ub.
Note: 3) and 4) can be changed later in net-next to also use
call_rcu_hurry() and get rid of the synchronize_net() latency. |
| In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Avoid NULL pointer dereference or refcount corruption
Commit 60f030f7418d ("iommu/vt-d: Avoid use of NULL after WARN_ON_ONCE")
fixed a NULL pointer dereference in an unlikely situation partly.
If dev_pasid is not found in the dev_pasids list, it remains NULL.
However, the teardown operations are executed unconditionally, this lead
to a NULL pointer dereference or refcount corruption.
If the domain was never attached to this IOMMU, info will be NULL, which
would cause an immediate dereference when checking --info->refcnt.
Even if info is not NULL, decrementing the refcount without having removed
a valid PASID might unbalance the count. This could lead to premature
dropping of the refcount to 0, potentially causing a use-after-free for the
remaining active devices sharing the domain.
Fix it by returning early if dev_pasid is NULL, before executing the
teardown operations.
Issue found by AI review and suggested by Kevin Tian.
https://sashiko.dev/#/patchset/20260421031347.1408890-1-zhenzhong.duan%40intel.com |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Cancel the running bpf_timer through kworker for PREEMPT_RT
During the update procedure, when overwrite element in a pre-allocated
htab, the freeing of old_element is protected by the bucket lock. The
reason why the bucket lock is necessary is that the old_element has
already been stashed in htab->extra_elems after alloc_htab_elem()
returns. If freeing the old_element after the bucket lock is unlocked,
the stashed element may be reused by concurrent update procedure and the
freeing of old_element will run concurrently with the reuse of the
old_element. However, the invocation of check_and_free_fields() may
acquire a spin-lock which violates the lockdep rule because its caller
has already held a raw-spin-lock (bucket lock). The following warning
will be reported when such race happens:
BUG: scheduling while atomic: test_progs/676/0x00000003
3 locks held by test_progs/676:
#0: ffffffff864b0240 (rcu_read_lock_trace){....}-{0:0}, at: bpf_prog_test_run_syscall+0x2c0/0x830
#1: ffff88810e961188 (&htab->lockdep_key){....}-{2:2}, at: htab_map_update_elem+0x306/0x1500
#2: ffff8881f4eac1b8 (&base->softirq_expiry_lock){....}-{2:2}, at: hrtimer_cancel_wait_running+0xe9/0x1b0
Modules linked in: bpf_testmod(O)
Preemption disabled at:
[<ffffffff817837a3>] htab_map_update_elem+0x293/0x1500
CPU: 0 UID: 0 PID: 676 Comm: test_progs Tainted: G ... 6.12.0+ #11
Tainted: [W]=WARN, [O]=OOT_MODULE
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)...
Call Trace:
<TASK>
dump_stack_lvl+0x57/0x70
dump_stack+0x10/0x20
__schedule_bug+0x120/0x170
__schedule+0x300c/0x4800
schedule_rtlock+0x37/0x60
rtlock_slowlock_locked+0x6d9/0x54c0
rt_spin_lock+0x168/0x230
hrtimer_cancel_wait_running+0xe9/0x1b0
hrtimer_cancel+0x24/0x30
bpf_timer_delete_work+0x1d/0x40
bpf_timer_cancel_and_free+0x5e/0x80
bpf_obj_free_fields+0x262/0x4a0
check_and_free_fields+0x1d0/0x280
htab_map_update_elem+0x7fc/0x1500
bpf_prog_9f90bc20768e0cb9_overwrite_cb+0x3f/0x43
bpf_prog_ea601c4649694dbd_overwrite_timer+0x5d/0x7e
bpf_prog_test_run_syscall+0x322/0x830
__sys_bpf+0x135d/0x3ca0
__x64_sys_bpf+0x75/0xb0
x64_sys_call+0x1b5/0xa10
do_syscall_64+0x3b/0xc0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
...
</TASK>
It seems feasible to break the reuse and refill of per-cpu extra_elems
into two independent parts: reuse the per-cpu extra_elems with bucket
lock being held and refill the old_element as per-cpu extra_elems after
the bucket lock is unlocked. However, it will make the concurrent
overwrite procedures on the same CPU return unexpected -E2BIG error when
the map is full.
Therefore, the patch fixes the lock problem by breaking the cancelling
of bpf_timer into two steps for PREEMPT_RT:
1) use hrtimer_try_to_cancel() and check its return value
2) if the timer is running, use hrtimer_cancel() through a kworker to
cancel it again
Considering that the current implementation of hrtimer_cancel() will try
to acquire a being held softirq_expiry_lock when the current timer is
running, these steps above are reasonable. However, it also has
downside. When the timer is running, the cancelling of the timer is
delayed when releasing the last map uref. The delay is also fixable
(e.g., break the cancelling of bpf timer into two parts: one part in
locked scope, another one in unlocked scope), it can be revised later if
necessary.
It is a bit hard to decide the right fix tag. One reason is that the
problem depends on PREEMPT_RT which is enabled in v6.12. Considering the
softirq_expiry_lock lock exists since v5.4 and bpf_timer is introduced
in v5.15, the bpf_timer commit is used in the fixes tag and an extra
depends-on tag is added to state the dependency on PREEMPT_RT.
Depends-on: v6.12+ with PREEMPT_RT enabled |
| Use after free in Windows Update Orchestrator Service allows an authorized attacker to elevate privileges locally. |
| Use after free in Windows Bind Filter Driver allows an authorized attacker to elevate privileges locally. |
| In the Linux kernel, the following vulnerability has been resolved:
audit: fix exe mark UAF in kill_rules()
kill_rules() removes mixed AUDIT_DIR and AUDIT_EXE rules when an audit
tree is pruned. It drops entry->rule.exe before removing the rule from
the RCU-visible filter lists.
After a rule has been installed with AUDIT_ADD_RULE, which requires
CAP_AUDIT_CONTROL, removing the watched directory can race with another
task that is still evaluating the rule. In that case, fsnotify can free
the executable mark before the reader reaches audit_mark_compare(),
causing a use-after-free.
KASAN reports:
BUG: KASAN: slab-use-after-free in audit_mark_compare+0x8d/0xa0
Unlink the published rules from the RCU-visible lists and retain them
on tree->rules for cleanup. If any rule has an executable mark, wait for
a single RCU grace period before removing the marks and scheduling the
entries for freeing. Otherwise, call_rcu() already provides the required
deferred freeing without a synchronous wait. |
| In the Linux kernel, the following vulnerability has been resolved:
HID: multitouch: stop the release timer from being rearmed on remove
mt_remove() quiesces the sticky-finger timer before stopping the
hardware:
timer_delete_sync(&td->release_timer);
sysfs_remove_group(&hdev->dev.kobj, &mt_attribute_group);
hid_hw_stop(hdev);
timer_delete_sync() waits for a running callback and dequeues the timer,
but it does not stop the timer from being armed again. The transport is
still delivering reports at that point, and the report path rearms it:
if (app->quirks & MT_QUIRK_STICKY_FINGERS) {
if (td->mt_io_flags & MT_IO_SLOTS_MASK)
mod_timer(&td->release_timer,
jiffies + msecs_to_jiffies(100));
A report that arrives after timer_delete_sync() has returned therefore
leaves the timer queued. td is allocated with devm_kzalloc() against
hdev->dev, so it is freed when the driver is unbound, after mt_remove()
returns. When the timer fires afterwards, mt_expired_timeout()
dereferences the freed td:
struct mt_device *td = timer_container_of(td, t, release_timer);
struct hid_device *hdev = td->hdev;
if (test_and_set_bit_lock(MT_IO_FLAGS_RUNNING, &td->mt_io_flags))
Simply moving the teardown after hid_hw_stop() does not fix this on its
own, because mt_expired_timeout() calls mt_release_contacts(), which
walks hdev->inputs; the timer still has to be quiesced before
hid_hw_stop() tears the input devices down.
Use timer_shutdown_sync() instead, which additionally makes any later
mod_timer() a no-op, so neither ordering constraint has to be traded off
against the other. This is the final-teardown pattern the function was
introduced for, and hid-wiimote already uses it for the same reason. |
| In the Linux kernel, the following vulnerability has been resolved:
of/overlay: put property on deadprops only after changeset add succeeds
add_changeset_property() links a new property of a not-yet-live
target node into the node's deadprops list before handing it to
of_changeset_add_property(). If that fails, the error path frees the
property but leaves the freed pointer linked in deadprops, and
of_node_release() frees it a second time when the aborted overlay's
node is released.
Record the changeset entry first and link the property into deadprops
only on success. of_changeset_add_property() never looks at the
node's property lists, so the order of the two steps is otherwise
immaterial, and the error path frees a property that nothing
references. |
| In the Linux kernel, the following vulnerability has been resolved:
net: extend IPv6 exthdr detection of tunneled packets
Commit c4336a07eb6b ("net: correctly handle tunneled traffic on IPV6_CSUM
GSO fallback") split skb_gso_has_extension_hdr() into mutually exclusive
branches on skb->encapsulation. This did not yet address all paths:
1. With skb->encapsulation set, the outer header is not checked. IPv6
tunnels such as ip6_gre and ip6_tunnel add an outer Destination
Options header by default (encap_limit). Their GSO packets skip
software GSO, then skb_csum_hwoffload_help() sees the outer extension
header and calls skb_checksum_help() on the GSO skb, which warns and
drops it.
2. Tunnels over IPv6 without an outer transport header, such as
ip6_tunnel, leave skb->transport_header at the inner transport
header. skb_network_header_len() then spans the outer IPv6, tunnel
and inner IP headers, a false positive.
3. UDP tunnels without an inner network header, such as SCTP-in-UDP or
PSP, have no inner IPv6 header to check. Decide on the outer header
alone.
4. Directly dereferencing inner_ip_hdr(skb)->version without
skb_header_pointer() is unsafe.
Instead, check ipv6_ext_hdr(nexthdr) on the outer IPv6 header and, if
set, on the inner IPv6 header. Read the headers with skb_header_pointer().
Keep the skb_network_header_len() check when !skb->encapsulation to also
catch encapsulated packets without skb->encapsulation (e.g., virtio).
Use the same helper in skb_csum_hwoffload_help(). Its open coded test
has the false positive of (2) and ignores the inner header.
Background: checksum offload of tunneled packets invariants:
Non-GSO skb:
- If the inner packet is CHECKSUM_PARTIAL, Local Checksum Offload computes
the outer checksum in software and the device offloads only the inner L4
checksum.
- If the inner packet is CHECKSUM_NONE (e.g., SCTP-in-UDP, ESP-in-UDP,
Remote Checksum Offload), the device offloads the outer UDP or GRE
checksum instead.
GSO skb:
- A device with NETIF_F_GSO_UDP_TUNNEL_CSUM or NETIF_F_GSO_GRE_CSUM
computes both inner and outer checksums per segment.
The outer checksum is seeded with only the pseudo-header checksum.
A NETIF_F_IPV6_CSUM device must parse through the outer headers to
reach the inner ones. |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: check RCV_SHUTDOWN after the sendmsg connect wait
sctp_wait_for_connect() drops the socket lock while it sleeps. An
out-of-the-blue ABORT can then be processed from the socket backlog and
unlink the association. If a concurrent shutdown(fd, SHUT_RD) sets
RCV_SHUTDOWN, the waiter breaks with err == 0 before checking
asoc->base.dead. Its final sctp_association_put() can then free the
association, leaving sctp_sendmsg_to_asoc() to continue with a dangling
pointer.
Check RCV_SHUTDOWN along with the wait error in sctp_sendmsg_to_asoc()
before using the association again. The check only accesses the socket,
so it needs no additional association reference. Return the existing
-ESRCH so that sctp_sendmsg() skips freeing a new association that may
already have been destroyed.
Keep sctp_wait_for_connect() unchanged to preserve its behavior for the
connect() caller. |
| In the Linux kernel, the following vulnerability has been resolved:
vc_screen: reload vc pointer before if (ret) in vcs_write() to avoid UAF
The reload of 'vc' added by commit 8fb9ea65c9d1 ("vc_screen: reload load
of struct vc_data pointer in vcs_write() to avoid UAF") sits after the
'if (ret)' block, so the copy-failure break path exits the loop without
reloading vc. If the vc was kfree()'d via vc_port_destruct during the
unlocked copy_from_user() window, the post-loop
'if (written && vc) vcs_scr_updated(vc)' is reached with a stale
non-NULL vc. The '&& vc' guard from commit a287620312dc ("vc_screen:
fix null-ptr-deref in vcs_notifier() during concurrent vcs_write") only
handles the NULL case, not this stale-non-NULL case; vcs_notifier() then
reads param->vc->vc_num from freed memory:
BUG: KASAN: slab-use-after-free in vcs_notifier+0x7c/0xd0
Read of size 2 at addr ffff888007149190
Call Trace:
vcs_notifier+0x7c/0xd0
atomic_notifier_call_chain+0x70/0xa0
vcs_scr_updated+0x77/0xa0
vcs_write+0x71b/0x7e0
Allocated by task: vc_allocate -> con_install -> tty_open
Freed by task: kfree <- vt_ioctl (VT_DISALLOCATE -> vc_port_destruct)
Move the reload to immediately after console_lock(), before 'if (ret)',
so every break path below passes a fresh vc to the post-loop
vcs_scr_updated(). |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: caiaq: unregister the input device when probe fails
setup_card() registers the input device, whose name and phys point into
struct snd_usb_caiaqdev, and then goes on to snd_card_register() and
snd_usb_caiaq_control_init(). If either fails, snd_probe() calls
snd_card_free(), which frees the device state but leaves the input
device registered: card_free() only clears the pointer, and the input
device is unregistered from snd_disconnect() alone. Reading its "uevent"
attribute afterwards dereferences freed memory:
BUG: KASAN: slab-use-after-free in string+0x4a9/0x4f0
Read of size 1 at addr ffff8880208f5043 by task caiaq/4967
add_uevent_var+0x183/0x3a0
input_dev_uevent+0x162/0x900
dev_uevent+0x2f1/0x870
uevent_show+0x1ca/0x3a0
...
Unregister the input device on the probe error path, as
snd_disconnect() does. snd_usb_caiaq_input_disconnect() is a no-op when
no input device was registered.
Reproduced with a raw-gadget Audio Kontrol 1 and a temporary hack that
makes snd_usb_caiaq_control_init() fail. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: cfg80211: preserve hidden-group beacon IE ownership
A hidden-group probe-response entry borrows its beacon IEs from the
group's beacon entry. cfg80211_update_assoc_bss_entry() can pass such
an entry to cfg80211_update_known_bss() when merging scan entries
after a channel switch.
Copying the borrowed beacon_ies into the associated entry gives the
same allocation two owners. Releasing the group's beacon entry can
then leave the associated entry pointing to freed IEs, which are
freed again when that entry is released.
Skip beacon IE replacement when the source entry belongs to a hidden
group. Preserve probe-response processing, the subsequent metadata
updates, and the existing rejection path for conflicting hidden
beacon updates. |
| In the Linux kernel, the following vulnerability has been resolved:
USB: serial: fix port tear down use-after-free
Some drivers for multiport devices access port driver data from
completion handlers of shared URBs submitted at attach() or first open()
and stopped at disconnect() or last close(), respectively.
A simple NULL check before accessing the driver data makes sure that a
port state container has at least been allocated, but a completion
handler can still race with port tear down.
Reorder the disconnect handling so that ports are not deregistered (and
their driver data freed) until after all ports have been hung up and the
driver disconnect() callback has run so that all I/O has been stopped. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: typec: anx7411 - stop the IRQ before destroying the workqueue
The IRQ is devm-managed, so it can still queue plat->work while
remove() is tearing the queue down. Disable it first. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: aspeed-vhub: cancel wake work on device removal
wake_work is armed from the gadget .wakeup callback to resume suspended
downstream ports, and it is never cancelled in ast_vhub_remove(), so a
work item queued before or during removal can run after devm has freed
vhub and its ports, a use-after-free.
Cancelling the work alone is not sufficient: usb_gadget_wakeup() takes
no lock and the unbind path never clears wakeup_en, so a remote-wakeup
request in flight on another CPU can re-arm the work after the cancel
and before vhub is freed.
ast_vhub_del_dev() already clears d->registered under vhub->lock before
unregistering the gadget. Refuse the wakeup in ast_vhub_udc_wakeup()
once d->registered is clear: the check and the schedule_work() are then
atomic against the unbind, so a wakeup that passed before the flag was
cleared is drained by the cancel_work_sync() after the del_dev loop,
and one that arrives later returns without arming. Also move INIT_WORK()
to the top of ast_vhub_probe(), since the probe error path reuses
ast_vhub_remove() and would otherwise cancel a never-initialized work
item.
This issue was found by an in-house static analysis tool. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: core: clear both ep_in and ep_out for non-ep0 control endpoints
In usb_enable_endpoint(), non-zero control endpoints (where
usb_endpoint_xfer_control(&ep->desc) is true) populate both
dev->ep_in[epnum] and dev->ep_out[epnum] with the same struct
usb_host_endpoint pointer.
However, usb_disable_endpoint() only clears either dev->ep_out[epnum] or
dev->ep_in[epnum] depending on the direction bit of epaddr when
reset_hardware is set, leaving the opposite direction's array slot
pointing to the disabled/freed endpoint.
Clear both dev->ep_out[epnum] and dev->ep_in[epnum] when disabling a
non-ep0 control endpoint with reset_hardware set, and update the
function kerneldoc accordingly.
Tested in QEMU against Linux 7.3.0-rc3 using dummy_hcd and raw-gadget to
enumerate a USB device with a non-zero control endpoint
(bEndpointAddress 0x01, bmAttributes USB_ENDPOINT_XFER_CONTROL),
verifying that both dev->ep_in[1] and dev->ep_out[1] are cleared when
the interface is disabled. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: cdns3: fix use-after-free in cdns3_gadget_exit()
cdns3_gadget_start() arms two works on system_freezable_wq:
pending_status_wq for the deferred ep0 status stage and aligned_buf_wq
for realigned request buffers. Both handlers use the cdns3_device the
works are embedded in, and cdns3_pending_setup_status_handler() also
calls the ep0 request completion.
cdns3_gadget_exit() does not wait for these works. It frees all
endpoints and aligned buffers and drops the last reference to the
gadget device, which frees priv_dev, so a work queued before the exit
can run after the free.
Fix this by waiting for both works after the gadget driver is unbound
and the IRQ is freed, when no new work can be queued, and before the
endpoints and buffers are released.
This issue was found by an in-house static analysis tool. |
| In the Linux kernel, the following vulnerability has been resolved:
tty: vcc: hold port lock when clearing tty pointer in vcc_cleanup
vcc_cleanup() sets port->tty to NULL without holding port->lock, racing
with vcc_event() LDC callbacks that read port->tty under port->lock and
then use tty->port. This can cause a use-after-free when the callback
dereferences tty->port after cleanup has already destroyed and freed it. |
| In the Linux kernel, the following vulnerability has been resolved:
tty: port: fix tty_port_tty_vhangup() race
Drivers rely on tty_port_tty_vhangup() to synchronously hang up their
ports before tearing down resources as part of deregistration (e.g. on
physical disconnect).
If tty_port_tty_vhangup() races with another hangup it may however
return before the port has been shut down. This is in turn can lead to
use-after-free and NULL-pointer dereferences in racing ioctls (including
a synchronous hangup) and in processing of racing asynchronous hangups
(carrier loss).
Add the missing serialisation to tty_port_tty_vhangup() and
tty_port_hangup() so that the former does not return until the port has
been shut down also when there is a racing hangup.
Note that serial core does not use tty_port_hangup(), but it already
holds the port mutex when clearing port->tty and shutting down the port
in uart_hangup(). |
