| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: mcast: use rcu_assign_pointer() for __rcu list updates
Several places in net/ipv6/mcast.c update RCU-protected lists
(np->ipv6_mc_list, idev->mc_list, idev->mc_tomb) using direct pointer
assignments instead of rcu_assign_pointer():
1. In __ipv6_dev_mc_dec(), unlinking a group from idev->mc_list did:
*map = ma->next;
without rcu_assign_pointer() while concurrent readers traverse
idev->mc_list locklessly under rcu_read_lock().
2. In ipv6_sock_mc_drop() and __ipv6_sock_mc_close(), unlinking a group
from np->ipv6_mc_list directly assigned *lnk = mc_lst->next and
np->ipv6_mc_list = mc_lst->next without rcu_assign_pointer(), racing
with lockless readers in inet6_mc_check().
3. In __ipv6_sock_mc_join(), mc_lst->next was initialized to
np->ipv6_mc_list via raw assignment before publishing mc_lst.
4. In mld_del_delrec() and __ipv6_dev_mc_inc(), __rcu source pointers
passed into rcu_assign_pointer() lacked explicit dereference helpers.
Fix these by consistently using rcu_assign_pointer() along with
mc_dereference() / sock_dereference(). |
| In the Linux kernel, the following vulnerability has been resolved:
x86/kvm: Don't consume async #PF flags on a kernel #PF in NMI context
An async #PF "page not present" event arrives through the #PF vector,
and its reason sits in the per-CPU apf_reason.flags until
__kvm_handle_async_pf() reads and clears it. If an NMI arrives after
the event is injected and before the #PF handler reads the flags, and
the NMI handler itself takes a #PF, that fault reads and clears the
flags belonging to the #PF it interrupted. It then finds interrupts
disabled in the NMI context it interrupted, and panics:
Kernel panic - not syncing: Host injected async #PF in interrupt
disabled region
Call Trace:
<NMI>
panic+0x52/0x60
__kvm_handle_async_pf+0xb0/0xb0
exc_page_fault+0x71/0xb0
asm_exc_page_fault+0x27/0x30
RIP: 0010:__get_user_nocheck_8+0x6/0x20
perf_callchain_user+0x147/0x1a0
get_perf_callchain+0x12d/0x1c0
...
perf_event_nmi_handler+0x26/0x50
exc_nmi+0xe8/0x110
RIP: 0010:asm_exc_page_fault+0x0/0x30
</NMI>
The last RIP line shows the NMI landing on the first instruction of
the #PF entry. perf with user call chains takes such a fault: the
sampling NMI walks the user stack with __get_user(), which faults when
a saved frame pointer is not a valid user address or the walk runs off
the top of the stack. The same window exists when KVM, running as an
L1 hypervisor with DELIVERY_AS_PF_VMEXIT, reads the flags itself after
a #PF VM-exit.
The NMI entry code saves and restores CR2 for this nesting, but not the
async #PF reason. Andy Lutomirski described the race, with perf as the
example, when async #PF delivery was reworked in 2020 [1]. Saving and
clearing the flags across the NMI, next to CR2, was discussed there but
not merged.
Since that rework, Linux has stopped setting KVM_ASYNC_PF_SEND_ALWAYS,
so the host delivers "page not present" only for user mode faults and
a kernel-mode fault in NMI context (including kernel-mode #MC and #DB)
cannot be an async page fault. In that case, return without touching
the flags so that the interrupted handler finds them intact.
Tested on v7.3-rc5 in a 4-vCPU, 2 GiB guest restored from a snapshot
whose memory is served on demand through userfaultfd, so that reading
it back takes async #PFs, while every thread samples hardware cycles
with user call chains and points its frame pointer at an unmapped page.
Without this patch the guest panicked as above in 3 of 3 runs. With it,
the guest survived 3 of 3 runs of 60 seconds, and the host counted
148,441 to 153,334 kvm_async_pf_not_present events in the first 20
seconds of each. On 6.18.50 the results were the same: the guest
panicked without the patch and survived with it. |
| In the Linux kernel, the following vulnerability has been resolved:
vhost: reset the vring metadata cache on vring reconfiguration
vq->meta_iotlb[] caches the vhost_iotlb_map that backs each vring
metadata region, and iotlb_access_ok() returns early on a cache hit,
taking the hit as proof that the region has already been validated:
if (vhost_vq_meta_fetch(vq, addr, len, type))
return true;
The cache is reset on VHOST_IOTLB_UPDATE and VHOST_IOTLB_INVALIDATE, on
device IOTLB (re)initialisation and on vq reset, but not when
VHOST_SET_VRING_ADDR replaces vq->desc, vq->avail and vq->used, nor when
VHOST_SET_VRING_NUM changes the region sizes.
With a device IOTLB attached both ioctls are accepted while the vq is
live, and neither validates the addresses at ioctl time: vq_access_ok()
and vq_log_used_access_ok() return true early because the addresses are
GIOVAs, deferring validation to prefetch time. Once the cache has been
populated that deferred validation no longer runs -- vq_meta_prefetch()
hits the stale entry and returns true -- and vhost_vq_meta_fetch() keeps
translating through the old mapping as
map->addr + addr - map->start
for an address the mapping no longer covers. vhost_copy_to_user() and
vhost_copy_from_user() consume the result with __copy_to_user() and
__copy_from_user(), which do not check it either, so a subsequent used
ring update or descriptor fetch accesses memory outside the region the
IOTLB actually maps.
Reset the metadata cache whenever the vring is reconfigured, so the new
addresses are pushed back through iotlb_access_ok()'s slow path. |
| In the Linux kernel, the following vulnerability has been resolved:
net: skbuff: preserve shared-frag marker during coalescing
skb_try_coalesce() can attach paged frags from @from to @to. If @from
has SKBFL_SHARED_FRAG set, the resulting @to skb can contain the same
externally-owned or page-cache-backed frags, but the shared-frag marker
is currently lost.
That breaks the invariant relied on by later in-place writers. In
particular, ESP input checks skb_has_shared_frag() before deciding
whether an uncloned nonlinear skb can skip skb_cow_data(). If TCP
receive coalescing has moved shared frags into an unmarked skb, ESP can
see skb_has_shared_frag() as false and decrypt in place over page-cache
backed frags.
Propagate SKBFL_SHARED_FRAG when skb_try_coalesce() transfers paged
frags. The tailroom copy path does not need the marker because it copies
bytes into @to's linear data rather than transferring frag descriptors. |
| Use after free in Microsoft Edge (Chromium-based) allows an authorized attacker to execute code over a network. |
| In the Linux kernel, the following vulnerability has been resolved:
net: rds: fix uninitialized trans dereference in CM event handler
rds_rdma_cm_event_handler_cmn() assigns trans only when the RDMA
device is an InfiniBand CA (RDMA_NODE_IB_CA). On any other device
type, e.g. an iWARP RNIC such as siw, trans stays uninitialized, but
the event switch dereferences it: unconditionally in the
RDMA_CM_EVENT_CONNECT_REQUEST case via trans->cm_handle_connect(),
and (with a connection context) in the ROUTE_RESOLVED and
ESTABLISHED cases.
An RDS listener on an iWARP device therefore crashes the kernel as
soon as a connect request arrives: with CONFIG_INIT_STACK_ALL_ZERO
the wild load becomes a NULL dereference at offset 0xa0
(&trans->cm_handle_connect) in the iw_cm_wq workqueue.
GCC masks the bug in default builds by folding the uninitialized
load into &rds_ib_transport; Clang-built kernels take the real
uninitialized path and oops.
The active side can land on a non-IB device too: the id that
rds_ib_conn_path_connect() creates is not restricted to a node type,
so rdma_resolve_addr() binds it to whichever device serves the local
address, and an iWARP RNIC on the same netdev qualifies. The crash
there is different: resolving a route on an iWARP id never fills in
cm_id->route.path_rec, and the ROUTE_RESOLVED case writes
path_rec[0].sl before it calls into the transport.
The iWARP transport was dropped long ago and IB is the only
transport left, so make that explicit: initialize trans to
&rds_ib_transport at declaration, drop the conditional assignment,
reject a connect request that arrives on a non-IB device, and drop a
connection whose address resolved to one instead of resolving a
route on it. The rejection is limited to RDMA_CM_EVENT_CONNECT_REQUEST
on purpose: a non-zero return from the handler makes rdma_cm destroy
the id the event was delivered on, which is right for the request's
freshly created id but would free a connection id that RDS still owns
for any other event. On the active side the id stays ic->i_cm_id and
the connection's shutdown destroys it, so that case returns 0.
[achender: reject only on RDMA_CM_EVENT_CONNECT_REQUEST instead of
bailing out for every event on a non-IB device, so that rdma_cm does
not destroy connection ids RDS still tracks; drop a connection whose
address resolved to a non-IB device before a route is resolved on it;
changelog adjusted] |
| In the Linux kernel, the following vulnerability has been resolved:
watch_queue: Fix note pool publication race in watch_queue_set_size()
There is a race between watch_queue_set_size() and post_one_notification().
watch_queue_set_size() publishes wqueue->notes, notes_bitmap, nr_pages and
nr_notes with plain stores, and post_one_notification() reads them with
plain loads under a different lock, so nothing orders the four stores
against the poster's loads: depending on the build, notes can be stored
last (gcc 14 on x86-64 does this). Since keyctl_watch_key() lets a watch
attach to a queue before it is sized, post_one_notification() can already
be running on another CPU at that moment: it reads nr_notes > 0, passes
its bounds check, and then reads notes while it is still NULL,
dereferencing notes[0].
An unprivileged user triggers this reliably by watching one of its own
keys through a notification pipe and racing ioctl(IOC_WATCH_QUEUE_SET_SIZE)
on that pipe against keyctl(KEYCTL_SETPERM) on the key from another CPU,
triggering:
BUG: kernel NULL pointer dereference, address: 0000000000000000
RIP: 0010:post_one_notification.isra.0+0xa2/0x1e0
Call Trace:
__post_watch_notification+0x148/0x180
keyctl_setperm_key+0x119/0x130
do_syscall_64+0x108/0x4c0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Kernel panic - not syncing: Fatal exception in interrupt
Fix this by publishing nr_notes last with smp_store_release(), and by
reading it once with smp_load_acquire() in post_one_notification() before
the bitmap and the page array are touched. A poster that observes a
non-zero nr_notes then also observes the pool behind it; one that observes
zero drops the notification as before. |
| In the Linux kernel, the following vulnerability has been resolved:
sched/core: Call wakeup_preempt() for queued tasks during class change
Paul reported recent RCU changes exposed a lost resched where CPU idles
with a rcutorture thread waiting while being completely runnable.
Dumping the rq state at the time of idling with runnable tasks showed
the following:
rq->next_class = &fair_sched_class
rq->nr_running = 1
rq->cfs.h_nr_queued = 0
rq->rt.rt_nr_running = 1
Although the waiting task was an RT task, "rq->next_class" did not point
to rt_sched_class and was stuck at the lower priority fair_sched_class.
Inspecting sched_change_end() revealed the following race with
__sched_setscheduler() for queued, but non-running tasks:
CPU0 CPU1
==== ====
__schedule()
/*
* rq->donor is a fair task that blocks.
* rq->next_class = &fair_sched_class
*/
rq_lock(rq0)
pick_next_task()
/* nr_running = 0 */
pick_task_fair()
sched_balance_newidle()
raw_spin_rq_unlock(rq0)
rq_lock(rq0)
activate_task(rq0, p)
/* p is a fair task */
rq0->nr_running++;
rq0->cfs.h_nr_queued++;
wakeup_preempt(rq, p)
rq->next_class = &fair_sched_class
resched_curr()
rq_unlock(rq0)
__sched_setscheduler(p)
/* p is moved to SCHED_RR */
task_rq_lock(p)
sched_change_begin()
rq0->cfs.h_nr_queued--;
rq0->rt.rt_nr_running++;
sched_change_end()
/*
* p->on_rq = 1 (ctx->queued)
* but p is not rq->donor
* (!ctx->running) hence
* resched_curr() is and
* rq->next_class upgrade is
* skipped.
*/
task_rq_unlock()
raw_spin_rq_lock(rq0)
/*
* rq->nr_running = 1
* rq->cfs.h_nr_queued = 0
* rq->rt.rt_nr_running = 1
* rq->next_class = &fair_sched_class
*/
if (rq->cfs.h_nr_queued && ...)
/* Above is false */
if (rq_modified_above(this_rq, &fair_sched_class))
/* Also false since rq->next_class is still fair */
/*
* sched_balance_newidle() is considered to
* have failed to pull any fair tasks and no
* other wakeups were detected.
*/
return NULL; /* pick_task_fair() */
pick_task_idle()
return rq->idle;
next = rq->idle;
/* Preemption indicators are lost */
clear_tsk_need_resched(prev);
clear_preempt_need_resched();
rq->curr = rq->idle;
!!! rq->idle switches in with rq->running == 1 but !need_resched() !!!
In simple words, enqueue, followed by a class change of the newly queued
task goes unnoticed in rq->next_class indicator and
sched_balance_newidle() sees no fair task, nor any higher priority task
enqueued.
The above sequence will lead to CPU idling with a runnable task on the
CPU.
Call wakeup_preempt() for ctx->queued cases in sched_change_end() to
re-evaluate rq->next_class after class change (ENQUEUE_CLASS) and set
the NEED_RESCHED indicator accordingly.
Newidle balance will correctly see an enqueue of a higher priority
t
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
Drivers: hv: Don't reset VMBus connection state on error/exit paths
In two places, current code forces vmbus_connection.conn_state to
DISCONNECTED prior to calling vmbus_disconnect(). But vmbus_disconnect()
calls vmbus_initiate_unload(), which unloads the VMBus connection
only if the conn_state is CONNECTED. Consequently, the connection
remains and the Hyper-V host might continue to send messages or post
VMBus interrupts.
The problem was introduced in commit 74347a99e73ae ("x86/Hyper-V:
Unload vmbus channel in hv panic callback"), in that
vmbus_initiate_unload() started checking the current connection
state before doing the unload. This commit removed some occurrences
where conn_state was forced to DISCONNECTED, but these two remained,
apparently due to an oversight at the time.
Fix this by not forcing conn_state to DISCONNECTED during VMBus exit,
or if a failure occurs when establishing the connection in the first
place. Whatever value conn_state has at the time is then read by
vmbus_initiate_unload() to determine if there is a connection to
be unloaded. |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: fix NULL deref in tipc_named_node_up() on empty publication list
User-space applications can bind a large number of service addresses to
one or more sockets. Each binding of a local-scope service address inserts
one entry (publication) into the TIPC name table. If the number of these
publications exceeds TIPC_MAX_PUBL (65535), protocol service types
(such as node state and link state) are no longer inserted into the name
table. This causes two issues:
1. User-space applications subscribing to node or link up/down events
stop receiving notifications.
2. A NULL pointer dereference can occur:
BUG: kernel NULL pointer dereference, address: 00000000000000d0
...
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 7.2.0-rc4-default+ #5 PREEMPT(full)
...
RIP: 0010:tipc_named_node_up (./include/linux/skbuff.h:2251 net/tipc/name_distr.c:195 net/tipc/name_distr.c:221)
...
Call Trace:
<IRQ>
tipc_node_write_unlock (net/tipc/node.c:428)
tipc_rcv (net/tipc/node.c:934 net/tipc/node.c:2189)
tipc_udp_recv (net/tipc/udp_media.c:389)
Thread 1 (tipc_net_finalize) | Thread 2 (named_distribute)
-----------------------------|-----------------------------
| ...
| list_for_each_entry(publ, pls, binding_node) {
| ...
| __skb_queue_tail(list, skb);
| ...
| }
| ...
| hdr = buf_msg(skb_peek_tail(list));
... |
tipc_nametbl_publish(); |
If 'tipc_nametbl_publish()' (Thread 1) fails because the number of
local publications reaches TIPC_MAX_PUBL, list (Thread 2) will be empty. As a
result, NULL is passed to 'buf_msg()', leading to a NULL pointer dereference.
Fix these issues by allowing protocol service types (node state, link state,
and topology server) to be inserted into the name table unconditionally.
This ensures that users subscribing to these types always receive
notifications. In addition, the maximum number of local user publications is
reduced to (TIPC_MAX_PUBL - 1). This ensures that the maximum bulk size
calculated in tipc_link_set_queue_limits() remains valid. |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: Dont send random pad bytes in RESET/ACTIVATE messages
The interface name is passed in a fixed length (TIPC_MAX_IF_NAME) buffer.
Replace the strcpy(data, l->if_name) with memcpy() so that the
pad bytes are actually written (l->if_name[] is zero padded)
rather than sending random bytes from the skb to the remote system.
Replace two other strcpy() with strscpy(). |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: sr: restore network header before routing and forwarding
ipv6_srh_rcv() runs with skb->data at the Segment Routing Header (SRH)
while skb_network_header() points at the IPv6 header.
When segments_left > 0, ipv6_srh_rcv() previously restored the skb->data
position by pushing sizeof(struct ipv6hdr), assuming the SRH immediately
followed the fixed IPv6 header. If another extension header (such as a
Hop-by-Hop options header) precedes the SRH, skb_network_offset()
remained negative.
This led to two problems:
1. During ip6_route_input(), fib6_rules_early_flow_dissect() invokes
__skb_flow_dissect() which passes the negative skb_network_offset()
to flow dissection, breaking BPF and C flow dissector logic.
2. If forwarded via ip6_forward() or redirected via act_mirred, downstream
handlers (like sch_fragment() or neighbour output) pass the negative
offset as an unsigned length, triggering OOB memcpy or buffer overflows.
Fix this by pushing -skb_network_offset(skb) before routing, ensuring
skb_network_offset(skb) is 0 for route lookup / flow dissection as well as
downstream forwarding. On the loopback path, pull skb_transport_offset(skb)
to restore skb->data to the SRH before looping back. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: rate limit unmapped SID errors
A client can include many structurally valid but unmapped SIDs in a DACL.
Logging every mapping failure lets one request generate hundreds of kernel
error messages.
Rate limit the message to prevent an authenticated client from flooding
the kernel log. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix listener task lifetime on netdev events
The listener thread exits when its listening socket is shutdown. The
netdevice notifier shuts down the socket before calling kthread_stop(), so
the task_struct can be freed before kthread_stop() gets its reference.
Create the listener in a stopped state and hold an extra task_struct
reference until kthread_stop_put() completes. Also stop and release
listeners before freeing their interface records during TCP teardown. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: btintel: validate version TLV value lengths
btintel_parse_version_tlv() verifies that a complete TLV is present in
the response, but it does not ensure that the value is long enough for
the specific TLV type. A short value can therefore cause an
out-of-bounds read through get_unaligned_le16(), get_unaligned_le32(),
or memcpy().
Reject values shorter than the minimum required by each known TLV type.
Also reject responses that do not contain the Command Complete Status
field. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: btintel: bound firmware ID by TLV length
The firmware ID is treated as a NUL-terminated string even though the
TLV length is its only boundary. If the value does not contain a NUL
terminator, snprintf() can read beyond the received response.
Limit the conversion to the advertised TLV value length. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: SEV: Compute the correct max length of the in-GHCB scratch area
When setting the length of the GHCB scratch area, and the area is in the
GHCB shared buffer, set the effective length of the scratch area to the max
possible size given the start of the guest-provided pointer, and the end of
the shared buffer.
The code was "fine" when first introduced, as KVM doesn't consult the
length of the buffer when emulating MMIO, because the passed in @len always
specifies the *max* size required. But for PSC requests, the incoming @len
is just the minimum length (to process the header), and KVM needs to know
the full size of the scratch area to avoid buffer overflows (spoiler alert).
Opportunistically rename @len => @min_len to better reflect its role. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: SEV: Ignore Port I/O requests of length '0'
Explicitly ignore Port I/O requests of length '0' (or count '0'), so that
setting up the software scratch area (and other code) doesn't have to
worry about underflowing the length, and to allow for WARNing on trying
to configure the scratch area with len==0. |
| In the Linux kernel, the following vulnerability has been resolved:
memfd: deny writeable mappings when implying SEAL_WRITE
When SEAL_EXEC is added, SEAL_WRITE is implied to make W^X. But the
implied seal is set after the check that makes sure the memfd can not have
any writable mappings. This means one can use SEAL_EXEC to apply
SEAL_WRITE while having writeable mappings.
This breaks the contract that SEAL_WRITE provides and can be used by an
attacker to pass a memfd that appears to be write sealed but can still be
modified arbitrarily.
Fix this by adding the implied seals before the call for
mapping_deny_writable() is done. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: fix UAF in iso_recv_frame
iso_recv_frame reads conn->sk under iso_conn_lock but releases the lock
before using sk, with no reference held. A concurrent iso_sock_kill()
can free sk in that window, causing use-after-free on sk->sk_state and
sock_queue_rcv_skb().
Fix by replacing the bare pointer read with iso_sock_hold(conn), which
calls sock_hold() while the spinlock is held, atomically elevating the
refcount before the lock drops. Add a drop_put label so sock_put() is
called on all exit paths where the hold succeeded. |
