| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
perf/core: Fix group leader use-after-free after sibling detach
perf_group_detach() handles leader and sibling detach differently. When the
group leader is detached, all siblings are promoted to singleton events and
their group_leader pointer is reset to themselves. When a sibling is
detached, it is removed from the leader's sibling_list, but its
group_leader pointer is left pointing at the old leader.
That is harmless when the sibling is being closed and freed immediately, as
in the DETACH_DEAD path. It is not safe when the sibling is detached but
kept alive, such as during CPU hotplug with DETACH_GROUP. In that case the
sibling is removed from the context, while its file descriptor can still
keep it alive.
A typical failing sequence is:
- A group contains leader L and sibling S.
- CPU hot-unplug detaches S with DETACH_GROUP, removing it from
L->sibling_list but leaving S->group_leader == L.
- L is later closed and freed.
- A PERF_IOC_FLAG_GROUP ioctl on S follows S->group_leader and
dereferences the freed leader.
This was reproduced by running the perf event fuzzer, CPU hotplug, and a
stress workload concurrently:
Unable to handle kernel paging request at virtual address 006b6b6b6b6b6cdb
CPU: 2 PID: 12489 Comm: perf_fuzzer 6.18.7 PREEMPT
pc : perf_ioctl+0x34c/0xc68
x20: ffffff89a3fa2c70 x8 : 6b6b6b6b6b6b6b6b
Code: 943c4a0e 340047a0 f9404a94 f9411e88 (f940b908)
Call trace:
perf_ioctl+0x34c/0xc68 (P)
__arm64_sys_ioctl+0xa0/0xf4
invoke_syscall+0x58/0xe4
el0_svc_common+0xa8/0xdc
do_el0_svc+0x1c/0x28
el0_svc+0x40/0xc0
el0t_64_sync_handler+0x68/0xdc
el0t_64_sync+0x1c4/0x1c8
The fault happened in perf_ioctl(), where perf_event_for_each() follows
the stale group_leader pointer and perf_event_for_each_child() then
dereferences the freed leader's context.
Fix the use-after-free by promoting the detached sibling to a singleton.
Also fix __event_disable() cgroup accounting and event state change. |
| In the Linux kernel, the following vulnerability has been resolved:
net: smc: fix splice entry lifetime imbalance in smc_rx_splice
smc_rx_splice() passes pages to splice_to_pipe() before taking the
references that cover the lifetime of each splice entry. In the
VM-backed RMB path, splice_to_pipe() may drop unqueued entries through
smc_rx_spd_release(), while queued entries are released later via the
pipe buffer callback.
The old post-splice accounting also derives the number of queued VM pages
from an offset mutated while building the descriptor, and a multi-page
splice pairs one sock_hold() with multiple sock_put() calls.
Take the page and socket references for every candidate entry before
splice_to_pipe(), and drop the matching private state, page reference,
and socket reference from smc_rx_spd_release() for entries that never
get queued. This fixes a refcount imbalance that can underflow page
refcounts and trigger a use-after-free. |
| In the Linux kernel, the following vulnerability has been resolved:
net/dibs: Correct freeing of dmb_clientid_arr
A dibs device interrupt handler can be active after dibs_dev_del() and
may still access dmb_clientid_arr. (UAF)
In case of a failure in dibs_dev_add() being called by dibs_lo_dev_probe()
dmb_clientid_arr is freed twice (double free).
Free dmb_clientid_arr in dibs_dev_release() after last reference is gone.
Note that allocating in dibs_dev_add() instead of dibs_dev_alloc() is ok
for now, because no dmbs can be registered before dibs_dev_add(). |
| In the Linux kernel, the following vulnerability has been resolved:
vxlan: do not arm the ageing timer on a device that is down
vxlan_changelink() arms vxlan->age_timer whenever the requested ageing
interval differs from the configured one:
if (conf.age_interval != vxlan->cfg.age_interval)
mod_timer(&vxlan->age_timer, jiffies);
There is no netif_running() test, so the timer is armed even on a device
that was never brought up. The only synchronous cancel in the driver is
the timer_delete_sync() in vxlan_stop(), which is .ndo_stop.
netif_close_many() drops devices without IFF_UP before
__dev_close_many() runs, so that cancel is skipped for such a device.
vxlan_setup() sets dev->needs_free_netdev = true and age_timer is a
member of struct vxlan_dev, so free_netdev() releases the allocation the
timer lives in while it is still queued on a timer_base.
expire_timers() unlinks the entry before it loads timer->function, so
the timer core writes through the freed object's list pointers:
BUG: KASAN: slab-use-after-free in __run_timers+0x208/0x654
Write of size 8 at addr ffff00001adace68 by task true/192
__asan_store8+0x84/0xac
__run_timers+0x208/0x654
run_timer_softirq+0x154/0x18c
Allocated by task 189:
alloc_netdev_mqs+0x64/0x720
rtnl_create_link+0x4ac/0x520
rtnl_newlink+0x758/0xd00
Freed by task 191:
netdev_release+0x40/0x58
netdev_run_todo+0x4a4/0x8c0
rtnl_dellink+0x200/0x4e8
The rtnl operations involved are netns-scoped, so an unprivileged user
can perform them in a new user and network namespace.
Arming the timer on a down device never had an effect: vxlan_cleanup()
returns early on !netif_running(), and vxlan_open() arms the timer for
any non-zero interval once the device is brought up. Add the missing
test.
Discovered by XBOW, triaged by Baul Lee <baul.lee@xbow.com> |
| In the Linux kernel, the following vulnerability has been resolved:
net: ipv6: clear suppressed fib6 rule result
fib6_rule_suppress() drops a suppressed route with ip6_rt_put_flags(),
but leaves res->rt6 pointing at the released rt6_info.
If no later rule supplies a replacement, fib6_rule_lookup() still sees
res.rt6 and returns that stale dst to its caller. A suppressing rule can
therefore leak a released route back to rt6_lookup(), and the next put
hits rcuref_put_slowpath() from dst_release().
Clear res->rt6 when suppressing the route so suppressed lookups fall
through to the null dst instead of reusing the released one. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: clear iso_data always when detaching conn from hcon
When setting conn->hcon = NULL, also conn->hcon->iso_data = NULL is
necessary, otherwise later iso_conn_free() will UAF.
Fix clearing of iso_data in iso_sock_disconn()
Fixes KASAN: slab-use-after-free in iso_conn_hold_unless_zero on
iso_sock_release() followed by hci_abort_conn_sync(). |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: lock sk in iso_sock_getname
Accessing iso_pi(sk)->conn requires lock_sock, which is not held here.
Fix by adding the lock/release. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: timer: Clear SNDRV_TIMER_IFLG_DEAD once the close completes
snd_timer_close_locked() marks an instance with SNDRV_TIMER_IFLG_DEAD
and returns early when the flag is already set, but the flag is never
cleared again. A completed close ends in remove_slave_links(), which
leaves timeri->timer NULL, so a second close is already harmless through
the timer == NULL path; the early return can only be reached by an
instance that was opened again in between. For such an instance the
close unlinks nothing, so snd_timer_instance_free() frees an object that
is still on timer->open_list_head, still on snd_timer_master_list if it
was opened with a slave key, still owns any adopted slaves, and still
holds its timer and module references.
snd_seq_timer_open() reopens an instance exactly like that: it retries
its fallback open on the same object after a failure that has already
run snd_timer_close_locked() internally. An unprivileged user with
access to /dev/snd/timer and /dev/snd/seq can force that failure, since
snd_timer_check_master() returns -EBUSY when a pending slave matches the
new master's (slave_class, slave_id) key and the target timer has
reached max_instances, and SNDRV_TIMER_IOCTL_SELECT with dev_class =
SNDRV_TIMER_CLASS_SLAVE keeps the caller-supplied dev_sclass, so a
sequencer queue's key can be forged. The freed instance is afterwards
dereferenced by any further snd_timer_open() on that timer, by
snd_timer_check_slave(), and by /proc/asound/timers, which faults on the
stale ti->owner pointer.
The flag only has to be visible while the close is in progress, which is
all its other users need. Clear it in remove_slave_links(), under the
same timer->lock that sets it, once the instance is off every list. |
| In the Linux kernel, the following vulnerability has been resolved:
fou: Fix use-after-free in fou_create()
fou_create() publishes struct fou through sk_user_data before adding the
new FOU port to the per-netns list. If fou_add_to_port_list() fails,
the error path frees fou while it is still reachable through
sk_user_data. A concurrent receive can then dereference the freed
object in fou_from_sock().
This ordering issue was previously noted in the linked discussion.
The failure is reachable when local port 0 is requested. Each socket
binds to a different ephemeral port, but fou_cfg_cmp() compares the
requested port 0 and reports -EALREADY once an entry already exists.
Release the tunnel socket before freeing fou so sk_user_data is cleared
first, and defer reclamation with kfree_rcu() to protect concurrent RCU
readers. This matches the lifetime handling in fou_release(). |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: fix tid_tx use-after-free on BA session stop
ieee80211_stop_tx_ba_cb() hands tid_tx to kfree_rcu() through
ieee80211_remove_tid_tx(), and then reads tid_tx->ndp after dropping
sta->lock:
ieee80211_remove_tid_tx(sta, tid); /* kfree_rcu(tid_tx, rcu_head) */
...
spin_unlock_bh(&sta->lock);
if (start_txq)
ieee80211_agg_start_txq(sta, tid, false);
if (send_delba)
ieee80211_send_delba(..., tid_tx->ndp);
That read is not covered by an RCU read-side critical section, and it runs
in preemptible process context: both callers hold the wiphy mutex, reaching
it either from the ieee80211_ba_session_work() wiphy work or from
ieee80211_sta_tear_down_BA_sessions() during station teardown.
Softirqs can run in that window too, both from the local_bh_enable() that
ends ieee80211_agg_start_txq() and from any interrupt exit, so the RCU
callback can free tid_tx before the read.
Driving the function from a test module with the grace period forced into
that window, KASAN reports the read, and the free arrives on the ordinary
RCU softirq path:
BUG: KASAN: slab-use-after-free in ieee80211_stop_tx_ba_cb+0x3cd/0x400
Read of size 1 at addr ffff888002b9f52e by task kworker/0:1/10
[...]
Freed by task 57:
__kasan_slab_free+0x47/0x70
__rcu_free_sheaf_prepare+0x70/0x250
rcu_free_sheaf_nobarn+0x18/0x40
rcu_core+0x426/0x1310
handle_softirqs+0x144/0x590
__irq_exit_rcu+0xea/0x150
irq_exit_rcu+0x9/0x20
sysvec_apic_timer_interrupt+0x6b/0x80
asm_sysvec_apic_timer_interrupt+0x1a/0x20
send_delba is only set when tx_stop is set, which happens for
AGG_STOP_LOCAL_REQUEST alone, so this is reached on local teardown -
session idle timeout, PTK rekey, suspend, HW reconfig - and not from a
peer's DELBA.
Read ndp into a local before the session is freed, while sta->lock is still
held. tid_tx->ndp has a single writer, in
ieee80211_tx_ba_session_handle_start(), which cannot run concurrently here:
both paths are serialised by the wiphy mutex, and the session is already
marked HT_AGG_STATE_STOPPING at this point. tid_tx->ndp is also the only
tid_tx dereference left after ieee80211_remove_tid_tx() in this function.
[move/change the comment a bit to be more general not just on ndp,
initialize ndp directly] |
| In the Linux kernel, the following vulnerability has been resolved:
mm/huge_memory: unlock i_mmap_rwsem before releasing after-split folios
__folio_split() keeps dereferencing the mapping after the split:
shmem_uncharge(mapping->host) and remap_page() while the folios are still
frozen/locked, and i_mmap_unlock_read(mapping) at the very end, after the
after-split folios have been unlocked and freed.
Nothing holds an inode reference across that. The split relies on @folio
-- which the beyond-EOF drop loop never removes, as it starts at
folio_next(folio) -- staying locked and in the page cache to hold off
eviction. But the unlock loop unlocks @folio before i_mmap_unlock_read()
runs. If the caller's @lock_at is a tail beyond EOF, as memory_failure()
passes when splitting a poisoned tail of a shmem THP that reaches past
i_size during truncation, it too is gone from the page cache; so once
@folio is unlocked no locked, in-cache folio pins the inode, and a
concurrent final iput() can evict and RCU-free it before
i_mmap_unlock_read() touches i_mmap_rwsem:
BUG: KASAN: slab-use-after-free in __up_read+0x634/0x790
i_mmap_unlock_read include/linux/fs.h:537 [inline]
__folio_split+0x732/0x1640 mm/huge_memory.c:4100
try_to_split_thp_page+0xab/0x390 mm/memory-failure.c:1675
memory_failure+0x1394/0x26e0 mm/memory-failure.c:2470
Freed by task 4601:
shmem_free_in_core_inode+0x54/0xb0 mm/shmem.c:5177
evict+0x57f/0xac0 fs/inode.c:870
Do every mapping dereference while @folio still pins the inode: drop
i_mmap_rwsem right after remap_page(), before the loop that unlocks and
frees the after-split folios, and clear @mapping so the exit path does not
unlock it again. shmem_uncharge() and remap_page() already run before
that point, so after this nothing past the unlock loop touches the inode
or the mapping.
This is now a rule the split depends on, alongside keeping @folio frozen
until the page cache is updated: no inode or mapping dereference once the
after-split folios start being unlocked. |
| In the Linux kernel, the following vulnerability has been resolved:
net: openvswitch: fix potential UAF on meter attach failure
While attaching a newly created meter attach_meter() function makes
the new meter visible to other CPUs but can still fail afterwards.
On failure, it detaches the meter back and returns an error.
However, this is an unexpected behavior for the ovs_meter_cmd_set()
that uses a plain kfree(meter) on attach failure without waiting for
RCU readers to stop using it, assuming it was never visible.
This is never a problem for ovs-vswitchd as it always creates meters
before creating any flows that use them. But the UAF can be triggered
with a custom application using uAPI:
BUG: KASAN: slab-use-after-free in ovs_meter_execute (net/openvswitch/meter.c:653)
Read of size 8 at addr ffff88810d152650 by task meter/2508
Call Trace:
ovs_meter_execute (net/openvswitch/meter.c:653)
do_execute_actions (net/openvswitch/actions.c:1407)
ovs_execute_actions (net/openvswitch/actions.c:1584)
ovs_packet_cmd_execute (net/openvswitch/datapath.c:703)
...
netlink_sendmsg (af_netlink.c:1900)
Allocated by task 2519:
__kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415)
ovs_meter_cmd_set (net/openvswitch/meter.c:422)
...
netlink_sendmsg (af_netlink.c:1900)
Freed by task 2519:
kfree (mm/slub.c:2705 mm/slub.c:6405 mm/slub.c:6720)
ovs_meter_cmd_set (net/openvswitch/meter.c:479)
...
netlink_sendmsg (af_netlink.c:1900)
Fix that by making sure attach_meter() doesn't make the meter visible
until all the checks are done and the function can't fail anymore.
This also makes sure the "hash" value is calculated after the potential
re-sizing of the table.
Reported by Trend Micro's Zero Day Initiative as ZDI-CAN-31642. |
| In the Linux kernel, the following vulnerability has been resolved:
i2c: imx: Cancel hrtimer before clearing slave pointer
In i2c_imx_unreg_slave(), the slave pointer is set to NULL after
disabling interrupts. However, a pending interrupt might already
have started the hrtimer (i2c_imx_slave_timeout) before the pointer
was cleared. If the hrtimer fires after i2c_imx->slave is set to
NULL, the timer callback i2c_imx_slave_finish_op() will call
i2c_imx_slave_event() with a NULL slave pointer, which results in a
use-after-free / NULL pointer dereference.
Fix by canceling the hrtimer and waiting for it to complete after
disabling interrupts, before clearing the slave pointer. |
| Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code over a network. |
| Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code over a network. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: seq: midi: Serialize output teardown with event_input
event_process_midi() borrows msynth->output_rfile.output and then
passes the substream to dump_midi() and snd_rawmidi_kernel_write()
without synchronizing with the output open/close transition.
midisynth_use() also publishes output_rfile before
snd_rawmidi_output_params() has finished.
The last midisynth_unuse() can therefore release the same rawmidi file
and free substream->runtime before snd_rawmidi_kernel_write1() takes
its runtime buffer reference. That leaves the event_input path using a
stale substream or runtime and can end in a NULL-deref or use-after-free.
Fix this with two pieces of synchronization. Keep a short IRQ-safe
spinlock only for publishing or clearing output_rfile and for pairing
the output snapshot with an snd_use_lock_t reference. Once
event_process_midi() has taken that in-flight reference, it drops the
spinlock before calling snd_seq_dump_var_event(), dump_midi(), or
snd_rawmidi_kernel_write(). midisynth_unuse() now detaches the visible
rawmidi file under the same spinlock, waits for the in-flight writers
to drain, and only then drains and releases the saved file.
midisynth_use() likewise opens into a local snd_rawmidi_file and
publishes it only after snd_rawmidi_output_params() succeeds.
The buggy scenario involves two paths, with each column showing the
order within that path:
event_input path: last unuse path:
1. event_process_midi() snapshots 1. midisynth_unuse() starts
output_rfile.output. tearing down output_rfile.
2. dump_midi() reaches 2. snd_rawmidi_kernel_release()
snd_rawmidi_kernel_write() closes the output file.
before runtime is pinned. 3. close_substream() frees
3. The callback keeps using substream->runtime.
the borrowed substream.
Validation reproduced this kernel report:
KASAN null-ptr-deref in snd_rawmidi_kernel_write1+0x56/0x360
RIP: 0033:0x7fde7dd0837f
RIP: 0010:snd_rawmidi_kernel_write1+0x56/0x360 |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: use kfree_rcu for offchannel link in mt76_put_vif_phy_link
mt76_put_vif_phy_link() frees the offchannel mlink with plain kfree()
after rcu_assign_pointer(NULL). However, rcu_assign_pointer only prevents
future RCU readers from obtaining the pointer -- it does not wait for
existing readers that already hold it via rcu_dereference.
The TX datapath (e.g. mt7996_mac_write_txwi) dereferences mlink->wcid
and mlink->idx under rcu_read_lock. If a TX softirq obtained the pointer
via rcu_dereference just before the NULL assignment, it will dereference
freed memory after the kfree.
struct mt76_vif_link already contains an rcu_head field that is unused at
this free site -- a developer oversight, since the adjacent
kfree_rcu_mightsleep call for rx_sc in the same function shows the
pattern was understood.
Replace kfree(mlink) with kfree_rcu(mlink, rcu_head). |
| In the Linux kernel, the following vulnerability has been resolved:
net: fib_rules: Don't dump dying fib_rule in fib_rules_dump().
rocker_router_fib_event() calls fib_rule_get() during RCU dump.
If the fib_rule is dying, refcount_inc() will complain about it.
Let's call refcount_inc_not_zero() in fib_rules_dump(). |
| In the Linux kernel, the following vulnerability has been resolved:
net/9p: fix race condition on rdma->state in trans_rdma.c
The rdma->state field is modified without holding req_lock in both
recv_done() and p9_cm_event_handler(), while rdma_request() accesses
the same field under the req_lock spinlock. This inconsistent locking
creates a race condition:
- recv_done() running in softirq completion context sets
rdma->state = P9_RDMA_FLUSHING without acquiring req_lock
- p9_cm_event_handler() modifies rdma->state at multiple points
(ADDR_RESOLVED, ROUTE_RESOLVED, ESTABLISHED, CLOSED) without
req_lock
- rdma_request() uses spin_lock_irqsave(&rdma->req_lock, flags) to
protect the read-modify-write of rdma->state
The race can cause lost state transitions: recv_done() or the CM
event handler could set state to FLUSHING/CLOSED while rdma_request()
is concurrently checking or modifying state under the lock, leading to
the FLUSHING transition being silently overwritten by CLOSING. This
corrupts the connection state machine and can cause use-after-free on
RDMA request objects during teardown.
Fix by adding req_lock protection to all rdma->state modifications in
recv_done() and p9_cm_event_handler(), matching the pattern already
used in rdma_request(). Use spin_lock_irqsave/spin_unlock_irqrestore
in the CM event handler since it can race with recv_done() which runs
in softirq context.
Tested with a kernel module that races two threads (simulating
rdma_request and recv_done/CM handler) on rdma->state with proper
locking: 5.5M+ FLUSHING writes over 27M iterations with 0 lost
transitions. |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: restrict socket queue dumps in enqueue tracepoints
tipc_sk_enqueue() runs with sk->sk_lock.slock held while the socket is
owned by user context. The spinlock protects the backlog queue in this
path, but it does not serialize against the socket owner consuming or
purging sk_receive_queue.
KASAN reported:
CPU: 14 UID: 0 PID: 1050 Comm: tipc3 Not tainted 7.1.0-rc6+ #126 PREEMPT(lazy)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x76/0xa0 lib/dump_stack.c:123
print_report+0xce/0x5b0 mm/kasan/report.c:482
kasan_report+0xc6/0x100 mm/kasan/report.c:597
__asan_report_load4_noabort+0x14/0x30 mm/kasan/report_generic.c:380
tipc_skb_dump+0x1327/0x16f0 net/tipc/trace.c:73
tipc_list_dump+0x208/0x2e0 net/tipc/trace.c:187
tipc_sk_dump+0xaf6/0xd60 net/tipc/socket.c:3996
trace_event_raw_event_tipc_sk_class+0x312/0x5a0 net/tipc/trace.h:188
tipc_sk_rcv+0xb1d/0x1d50 net/tipc/socket.c:2497
tipc_node_xmit+0x1c3/0x1440 net/tipc/node.c:1689
__tipc_sendmsg+0x97a/0x1440 net/tipc/socket.c:1512
tipc_sendmsg+0x52/0x80 net/tipc/socket.c:1400
sock_sendmsg+0x2f6/0x3e0 net/socket.c:825
splice_to_socket+0x7f9/0x1010 fs/splice.c:884
do_splice+0xe21/0x2330 fs/splice.c:936
__do_splice+0x153/0x260 fs/splice.c:1431
__x64_sys_splice+0x150/0x230 fs/splice.c:1616
x64_sys_call+0xeb5/0x2790 arch/x86/entry/syscall_64.c:41
do_syscall_64+0xf3/0x620 arch/x86/entry/syscall_64.c:63
entry_SYSCALL_64_after_hwframe+0x76/0x7e arch/x86/entry/entry_64.S:130
RIP: 0033:0x71624e8aafe2
Code: 08 0f 85 71 3a ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 66 2e 0f 1f 84 00 00 00 00 00 66
RSP: 002b:0000716157ffed68 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 0000716157fff6c0 RCX: 000071624e8aafe2
RDX: 000000000000005f RSI: 0000000000000000 RDI: 0000000000000066
RBP: 0000716157ffed90 R08: 0000000000008000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffff00
R13: 0000000000000021 R14: 0000000000000000 R15: 00007fff89799c40
</TASK>
The TIPC_DUMP_ALL tracepoints in tipc_sk_enqueue() also dump
sk_receive_queue and can therefore dereference skbs that the socket
owner has already dequeued or freed. Restrict these dumps to
TIPC_DUMP_SK_BKLGQ, which matches the queue protected by the held
spinlock.
Keep the change limited to the enqueue path, where the unsafe queue dump
is reachable while the socket is owned by user context. |
