| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| 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:
vsock/virtio: read virtqueues under worker locks
Commit bd50c5dc182b ("vsock/virtio: add support for device
suspend/resume") made the *_run flags transition from false to true when
restore installs replacement virtqueues. The RX, TX and event workers
read their virtqueue before locking and checking the corresponding flag,
so a worker delayed across freeze and restore can observe the replacement
queue's running state while retaining a pointer to the deleted queue.
Read each virtqueue under its mutex after checking the run flag, keeping
the pointer and state in the same queue generation. |
| In the Linux kernel, the following vulnerability has been resolved:
vsock/virtio: avoid refilling the RX queue after teardown
Commit b917507e5ad9 ("vsock/virtio: stop workers during the .remove()")
made the RX worker jump to its common exit when rx_run is clear. That
exit still refills the RX queue when the buffer count is low, so work
queued across virtio_vsock_vqs_del() can add buffers after the virtqueues
have been deleted.
BUG: KASAN: slab-use-after-free in virtqueue_add_sgs
Read of size 4 by task kworker/0:1
Workqueue: virtio_vsock virtio_transport_rx_work
Call Trace:
virtqueue_add_sgs (drivers/virtio/virtio_ring.c:2796)
virtio_vsock_rx_fill (net/vmw_vsock/virtio_transport.c:332)
virtio_transport_rx_work (net/vmw_vsock/virtio_transport.c:701)
process_one_work (kernel/workqueue.c:3314)
worker_thread (kernel/workqueue.c:3478)
kthread (kernel/kthread.c:436)
ret_from_fork (arch/x86/kernel/process.c:158)
ret_from_fork_asm (arch/x86/entry/entry_64.S:245)
...
Freed by task 141:
kfree (mm/slub.c:6566)
vp_del_vq (drivers/virtio/virtio_pci_common.c:259)
vp_del_vqs (drivers/virtio/virtio_pci_common.c:285)
virtio_vsock_freeze (net/vmw_vsock/virtio_transport.c:912)
virtio_device_freeze (drivers/virtio/virtio.c:658)
virtio_pci_freeze (drivers/virtio/virtio_pci_common.c:601)
pci_pm_freeze (drivers/pci/pci-driver.c:1098)
device_suspend (drivers/base/power/main.c:1968)
Kernel panic - not syncing: KASAN: panic_on_warn set ...
Jump to a no-refill exit when rx_run is clear, leaving the normal exit
to replenish a running queue. |
| In the Linux kernel, the following vulnerability has been resolved:
veth: fix skb length accounting after XDP frag adjustment
veth exposes non-linear skb fragments through an xdp_buff. If an XDP
program adjusts the fragment area, veth_xdp_rcv_skb() copies
xdp_frags_size back to skb->data_len but leaves skb->len containing the
old fragment contribution.
After a fragment shrink, this makes skb_headlen() larger than the actual
linear area. In the reproduced UDP receive path, __skb_datagram_iter()
copied 1024 bytes past the actual linear tail to userspace, starting at
struct skb_shared_info. The copied bytes included the affected skb's
nr_frags, xdp_frags_size, and a kernel pointer from
skb_shinfo(skb)->frags[0]. Real packet data was displaced by the same
amount and truncated at the end.
Subtract the old data_len before replacing it and add the new data_len
afterwards, keeping skb->len and skb->data_len synchronized.
Additionally, bpf_xdp_pull_data() can advance data_end while leaving
frags present. The skb is then still non-linear, so the old
__skb_put(skb, off) triggers SKB_LINEAR_ASSERT().
Use skb_set_tail_pointer() and update skb->len explicitly instead,
following bpf_prog_run_generic_xdp(). Unlike __skb_put(),
skb_set_tail_pointer() does not require a linear skb.
A 60000-byte UDP datagram on a veth pair with MTU 64000 was shortened by
1024 bytes from its fragment area. Before the fix, all 10 runs produced
corrupted payloads. After the fix, all 10 runs matched the expected
payload exactly. A forced-tailroom reproducer also exercises
bpf_xdp_pull_data() with frags still present; the old code triggers
SKB_LINEAR_ASSERT(), while this fix passes 10/10 runs. |
| In the Linux kernel, the following vulnerability has been resolved:
tls: rx: restore msg_iter before TLS 1.3 optimistic retry
tls_decrypt_sg() advances msg->msg_iter when it maps user pages for
the optimistic TLS 1.3 zero-copy path. If the decrypted record turns
out not to be unpadded application data, tls_decrypt_sw() retries into
a kernel skb, but leaves the iterator advanced.
The subsequent copy from the skb then writes decrypted bytes again at
a later point in the caller iovecs while recvmsg() reports only the
post-retry length. A TLS peer can trigger this after the receiver
enables TLS_RX_EXPECT_NO_PAD.
Revert the iterator by the number of bytes consumed by the optimistic
mapping before retrying without zero-copy.
Add a selftest which sends a TLS 1.3 control record with
TLS_RX_EXPECT_NO_PAD enabled and verifies that recvmsg() does not
overwrite later iovecs beyond the returned length. |
| In the Linux kernel, the following vulnerability has been resolved:
tls: don't leave a full plaintext sk_msg ring unpushed
When the copy path in tls_sw_sendmsg_locked() adds the fragment that fills
the plaintext sk_msg ring, it does not set full_record, so the record is
left full and unpushed. A later splice() then adds to an already full
ring: sk_msg_page_add() has no fullness check of its own, so sg.end wraps
onto sg.start and the ring appears empty. Fragments added after that
overwrite live entries, and sg.size no longer matches what is reachable
between sg.start and sg.end, so pushing the record runs the scatterwalk off
the end of the scatterlist.
An unprivileged user can trigger this on a loopback TCP socket with the
"tls" ULP attached:
BUG: kernel NULL pointer dereference, address: 0000000000000008
RIP: 0010:memcpy_from_scatterwalk+0x32/0xc0
Call Trace:
skcipher_walk_next+0x1d1/0x2c0
gcm_encrypt_aesni_avx+0x1e9/0x220
bpf_exec_tx_verdict+0x3bb/0x860
tls_sw_sendmsg+0xa1a/0xca0
__sys_sendto+0x1da/0x1f0
Set full_record in the copy path when the ring becomes full, and push a
record that is already full on entry to the sendmsg loop. |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: read le->link under the node lock in tipc_node_link_down()
tipc_node_link_down() caches the link pointer before taking n->lock:
struct tipc_link *l = le->link; /* unlocked */
if (!l)
return;
tipc_node_write_lock(n);
if (!tipc_link_is_establishing(l)) { /* deref l */
...
tipc_link_reset(l); /* write into l */
if (delete) {
kfree(l);
le->link = NULL;
The delete=true caller frees that very object under n->lock, so the lock
does not protect the cached pointer against it:
- CPU A, delete=false: tipc_rcv() on TIPC_LINK_DOWN_EVT, or the link
supervision timer via tipc_node_timeout(), reads l unlocked and then
dereferences it under n->lock;
- CPU B, delete=true: netlink TIPC_NL_BEARER_DISABLE -> bearer_disable()
-> tipc_node_delete_links() -> tipc_node_link_down(n, bearer_id, true)
-> kfree(l).
The link is freed with plain kfree(), not kfree_rcu(), and for UDP bearers
disable_media() only schedules the asynchronous cleanup_bearer() work, so
its synchronize_net() runs after the links are already gone. An in-flight
CPU A that has read l therefore dereferences freed memory once B frees it:
a use-after-free read in tipc_link_is_establishing(), and a use-after-free
write via tipc_link_reset() on the establishing branch.
The following trace was captured on 7.2.0-rc5-00284-gaf39eb111ce6:
BUG: KASAN: slab-use-after-free in tipc_link_is_establishing (net/tipc/link.c:285)
Read of size 4 at addr ffff88802e2aa068 by task swapper/2/0
tipc_link_is_establishing (net/tipc/link.c:285)
tipc_node_link_down (net/tipc/node.c:1076)
tipc_node_timeout (net/tipc/node.c:843)
Allocated by task 9549:
tipc_link_create (net/tipc/link.c:490)
tipc_node_check_dest (net/tipc/node.c:1279)
tipc_disc_rcv (net/tipc/discover.c:252)
tipc_udp_recv (net/tipc/udp_media.c:389)
Freed by task 9549:
tipc_node_link_down (net/tipc/node.c:1084)
tipc_node_delete_links (net/tipc/node.c:1320)
bearer_disable (net/tipc/bearer.c:414)
__tipc_nl_bearer_disable (net/tipc/bearer.c:992)
Move the le->link read inside tipc_node_write_lock(), so it is serialised
against the kfree() in the delete path. A racing teardown now either has
not run yet, and we see a valid link, or has already run, and we see NULL. |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: Fix use-after-free in cifs_try_adding_channels()
cifs_try_adding_channels() takes a temporary reference to an interface
before dropping iface_lock. If cifs_ses_add_channel() fails, it drops
that reference and then increments iface->weight_fulfilled.
A concurrent interface list refresh can remove the list reference while
channel creation is in progress. In that case, the failure-path
kref_put() releases the last reference and frees iface. Updating
weight_fulfilled afterward then accesses freed memory.
Increment weight_fulfilled before dropping the temporary reference,
keeping iface alive for the final access. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: SVM: Serialize accesses to the owner and mirror list with separate lock
Interaction between KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM and
KVM_CAP_VM_COPY_ENC_CONTEXT_FROM can cause two separate issues:
- in sev_migrate_from(), when the destination KVM is a mirror, the mirror
entry is moved from the source's list to the owner's mirror_vms list,
without holding the owner's lock unlike other writers of the owner's
mirror list (sev_vm_copy_enc_context_from(), sev_vm_destroy()).
A concurrent COPY or destroy can race with sev_migrate_from() and
corrupt the list.
- In sev_vm_destroy(), the *owner* is still active and could receive
concurrently a KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM that causes
sev->enc_context_owner to change. In this case the incorrect VM
receives kvm_put_kvm().
The second issue needs particular care because the owner could disappear
altogether (even though the race window is impossibly small) between
reading it and locking it. There is thus no way to perform the checks
under the owner lock without putting struct kvm under SLAB_TYPESAFE_BY_RCU
(which would allow kvm_get_kvm_safe() under RCU critical section).
It is much simpler to just use a global lock, since the critical
sections are so small and the new lock is always a leaf lock. |
| In the Linux kernel, the following vulnerability has been resolved:
eventfs: Fix use-after-free in eventfs_remove_rec()
eventfs_remove_rec() recursively removes the child at the current loop
position. After the recursive call returns, list_for_each_entry() advances
by reading list.next from the removed child.
If free_ei() drops the final reference, release_ei() reuses the list/rcu
union to queue an SRCU callback. The child may be freed before that read.
The eventfs_mutex serializes list updates, but it does not keep the removed
child alive or prevent the SRCU callback from running.
Use list_for_each_entry_safe() to save the next sibling before recursively
removing the current child. |
| In the Linux kernel, the following vulnerability has been resolved:
eventfs: Use children field for rcu head and add memory barriers
When an eventfs inode is freed, it sets ei->is_freed and then uses its
ei->list to add it to the srcu link list as the list field is a union with
the rcu list head. As the ei->list is used to iterate over an SRCU
protected list without taking the eventfs_mutex, there's nothing stopping
the iteration over that list to see the ei->rcu instead of the ei->list
and it will read a corrupt target.
To fix this, change the union of the rcu list head with the children list.
On freeing the eventfs inode, set the is_free and execute a smp_wmb()
before adding the eventfs inode to the SRCU list.
On iteration of the ei->children list, at the start, execute a smp_rmb()
and then read the is_freed of the ei to see if the children list is still
valid. If is_freed is set, then the ei_child read is not valid and the
loop should exit immediately. |
| In the Linux kernel, the following vulnerability has been resolved:
Revert "thermal/drivers/hwmon: Cleanup coding style a bit"
Revert commit 030a48b0f6ce ("thermal/drivers/hwmon: Cleanup coding style
a bit") that introduced a use-after-free into the error path of
thermal_add_hwmon_sysfs() by removing a valid check from it. |
| In the Linux kernel, the following vulnerability has been resolved:
ptp: ocp: Fix board ID over-read
The EEPROM board ID is a fixed 13-byte field and is not guaranteed to
contain a NUL terminator. Passing it directly to
devlink_info_version_fixed_put() treats it as a C string and may read
beyond the field.
Format at most OCP_BOARD_ID_LEN bytes into the existing local buffer
before reporting the ID. Use a precision limit because the snprintf()
output size alone does not bound the source string scan. |
| In the Linux kernel, the following vulnerability has been resolved:
ring-buffer: Use current_context for safe per-CPU buffer swap
The ring_buffer_swap_cpu() function currently checks the per-CPU
committing counter to determine if a buffer is actively being written to
before performing the swap. However, there exists a race window where
this check can be bypassed:
ring_buffer_lock_reserve
cpu_buffer = buffer->buffers[cpu]; // cpu_buffer_a
rb_reserve_next_event
rb_start_commit // inc committing
if (unlikely(READ_ONCE(cpu_buffer->buffer) != buffer)) {...}
__rb_reserve_next
rb_move_tail
rb_end_commit(cpu_buffer); // dec committing => 0
/* interrupt hits here, successfully swaps! */
local_inc(&cpu_buffer->committing);
ring_buffer_unlock_commit
cpu_buffer = buffer->buffers[cpu]; // cpu_buffer_b
rb_commit
rb_end_commit
RB_WARN_ON(cpu_buffer, !local_read(&cpu_buffer->committing))
// triggers warning
The committing counter can temporarily drop to 0 during a single write
operation (within rb_move_tail), creating a window where swap can
succeed even though the write is still in progress. This leads to
inconsistent buffer state and triggers the RB_WARN_ON in rb_commit().
Replace the committing counter check with current_context checks, which
are set at the entry of ring_buffer_lock_reserve() and remain valid
throughout the entire write operation, providing a reliable indicator of
buffer busy state during swap. |
| In the Linux kernel, the following vulnerability has been resolved:
mm/page_table_check: skip special zero mappings
page_table_check_set() and page_table_check_clear() account mappings based
on PageAnon(). Shared zero-page PTEs and huge zero PMDs are special
mappings, but page_table_check can still account them as file-backed
pages.
An unprivileged process can populate enough zero mappings to overflow
file_map_count and hit the existing BUG_ON(). The PTE path can do this
with the shared zero page, and the PMD path can do the same with huge zero
mappings.
Skip special zero mappings in the user page-table accounting paths. Keep
the PTE-side pte_special() check, and identify huge zero PMDs from the
mapped folio instead of pmd_special(). That covers architectures where
pmd_special() is a no-op without adding huge_zero_pfn checks to the
generic counter helpers. |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: fix Route Information option length validation
rt6_route_rcv() validates the Route Information option (RFC 4191) length
against the prefix length, but both checks are off by one.
rinfo->length is the ND option length in units of 8 octets and it
*includes* the 8-byte option header, so an option carrying N bytes of
prefix has length == 1 + N/8. RFC 4191 section 2.3 requires length 3
when Prefix Length is greater than 64, and 2 or 3 when it is greater
than 0. The code accepts length >= 2 and length >= 1 respectively.
ipv6_addr_prefix() then copies prefix_len/8 bytes out of rinfo->prefix,
so a Router Advertisement with (prefix_len=128, length=2) or
(prefix_len=64, length=1) makes the kernel read up to 8 bytes past the
end of the option. Those bytes end up in the prefix of the route that
gets installed, so they are visible to userspace:
# RA with a Route Information option (prefix_len=128, length=2)
# followed by a source link-layer address option, 01 01 de ad be ef ca fe
$ ip -6 route show
2001:db8:dead:beef:101:dead:beef:cafe via fe80::1234 dev veth0 proto ra
^^^^^^^^^^^^^^^^^^ the next option, read out of bounds
When the Route Information option is the last one in the packet, those
eight bytes come from the skb tail room instead.
Reject the option lengths RFC 4191 does not allow. |
| In the Linux kernel, the following vulnerability has been resolved:
ip6_tunnel: clear skb2->cb[] in ip6ip6_err()
ip6ip6_err() clones an outer IPv6 ICMP error skb, pulls it to the
quoted inner IPv6 packet, and then passes the clone to icmpv6_send().
The clone still carries the outer packet's inet6_skb_parm in skb->cb.
If the outer packet had a Home Address Option, IP6CB(skb2)->dsthao
remains non-zero after skb_pull(). icmpv6_send() later calls
mip6_addr_swap(), which uses that stale dsthao offset against the quoted
inner packet. A malformed inner destination-options header can then make
the HAO lookup and address swap run past the end of the quoted packet
and corrupt skb_shared_info.
Clear skb2->cb[] before pulling the quoted inner IPv6 packet so the
reply path does not reuse metadata left by the outer IPv6 stack. |
| In the Linux kernel, the following vulnerability has been resolved:
fs,fsverity: remove check for fsverity being enabled in setattr_prepare()
The check that fs-verity is available in the kernel is not necessary
here. Filesystems could have fsverity files even without fs-verity
enabled. In that case, truncate on fsverity file will succeed, what this
check is trying to prevent. |
| In the Linux kernel, the following vulnerability has been resolved:
sched/psi: Shut down rtpoll_timer in psi_cgroup_free()
psi_schedule_rtpoll_work() is called locklessly from the scheduler hotpath
and can race psi_trigger_destroy() taking down the last rtpoll trigger under
rtpoll_trigger_lock:
psi_schedule_rtpoll_work() psi_trigger_destroy()
rcu_read_lock();
task = rcu_dereference(rtpoll_task);
rcu_assign_pointer(rtpoll_task, NULL);
timer_delete(&rtpoll_timer);
mod_timer(&rtpoll_timer, ...);
rcu_read_unlock();
synchronize_rcu();
kthread_stop(task_to_destroy);
The group can then be freed with the re-armed timer still pending, and
poll_timer_fn() runs on freed memory.
461daba06bdc ("psi: eliminate kthread_worker from psi trigger scheduling
mechanism") deleted the timer synchronously after the synchronize_rcu(),
which prevented this but raced trigger creation instead: the deletion could
cancel the timer that a new trigger set armed during the grace period and,
as creation also reinitialized the timer at the time, corrupt it.
8f91efd870ea ("psi: Fix race between psi_trigger_create/destroy") moved the
initialization into group_init() and the deletion into the locked section,
trading the creation races for the window above.
Neither placement in the destruction path works. A pending timer firing
while the group is alive is harmless though. poll_timer_fn() just wakes the
rtpoll waitqueue and doesn't re-arm itself. Bind the timer to the group's
lifetime instead and shut it down in psi_cgroup_free(). Nothing can arm it
by then. timer_shutdown_sync() because the timer is never armed again. |
| In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Take cgroup_lock() first in scx_cgroup_lock()
scx_cgroup_lock() write-locks scx_cgroup_ops_rwsem and then takes
cgroup_lock(), which can deadlock through kernfs:
scx enable/disable cgroup rmdir cpu.weight write
------------------ ------------ ----------------
cgroup_lock()
percpu_down_write(rwsem)
cgroup_lock()
kernfs_get_active()
percpu_down_read(rwsem)
kernfs_drain()
The enable path waits for the rmdir to release cgroup_mutex. The rmdir,
deactivating the cpu controller's files, waits in kernfs_drain() for the
write's active reference. The write, in scx_group_set_weight(), waits for
the rwsem behind the pending writer.
Take cgroup_lock() first. The set_* paths take no cgroup locks inside the
read side, so a pending write-lock then only waits for read sections that
always run to completion, and no dependency from the rwsem back to
cgroup_mutex remains. |
