In the Linux kernel, the following vulnerability has been resolved:
ipmr: account multicast table and route memory
A netadmin in a user+net namespace can create many IPv4 and IPv6
multicast routing tables with MRT_TABLE and MRT6_TABLE. Each unseen
id allocates an mr_table via the shared mr_table_alloc(), links it
into the per-net list, and leaves it until netns teardown. Those
objects were not charged to memcg, so the host unreclaimable slab
grows with the table count.
Account mr_table allocations with GFP_KERNEL_ACCOUNT and mark the
IPv4/IPv6 MFC caches SLAB_ACCOUNT. This matches the established
handling of IP addresses, routes and altern
In the Linux kernel, the following vulnerability has been resolved:
reboot: fix cad_pid use-after-free race
cad_pid is a single kernel-wide struct pid pointer. proc_do_cad_pid()
reads it and passes it to pid_vnr() without protecting the lifetime of
the referenced struct pid. A concurrent writer can replace cad_pid and
drop the final reference to the old struct pid after the reader has
loaded the pointer but before pid_vnr() has finished dereferencing it,
causing a use-after-free.
kill_cad_pid() has the same lifetime race when it passes cad_pid to
kill_pid().
At the time this issue was reported, an unprivileged user could reach the
sysctl
ALSA: us122l: Prevent write upgrades for read mappings
In the Linux kernel, the following vulnerability has been resolved:
ALSA: us122l: Prevent write upgrades for read mappings
The hwdep mmap callback rejects read-buffer mappings that are initially
writable, but leaves VM_MAYWRITE set on mappings created with PROT_READ.
A process that can open the hwdep node O_RDWR can later use mprotect() to
make the mapping writable.
The read allocation begins with struct usb_stream. Its read_size member is
used by the fault handler to decide which pages belong to the read buffer.
The read VMA intentionally remains expandable because pcm_usb_stream uses
mremap() after reading that size. Changing read_size f
ALSA: usbusx2y: fix in04_last array size mismatch with in04_buf
In the Linux kernel, the following vulnerability has been resolved:
ALSA: usbusx2y: fix in04_last array size mismatch with in04_buf
The in04_last array in struct usx2ydev is declared as char[24], but
in04_buf is allocated as sizeof(struct us428_ctls) which is 21 bytes.
In i_usx2y_in04_int(), when ctl_snapshot_last == -2 (initialization
path):
memcpy(usx2y->in04_last, usx2y->in04_buf, sizeof(usx2y->in04_last));
This copies 24 bytes from a 21-byte slab allocation, reading 3 bytes
past the end of the source object.
Introduce a USX2Y_IN04_SIZE constant defined as sizeof(struct
us428_ctls) and use it consistently for the in04_last array,
ALSA: usbusx2y: validate URB actual_length in interrupt callback
In the Linux kernel, the following vulnerability has been resolved:
ALSA: usbusx2y: validate URB actual_length in interrupt callback
i_usx2y_in04_int() processes the interrupt URB data without checking
urb->actual_length. A short transfer from a malfunctioning device
would cause the handler to process uninitialized heap data from the
kmalloc-allocated in04_buf, which is then copied to the mmap-accessible
ctl_snapshot[] array.
Fix by using kzalloc() for in04_buf to zero-initialize the buffer,
and adding an actual_length check to skip processing on short
transfers while still resubmitting the URB.
ufs: create the root dentry after loading cylinder metadata
In the Linux kernel, the following vulnerability has been resolved:
ufs: create the root dentry after loading cylinder metadata
ufs_fill_super() installed sb->s_root before it loaded the cylinder
group structures for a writable mount:
sb->s_root = d_make_root(inode);
...
if (!sb_rdonly(sb))
if (!ufs_read_cylinder_structures(sb))
goto failed;
When ufs_read_cylinder_structures() failed, the error path freed the
in-core superblock information and set sb->s_fs_info to NULL while
sb->s_root stayed installed. get_tree_bdev() then reached
deactivate_locked_super(), and because s_root was present,
generic_shutdown_super() called sync_file
ufs: validate cylinder group metadata before caching it
In the Linux kernel, the following vulnerability has been resolved:
ufs: validate cylinder group metadata before caching it
ufs_read_cylinder() copies the cylinder group index and the rotor
positions straight from the on-disk group and caches them without any
check:
ucpi->c_cgx = fs32_to_cpu(sb, ucg->cg_cgx);
ucpi->c_rotor = fs32_to_cpu(sb, ucg->cg_rotor);
ucpi->c_frotor = fs32_to_cpu(sb, ucg->cg_frotor);
ucpi->c_irotor = fs32_to_cpu(sb, ucg->cg_irotor);
They are then used as indices during allocation and free:
- c_cgx indexes the cylinder summary array as
UFS_SB(sb)->fs_cs(ucpi->c_cgx), so a value past s_ncg writes a 32
In the Linux kernel, the following vulnerability has been resolved:
tick/broadcast: Plug clockevents replacement race
朱恺乾 reported and decoded the following race condition when a broadcast
device is replaced:
CPUA CPUB
__tick_broadcast_oneshot_control()
bc = tick_broadcast_device.evtdev;
tick_install_broadcast_device(dev)
clockevents_exchange_device(cur, dev)
shutdown(cur);
detach(cur);
cur->handler = noop;
tick_broadcast_device.evtdev = dev;
tick_broadcast_set_event(bc, next_event); <- FAIL: arms a detached device.
If the original broadcast device has a restricted interrupt affi
ASoC: sti: initialize IRQ lock before requesting IRQ
In the Linux kernel, the following vulnerability has been resolved:
ASoC: sti: initialize IRQ lock before requesting IRQ
uni_reader_init() registers the shared IRQ before initializing
reader->irq_lock. A pending interrupt can invoke the handler while the
lock is still uninitialized.
Initialize the lock before registering the IRQ so the interrupt path
always sees valid lock state.
Bluetooth: btqcomsmd: destroy RPMsg endpoints before freeing hci_dev
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: btqcomsmd: destroy RPMsg endpoints before freeing hci_dev
The command and ACL RPMsg endpoints store struct btqcomsmd as their
callback private data. The receive callbacks dereference btq->hdev
without taking an hci_dev reference.
The current teardown order frees the hci_dev before destroying the RPMsg
endpoints in both the hci_register_dev() error path and the driver remove
path. If WCNSS delivers data in that window, the endpoint callback can
run with an already freed hci_dev and pass it to the Bluetooth core.
For qcom_smd endpoints, rpmsg_destroy_ept() closes
cpufreq: zero-initialize policy cpumask before sysfs publication
In the Linux kernel, the following vulnerability has been resolved:
cpufreq: zero-initialize policy cpumask before sysfs publication
cpufreq_policy_alloc() allocates policy->cpus with alloc_cpumask_var(),
i.e. without __GFP_ZERO, unlike the sibling related_cpus and real_cpus
masks. With CONFIG_CPUMASK_OFFSTACK=y the mask is a separate
kmalloc_node() allocation, so its bitmap holds whatever the slab allocator
left behind:
cpufreq_online()
cpufreq_policy_alloc()
alloc_cpumask_var(&policy->cpus) /* bitmap is uninitialized */
kobject_init_and_add() /* policy%u/ appears in sysfs */
cpufreq_policy_online()
cpufreq: initialize policy rwsem before sysfs publication
In the Linux kernel, the following vulnerability has been resolved:
cpufreq: initialize policy rwsem before sysfs publication
cpufreq_policy_alloc() initializes policy->rwsem after
kobject_init_and_add() has created the policy sysfs directory and its
default attributes. A sysfs access can therefore reach a policy callback
before the semaphore has been initialized.
Initialize policy->rwsem before publishing the policy kobject so sysfs
callbacks always see an initialized semaphore.
net/sched: act_api: release all action references on NEWACTION failure
In the Linux kernel, the following vulnerability has been resolved:
net/sched: act_api: release all action references on NEWACTION failure
When a batched RTM_NEWACTION request replaces an existing action,
tcf_idr_check_alloc() takes a temporary reference on it. If a later
action fails to initialize, tcf_action_destroy() uses strict release
semantics to clean up the actions initialized so far. For an action
bound to a filter, the strict check returns -EPERM without dropping
the temporary reference.
This error also makes tcf_action_destroy() return before releasing
subsequent entries. Any new action initialized between the bound
action and t
net: mpls: clear inner_protocol when the last label is popped
In the Linux kernel, the following vulnerability has been resolved:
net: mpls: clear inner_protocol when the last label is popped
skb_mpls_push() records the pre-encapsulation network header once, gated
on !skb->inner_protocol. skb_mpls_pop() never clears that record, so it
outlives the encapsulation it describes.
Open vSwitch can then re-push MPLS onto a packet whose
inner_network_header still points at the older, deeper offset: push a
label, pop every label, recirculate (ovs_flow_key_update() re-derives
key->eth.type and resets network_header, but leaves inner_*), then push
again. ovs_fragment() trusts the record:
skb->network_header =
netfilter: nf_log: unregister loggers before per-net teardown
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_log: unregister loggers before per-net teardown
nf_log_syslog and nfnetlink_log unregister their per-network namespace
operations before unregistering their global logger backends. This
leaves a window where a sysctl or netlink writer can rebind the still-
registered logger after the per-net pre-exit callback cleared the old
selection.
The race looks like this:
CPU 0 CPU 1
---- ----
unregister_pernet_subsys()
nf_log_unset(net, logger)
net->nf.nf_loggers[pf] = NULL
fbdev: vfb: defer cleanup until the last reference
In the Linux kernel, the following vulnerability has been resolved:
fbdev: vfb: defer cleanup until the last reference
FBIOGETCMAP takes a shallow snapshot of info->cmap and performs the
usercopy after dropping info->lock. vfb_remove() frees the colormap
immediately after unregistering the framebuffer, even when an open file
still holds a reference to fb_info. A concurrent driver unbind can
therefore free the colormap while the ioctl copies it to userspace.
KASAN reports:
BUG: KASAN: slab-use-after-free in _copy_to_user
Read of size 512 by task poc/125
_copy_to_user (./include/linux/instrumented.h:129 ./include/linux/uaccess.h:201
ieee802154: 6lowpan: fix NULL dereference in lowpan_newlink
In the Linux kernel, the following vulnerability has been resolved:
ieee802154: 6lowpan: fix NULL dereference in lowpan_newlink
TUNSETLINK allows a TUN device to change its link-layer type to
ARPHRD_IEEE802154 without initializing ieee802154_ptr. lowpan_newlink()
checks only the device type before dereferencing the pointer, so an
RTM_NEWLINK request can trigger a NULL pointer dereference.
Reject devices without ieee802154_ptr along with devices of the wrong type.
In the Linux kernel, the following vulnerability has been resolved:
ieee802154: cc2520: fix FIFOP work use-after-free
The FIFOP interrupt handler queues cc2520_fifop_irqwork. On removal,
cc2520_remove() only flushes the work. The devm-managed FIFOP IRQ
remains active until after ->remove() returns and can queue the work
again after that flush, allowing it to run after the private data is
released.
Disable the work with disable_work_sync() instead of flushing it, so
the handler can no longer queue it once removal begins. Destroy the
buffer mutex last, since the worker and the stop callback invoked
through ieee802154_unregister_hw() both
In the Linux kernel, the following vulnerability has been resolved:
ipv4: fib: bound automatic table ID allocation
fib_empty_table() probes every table ID from 1 until it finds a
free one. IPv4 tables are stored in a 256-bucket hash table, so a
dense set of IDs makes each probe walk a growing hash chain while
RTNL is held.
Automatic table assignment ("ip rule ... table 0") is an IPv4-only
legacy path. Bound the automatically allocated ID to 4096 so the
RTNL hold stays bounded, without changing lookups of explicitly
specified table IDs.
This changes user-visible behavior. A table-0 rule previously
received the lowest free ID in 1..RT_TA
In the Linux kernel, the following vulnerability has been resolved:
ipv6: flowlabel: cap duplicate leases per socket
ipv6_flowlabel_get() allocates an ipv6_fl_socklist entry for every
successful GET. The recheck path for a compatible existing flowlabel
links another lease without applying any lease admission check. Repeated
GET requests for one shareable label can therefore grow a socket's lease
list without bound.
Reject a new unprivileged lease once the socket already holds
FL_MAX_PER_SOCK leases. Check this on the shared recheck path so reuse
of a globally interned label, including the fl_intern() collision path,
is covered as well. New