| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
binfmt_misc: don't let an 'F' entry pin its own instance
An entry registered with 'F' opens its interpreter at registration time
and holds that file until the entry is freed. Any entry nobody removes
by hand only gets closed once the binfmt_misc superblock is shut down.
If the interpreter lives on a mount that keeps that superblock alive the
two pin each other:
binfmt_misc sb -> inode -> entry -> interp_file -> vfsmount -> binfmt_misc sb
TL;DR the file is never closed. Once the mount namespace is gone there
is nothing left to unregister through either.
There are two ways to trigger this bug:
- Point the interpreter at the instance itself. Its files are regular
files owned by the mounter and both bm_get_inode() and
simple_fill_super() leave i_op at empty_iops. So notify_change() falls
back to simple_setattr() and chmod +x works. We never set SB_I_NOEXEC
and so open_exec() accepts it.
- Use the instance as an overlayfs lower layer. The overlay superblock
holds a clone_private_mount() of every layer until it is destroyed and
that clone is in no namespace. So umount_tree() never reaches it.
That's a DoS. And it isn't only the superblock that leaks. It pins the
user namespace it was mounted in, so every iteration permanently eats
one of the caller's user namespace charges.
So let's just do the sane thing. SB_I_NOEXEC makes open_exec() fail on
the instance's own files and s_stack_depth makes overlayfs reject the
layer before it ever takes a clone. That also covers the ecryptfs and
fuse passthrough variants. What 'F' promises is unchanged.
The stable tag is narrower than the Fixes tags on purpose. Before
sandboxed mounts this needed global root against the single instance
everyone shares, and the change doesn't apply to those trees anyway.
Note that SB_I_NODEV is implicitly raised for userns mounts but raise it
explicitly here as well. |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: avoid use-after-free in poll trace queue dumps
TIPC socket tracepoints dump queue state through tipc_sk_dump(). Most
queue-dump callsites already serialize that walk under the socket lock or
sk->sk_lock.slock, but tipc_poll() calls trace_tipc_sk_poll(...,
TIPC_DUMP_ALL, ...) without holding either lock.
That lets the poll trace path reach tipc_list_dump() and backlog head/tail
dumping while another context dequeues and frees an skb, leaving the trace
helper dereferencing a stale queue entry.
Stop the unlocked poll trace site from requesting queue dumps. Other queue
dump trace callsites keep their existing output under the locking they
already provide, while poll still emits the event itself without walking
live queue members from an unlocked context. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: ipset: do not update comments from kernel-side hash adds
mtype_resize() copies comment pointers with memcpy(), not the comment
objects themselves. During the window after an entry has been copied but
before the table swap and backlog replay, the old table is still
published for packet-side updates while the replacement-table entry
already holds the same ip_set_comment_rcu pointer.
If xt_SET --add-set ... --exist hits that old entry in this window,
mtype_add() calls ip_set_init_comment() even though packet-side adds
carry no comment payload. That call frees the shared comment through the
old entry, so the replacement-table entry now holds a stale pointer.
When the queued add is replayed on the new table, mtype_add() calls
ip_set_init_comment() again and strlen() dereferences the stale pointer.
Fix this in mtype_add() by skipping ip_set_init_comment() when
ext->target marks a packet-side add. Userspace adds still update
comments, while packet-side adds can no longer free comment storage
shared with a resize copy. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: usb-audio: Fix DMA buffer out-of-bounds write when fill_max is set
When a USB audio endpoint requests full packet transfers via the fill_max
descriptor flag, data_ep_set_params() promotes ep->curpacksize to
ep->maxpacksize. However, maxsize is left at the original sample-rate
derived value.
Since u->buffer_size is allocated as maxsize * packets, the resulting
DMA buffer is far too small for the requested transfer length. When the
USB host controller streams up to curpacksize bytes per packet, it writes
past the end of the buffer via DMA, corrupting kernel heap memory.
Update maxsize to curpacksize when fill_max is set so that the allocated
DMA buffer size matches the actual transfer request size.
[ changed to reassign maxsize only when ep->fill_max is set -- tiwai ] |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: 6fire: Fix UAF at error handling during probe
Although 6fire driver had a few fixes for dealing with the early error
handling during the probe phase, it forgot a pending URB before
freeing the resources, which may lead to a UAF.
This patch addresses it by doing the almost same cleanup procedure
like the normal disconnect phase at the error path. |
| In the Linux kernel, the following vulnerability has been resolved:
dibs: fix use-after-free of dmb_node in loopback attach/detach/unregister
dibs_lo_attach_dmb(), dibs_lo_detach_dmb() and dibs_lo_unregister_dmb()
look up the dmb_node under dmb_ht_lock, drop the lock and only then
operate on the node's refcount. Nothing keeps the node alive across
that window: __dibs_lo_unregister_dmb() removes the node from the hash
table under the write lock and immediately frees it.
A concurrent final put can therefore free the node between the lookup
and the refcount operation:
CPU0 (attach) CPU1 (owner unregisters)
read_lock_bh(&dmb_ht_lock)
find dmb_node (refcnt == 1)
read_unlock_bh(&dmb_ht_lock)
refcount_dec_and_test() 1 -> 0
write_lock_bh(&dmb_ht_lock)
hash_del(&dmb_node->list)
write_unlock_bh(&dmb_ht_lock)
kfree(dmb_node)
refcount_inc_not_zero(&dmb_node->refcnt) <-- use-after-free
The same window exists for the refcount_dec_and_test() calls in the
detach and unregister paths.
Close the race structurally by making hash table membership and the
refcount transitions atomic with respect to each other:
- Perform the final refcount_dec_and_test() and hash_del() in a single
dmb_ht_lock write-side critical section, in both the unregister and
the detach path. Freeing the node still happens after the lock is
dropped, which is safe because a node whose refcount reached zero has
left the hash table and can no longer be found.
- This establishes the invariant that any node found in the hash table
holds at least one reference, and that the final reference can only
be dropped under the write lock. dibs_lo_attach_dmb() can thus take
its reference with a plain refcount_inc() while still holding the
read lock; refcount_inc_not_zero() is no longer needed.
__dibs_lo_unregister_dmb() no longer touches the hash table and is
renamed to dibs_lo_free_dmb() accordingly.
Note: commit cc21191b584c ("dibs: Move data path to dibs layer") moved
the code to its current location; the race was introduced earlier by
commit c3a910f2380f ("net/smc: implement DMB-merged operations of
loopback-ism").
Tested SMC-D via ISM and dibs loopback. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: mpi3mr: Fix potential deadlock in mpi3mr_fault_uevent_emit
mpi3mr_fault_uevent_emit() runs from the fault watchdog and reset paths
where host I/O may already be blocked. GFP_KERNEL allocations here, both
the local kzalloc_obj() and the ones inside kobject_uevent_env() itself,
can trigger reclaim that waits on that blocked I/O and deadlock.
Use memalloc_noio_save()/restore() to cover the whole call instead of
just the local allocation. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: hold sk properly in iso_conn_ready
sk deref in iso_conn_ready must be done either under conn->lock, or
holding a refcount, to avoid concurrent close. conn->sk is currently
accessed without either:
[Task 1] [Task 2]
iso_sock_release
iso_conn_ready
sk = conn->sk
lock_sock(sk)
conn->sk = NULL
lock_sock(sk)
release_sock(sk)
iso_sock_kill(sk)
UAF on sk deref
Fix possible UAF by holding sk refcount in iso_conn_ready(). Also
recheck after lock_sock that the socket is still valid. Adjust locking
so conn->sk is cleared only under lock_sock. |
| In the Linux kernel, the following vulnerability has been resolved:
net: udp_tunnel: fix memory leak in udp_tunnel_nic_unregister()
syzbot reported a memory leak [1] in the UDP tunnel NIC offload code.
When device registration fails (e.g. in register_netdevice()), netdev core
unwinds by sending a single NETDEV_UNREGISTER notification. If work was queued
during NETDEV_REGISTER (utn->work_pending is set), udp_tunnel_nic_unregister()
returns early:
if (utn->work_pending)
return;
Because failed registrations do not enter netdev_wait_allrefs_any(), no
subsequent NETDEV_UNREGISTER rebroadcast will ever occur. As a result, the
struct udp_tunnel_nic allocated in udp_tunnel_nic_alloc() is leaked
permanently.
Fix this by removing the early return. Instead, synchronously cancel any
pending work with cancel_delayed_work_sync() before freeing @utn.
To be able to call cancel_delayed_work_sync() while holding RTNL (the work also
needs RTNL), switch udp_tunnel_nic_device_sync_work() to rtnl_trylock(). If RTNL
is contended, requeue the work with a 1 jiffy delay (via queue_delayed_work())
to prevent high CPU contention while waiting for RTNL lock.
The utn->work_pending bookkeeping is no longer needed and is removed, as
the workqueue core already tracks the pending/running state of the work.
[1]
BUG: memory leak
unreferenced object 0xffff888127d5f840 (size 96):
comm "syz-executor", pid 5806, jiffies 4294942188
backtrace (crc 99fdb6c8):
__kmalloc_noprof+0x3bf/0x550
udp_tunnel_nic_alloc net/ipv4/udp_tunnel_nic.c:756 [inline]
udp_tunnel_nic_register net/ipv4/udp_tunnel_nic.c:833 [inline]
udp_tunnel_nic_netdevice_event+0x804/0xab0 net/ipv4/udp_tunnel_nic.c:931
notifier_call_chain+0x59/0x160 kernel/notifier.c:85
call_netdevice_notifiers_info+0x7d/0xb0 net/core/dev.c:2250
register_netdevice+0xc10/0xeb0 net/core/dev.c:11478 |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: cls_u32: validate offshift to prevent shift-out-of-bounds
u32_change() copies the user-provided tc_u32_sel.offshift (unsigned char,
0-255) into the kernel knode object without bounds validation. When a
packet later hits u32_classify() with TC_U32_VAROFFSET set, it evaluates
`ntohs(offmask & *data) >> offshift` where the left operand is a 16-bit
value promoted to a 32-bit int. Any offshift >= 32 is undefined behavior
per C11 6.5.7p3, triggerable by an unprivileged user via user/network
namespaces.
UBSAN: shift-out-of-bounds in net/sched/cls_u32.c:236:43
shift exponent 32 is too large for 32-bit type int
Fix this by rejecting offshift >= 16 during filter creation in
u32_change(). |
| In the Linux kernel, the following vulnerability has been resolved:
hwmon: (adt7470) Fix divide-by-zero TOCTOU crash in fan speed read
If the fan data becomes 0 between the FAN_DATA_VALID() check and the
FAN_PERIOD_TO_RPM() conversion, it will result in a divide-by-zero crash
due to a race with a concurrent update of the cached fan value.
Fix a TOCTOU issue by reading fan data once. |
| In the Linux kernel, the following vulnerability has been resolved:
xsk: reclaim invalid Tx descriptors in ZC batch path
The zero-copy Tx batch parser stops when it encounters an invalid
descriptor. If this happens after one or more continuation descriptors,
the Tx consumer can be advanced past fragments that are neither submitted
to the driver nor returned to userspace through the completion ring.
A similar problem occurs when a packet exceeds xdp_zc_max_segs. The
descriptors consumed up to the limit are released without completion, and
the remaining continuation descriptors can subsequently be interpreted
as the beginning of another packet.
Parse Tx batches in packet units and distinguish descriptors belonging to
complete valid packets from descriptors consumed while draining an
invalid or oversized packet. Return the former to the driver and append
the latter to the CQ address area so userspace can reclaim their UMEM
frames.
Treat a standalone invalid descriptor as a one-descriptor reclaim-only
packet. Advancing the Tx-ring consumer releases the ring slot, but does
not by itself return ownership of the referenced UMEM frame to userspace.
Once draining starts, continue until the packet's end-of-packet
descriptor is consumed. Preserve the drain state on the socket when EOP
has not yet been supplied, so draining can continue during a later call.
Leave incomplete but otherwise valid packets on the Tx ring.
Shared-UMEM pools using multi-buffer Tx also need packet-framed parsing.
Walk their Tx sockets one packet at a time, preserving the existing
per-socket fairness scheme, instead of using the legacy one-descriptor
fallback. Keep that fallback for shared pools that do not use
multi-buffer Tx. Since the drain state is maintained per socket and both
the singular and shared paths can resume an interrupted drain, changing
the socket list from singular to shared requires no special bind-time
transition.
CQ entries are positional, and drivers may complete only part of the Tx
work returned by xsk_tx_peek_release_desc_batch(). Therefore, reclaim-only
entries cannot be published immediately when earlier driver-visible
descriptors are still outstanding.
Track the number of driver-visible CQ entries preceding the reclaim
entries. Let xsk_tx_completed() publish partial hardware Tx completions,
and publish the reclaim entries only after every earlier Tx descriptor
has completed. Complete a reclaim-only batch immediately when there is no
driver-visible work in front of it, and prevent another Tx batch from
being appended while reclaim entries remain pending.
Also cap batch processing by the size of the pool's temporary descriptor
array, as Tx rings belonging to sockets sharing a UMEM may have different
sizes.
This ensures that every invalid Tx descriptor consumed by the ZC batch
path is either submitted to the driver as part of a valid packet or
returned to userspace without violating CQ completion ordering. |
| In the Linux kernel, the following vulnerability has been resolved:
xsk: drain continuation descs after overflow in xsk_build_skb()
Fix generic xmit path multi-buffer logic when packets are either too big
(count of descriptors exceed MAX_SKB_FRAGS) or an invalid descriptor is
included in fragmented packet. Introduce xdp_sock::drain_cont and act
upon this flag - when it is set, keep on consuming descriptors from
AF_XDP Tx ring and put them directly onto Cq. Previously these
descriptors were silently lost and could never be reached again. |
| In the Linux kernel, the following vulnerability has been resolved:
iommu/iommufd: Fix IOPF group ownership UAF
iopf_group_alloc() links each last-page IOPF group into the generic IOPF
pending list before invoking the domain fault handler.
iommufd_fault_iopf_handler() also queued an accepted group in the
IOMMUFD deliver list without removing it from the generic pending list.
When detach or HWPT replacement drops the device's IOPF reference count
to zero, an IOMMU driver may call iopf_queue_remove_device(). That
function responds to and frees groups through the generic pending list
without removing the same groups from IOMMUFD's deliver list or response
xarray. A later read, response, or cleanup can then access the freed
group and cause a UAF.
Fix this by dequeuing an accepted group from the generic pending list
before IOMMUFD queues it for userspace response.
Make iopf_group_response() send a response regardless of pending-list
membership, so the dequeued group can still be completed by IOMMUFD. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix use-after-free in __close_file_table_ids()
A ksmbd_file can remain alive after logical close while another session
holds a temporary reference obtained through ksmbd_lookup_fd_inode().
ksmbd_close_fd() currently marks the file closed and drops the idr-owned
reference, but leaves the pointer published in the closing session's idr
until the final reference is dropped.
If the foreign holder performs the final ksmbd_fd_put(), __put_fd_final()
supplies the foreign session's file table to __ksmbd_close_fd(). The object
is then freed without being removed from its owner's idr, and the owner
session later dereferences the stale pointer during file-table teardown.
Remove the volatile id from the owner's idr while ksmbd_close_fd() still
holds that table's lock, and clear volatile_id before dropping
the idr-owned reference. A later foreign final put then only performs
physical destruction and cannot remove the object from the wrong table. |
| In the Linux kernel, the following vulnerability has been resolved:
keys: make keyring key-chunk byte order agree with keyring_diff_objects()
keyring_get_key_chunk() loads description bytes into the index chunk low
address first, while keyring_diff_objects() numbers the first differing
bit from the low end and folds the absolute byte index into the level
without removing the inline-prefix offset the level already carries.
The two disagree on byte order and bit position, so the array can be
told two keys first differ at a bit that does not differ in the chunk
the walker uses, letting crafted descriptions collide into one node.
Load the chunk in the order keyring_diff_objects() assumes and drop the
inline-prefix length when folding the byte index into the level. This
only changes the in-memory ordering used to place keys within a keyring;
add, search and read of non-colliding keys are unaffected. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: btintel: Validate length before parsing diagnostics TLV
btintel_diagnostics() accesses tlv->val[0] without first validating
that the diagnostics VSE is long enough to contain that field, so
may cause reading data beyond the received frame.
Fix by validating the length before access. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: fix race of kfree vs kref_get_unless_zero
hci_conn::iso_data is accessed and modified without lock or RCU.
This leads to a race
[Task hdev->workqueue] [Task 2]
iso_recv iso_conn_put(conn)
conn = LOAD hcon->iso_data iso_conn_free(conn)
iso_conn_hold_unless_zero(conn) hcon->iso_data = NULL
kfree(conn)
kref_get_unless_zero(&conn->ref) /* UAF */
and also to races in iso_conn_add() vs. iso_conn_free().
Fix by adding spinlock hci_conn::proto_lock and using it to guard
hci_conn::iso_data. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: avoid deadlocks in iso_sock_timeout
iso_sock_timeout() takes lock_sock, so sync disabling the timer while
holding that lock may deadlock.
iso_sock_timeout() may also run concurrently with iso_conn_del(), which
leads to UAF
[Task 1] [Task hdev->workqueue]
iso_sock_timeout iso_conn_del
iso_conn_hold_unless_zero iso_chan_del
`------------> iso_conn_put
caller frees hcon
iso_conn_put
iso_conn_free
conn->hcon->iso_data = NULL; /* UAF */
Fix the deadlock by removing the disable from the lock_sock sections.
Move the timer from iso_conn to iso_pinfo to decouple it from iso_conn
which may need to be freed in lock_sock section. Convert some of the
clear_timer to disable_timer. |
| 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. |
