| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/siw: Fix endpoint/socket association handling
Disassociating a socket from an endpoint via siw_socket_disassoc() may
release the last reference on that endpoint and free it. Therefore, don't
clear the endpoints socket pointer after calling that function, but
within.
This fixes a:
BUG: KASAN: slab-use-after-free in siw_cm_work_handler (drivers/infiniband/sw/siw/siw_cm.c:1053 drivers/infiniband/sw/siw/siw_cm.c:1075)
which occurred after processing a malformed MPA request during connection
establishment, causing the new endpoint to be closed. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_core: Fix UAF in hci_unregister_dev()
hci_unregister_dev() does not disable cmd_timer and ncmd_timer
before the hci_dev structure is freed. If a timeout fires
during device teardown, the callback dereferences freed memory
(including the hdev->reset function pointer), leading to a
use-after-free.
Add disable_delayed_work_sync() calls alongside the existing
disable_work_sync() calls to ensure both timers are fully
quiesced before teardown proceeds. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/bnxt_re: Free SRQ toggle page after firmware teardown
Free the toggle page only after firmware teardown completes so that
an NQ interrupt arriving during bnxt_qplib_destroy_srq() won't write
the toggle values to an already-freed page. Move free_page() after
bnxt_qplib_destroy_srq(). |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: fix UAF in cleanup_bearer() due to premature dst_cache_destroy()
TIPC UDP media bearer teardown calls dst_cache_destroy() on its
replicast caches before calling synchronize_net() to wait for
concurrent RCU readers (transmitters) to finish:
static void cleanup_bearer(struct work_struct *work)
{
...
list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
dst_cache_destroy(&rcast->dst_cache);
list_del_rcu(&rcast->list);
kfree_rcu(rcast, rcu);
}
...
dst_cache_destroy(&ub->rcast.dst_cache);
udp_tunnel_sock_release(ub->sk);
synchronize_net();
...
}
This is highly buggy because dst_cache_destroy() immediately frees the
per-CPU cache memory (free_percpu()) and releases the cached dst
entries without any synchronization.
If a concurrent transmitter (e.g., tipc_udp_xmit()) is running on another
CPU under RCU protection, it can call dst_cache_get() concurrently,
leading to:
1. Use-After-Free on the per-CPU cache pointer itself (crash).
2. "rcuref - imbalanced put()" warning if it attempts to release a
dst that was concurrently released by dst_cache_destroy().
Furthermore, calling kfree(ub) immediately after synchronize_net() without
closing the socket first (or waiting after closing it) leaves a window
where a concurrent receiver (tipc_udp_recv()) could start after
synchronize_net(), access ub, and suffer a UAF when kfree(ub) runs.
To fix this, we must defer dst_cache_destroy() and kfree(ub) until after
we have ensured that no more readers can see the bearer/socket and all
existing readers have finished:
1. Defer rcast entry destruction (both dst_cache_destroy() and kfree())
to an RCU callback using call_rcu_hurry().
Using call_rcu_hurry() ensures the dst entries are released quickly.
2. Release the bearer socket using udp_tunnel_sock_release() (stops
new receive readers).
3. Call synchronize_net() to wait for all outstanding RCU readers
(both transmit and receive) to finish.
4. Now that it is safe, call dst_cache_destroy() on the main bearer
cache, and free ub.
Note: 3) and 4) can be changed later in net-next to also use
call_rcu_hurry() and get rid of the synchronize_net() latency. |
| In the Linux kernel, the following vulnerability has been resolved:
bna: prevent IOC timer rearm during teardown
bna: prevent IOC timer rearm during teardown
bnad_pci_remove() and the probe disable_ioceth path call
timer_delete_sync() for ioc_timer, sem_timer and hb_timer, but not for
iocpf_timer. bnad_iocpf_timeout() then takes bnad->bna_lock after
free_netdev() has freed the struct bnad.
Deleting iocpf_timer last does not fix this. sem_timer and
iocpf_timer rearm each other: bnad_iocpf_sem_timeout() can arm
iocpf_timer, and bnad_iocpf_timeout() arms sem_timer from
bfa_ioc_hw_sem_get() when the semaphore is busy.
timer_delete_sync() only waits out its own callback.
bnad_ioceth_disable() can time out and leave that callback live.
Shut all four IOC timers down with timer_shutdown_sync() on both
paths, so a later mod_timer() is ignored.
This issue was identified during our ongoing static-analysis research
while reviewing kernel code. |
| In the Linux kernel, the following vulnerability has been resolved:
net: openvswitch: conntrack: fix helper UAF due to extensions realloc
While calling the helpers, a raw pointer to the extensions area is
wired into expectations list:
-> nf_ct_helper()
-> helper->help()
-> nf_ct_expect_related_report()
-> nf_ct_expect_insert()
-> hlist_add_head_rcu(&exp->lnode, &master_help->expectations)
In case the connection is not confirmed yet, more extensions can be
added afterwards with *_ext_add() calls reallocating the extension
space and leaving the now invalid pointer in the expectations list
that is later accessed while removing the expectation.
Make sure that helpers are called at the end after all the other
extensions are already added.
Note that the helper rejection now leaves the mark and labels set,
but that's not different from how the NAT was handled before or how
the mark and the labels were handled on confirmation failure. And
there are no atomicity guarantees provided by the API anyway. |
| In the Linux kernel, the following vulnerability has been resolved:
xfs: fix cursor and pointer handling when recovering iunlink buckets
LOLLM pointed out a bug in xlog_recover_iunlink_bucket:
1. We don't null out prev_ip after releasing it, which can lead to UAF
problems if the inodegc flush call in the loop fails.
at which point I noticed even more bugs:
2. If the inodegc flush inside the loop fails, we also leak @ip.
3. We set prev_agino to agino having already advanced agino, which
results in inodes with i_prev_unlinked set to itself.
4. If we exit the bottom of the loop with prev_ip set, then prev_ip
aliases ip and we also set its i_prev_unlinked to itself.
Bugs 3 and 4 introduce loops into the unlinked list, though these loops
don't surface because we immediately flush each unlinked inode after
loading it.
Fix all of these issues. |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: act_ct: fix helper UAF due to extensions realloc
While calling the helpers, a raw pointer to the extensions area is
wired into expectations list:
-> nf_ct_helper()
-> helper->help()
-> nf_ct_expect_related_report()
-> nf_ct_expect_insert()
-> hlist_add_head_rcu(&exp->lnode, &master_help->expectations)
In case the connection is not confirmed yet, more extensions can be
added afterwards with *_ext_add() calls reallocating the extension
space and leaving the now invalid pointer in the expectations list
that is later accessed while removing the expectation.
Make sure that helpers are called at the end after all the other
extensions are already added.
Note that the helper rejection now leaves the mark and labels set,
but that's not different from how the NAT was handled before or how
the mark and the labels were handled on confirmation failure. And
there are no atomicity guarantees provided by the API anyway. |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: act_ct: avoid modifying shared unconfirmed ct entry
In a case where skb with an unconfirmed ct entry gets cloned, we may
end up processing both again but with different sets of extensions.
The series of events:
1. The first clone wants to commit and runs the helpers wiring up
the extension pointer into the expectation list.
2. Then it looses the confirmation keeping the entry unconfirmed.
3. Second clone now wants to commit labels or run NAT and adds the
new extension for that breaking the pointer in the expectation
list causing UAF on the destruction path later.
While this is possible to trigger, there should be no practical
network pipeline where we need to process both clones without
modifications in the same zone. So, let's just reset the entry in
case for some reason we got an skb with a shared one. This doesn't
affect any known use cases, but avoids any potential problems with
sharing and modification of the unconfirmed ct entry.
Unlike openvswitch module, act_ct allows for NAT without commit.
Changing that would be a uAPI break. So, act_ct needs to reset on NAT
regardless of the commit flag to avoid reallocation of the extension
space. This, however, doesn't really change the picture for sensible
networking cases as there should be no need to run the same packet
twice (before and after the clone) through conntrack without packet
header or zone changes and without commit.
The fixes tag points to the introduction of helpers, since that's the
main UAF trigger for the sharing. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: take commit root semaphore when iterating in mark_block_group_to_copy()
mark_block_group_to_copy() iterates over the commit root with
skip_locking=true. A concurrent transaction commit can swap and free
the commit root during iteration, causing use-after-free when
accessing extent buffers.
Fix it by using path->need_commit_sem to protect the commit root search. |
| In the Linux kernel, the following vulnerability has been resolved:
hwmon: (pwm-fan) Stop RPM timer before freeing tach data
sample_timer() rearms the RPM timer and accesses the devm-managed
ctx->tachs and ctx->pulses_per_revolution arrays. The cleanup action
which stops the timer is registered before those arrays are allocated.
Since devres releases entries in reverse order, driver detach can free
the arrays before pwm_fan_cleanup() shuts down the timer. A timer expiry
in that window accesses the freed tach data.
With a KASAN kernel, a test-only kprobe delayed entry to
pwm_fan_cleanup() while normal sysfs unbind ran. Each of three runs
reported three four-byte reads and two four-byte writes in sample_timer()
after its backing devm allocations had been freed. The helper did not
invoke the timer callback, cleanup actions or free functions.
With the fix, three matching unbind runs completed without KASAN, BUG,
WARNING, Oops or panic. Instrumentation confirmed that timer retirement
completed before the first timer backing allocation was released.
Split timer retirement from the power cleanup and register its devres
action after the timer backing data and IRQ actions are installed. This
preserves the early power rollback action while ensuring the timer is
retired before its backing data is released. Use timer_shutdown_sync()
because the callback can rearm itself. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: wcn36xx: Fix potential use-after-free in TX ack timer teardown
wcn36xx_dxe_deinit() tears down the TX ack timer with timer_delete(),
which only dequeues the timer and does not wait for a callback that is
already executing; the preceding free_irq() calls synchronize the
interrupt handlers only. The callback, wcn36xx_dxe_tx_timer(), can
therefore be running past the teardown and use the wcn freed along
with the ieee80211_hw in wcn36xx_remove(): it takes wcn->dxe_lock,
reads wcn->tx_ack_skb and passes wcn->hw to
ieee80211_tx_status_irqsafe().
Fix this by using timer_shutdown_sync(), which waits for a running
callback and also prevents the timer from being rearmed again. The
timer is set up again by wcn36xx_dxe_init() on the next start, so the
start/stop cycle is unaffected.
This issue was found by an in-house static analysis tool. |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix use-after-free of iface in cifs_try_adding_channels()
cifs_try_adding_channels() iterates ses->iface_list with
list_for_each_entry_safe_from(), which captures the next entry
(niface) under iface_lock. The loop body then drops iface_lock for
the whole duration of cifs_ses_add_channel().
A concurrent interface refresh (SMB3_request_interfaces() ->
parse_server_interfaces()) marks all ifaces inactive and removes and
frees any that are not re-advertised via list_del() + kref_put(),
where release_iface() is a bare kfree(). Since niface typically has
no channel holding a reference, the list reference is its last and it
can be freed inside the unlocked window. On continue, the iterator
advance step then dereferences niface->iface_head.next, and the loop
body reads iface->rdma_capable/is_active, both on freed memory.
Fix this by never keeping an unreferenced list pointer across the
unlocked window. Each channel attempt now re-scans the list from the
head under iface_lock, takes a kref on the selected candidate, and
passes only that referenced candidate to cifs_ses_add_channel().
weight_fulfilled still tracks selection progress, so restarting the
scan preserves the original weighted distribution and the
weight_fulfilled-before-kref_put ordering on the failure path.
Add a per-pass attempts cap so a flapping interface refresh cannot
keep the inner loop spinning within a single tries increment. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Check ancestor frames for rbtree callbacks
bpf_rbtree_add() invokes its comparator while the caller holds the root
lock. The native insertion code retains raw parent and link pointers across
the callback, so the verifier prohibits unlocking, consuming tree nodes,
or changing RCU state from that callback.
in_rbtree_lock_required_cb() only checks the innermost verifier frame.
Static subprogram calls are permitted while holding a spin lock, and such a
call pushes a frame without in_callback_fn set. Consequently, all callback
restrictions disappear in the nested frame. The subprogram can unlock the
tree, remove and drop the node being compared, then relock. Native insertion
resumes with the stale parent pointer and links freed memory into the tree.
Walk all active frames for the rbtree callback instead. Benign static
subprograms remain permitted, while callback restrictions follow execution
into nested frames. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Preserve inner map identity in callback frames
Callback frame constructors initialize map-typed argument registers with
__mark_reg_known_zero() and then restore map_ptr. This clears map_uid,
which is the only field distinguishing inner maps that share an
inner_map_meta template.
When a timer callback invokes bpf_for_each_map_elem() on a second inner
map, both the saved first map and the second map value can reach the nested
callback as the same template with map_uid zero. bpf_timer_init() then
accepts pairing the timer from the second map with the first map.
The runtime records the first map in the timer without taking a reference.
Freeing that map does not find the timer stored in the second map, so a
later timer callback dereferences the freed map.
Copy map_uid from the same caller register as map_ptr when constructing
for-each, timer/workqueue, and task-work callback arguments. The existing
identity check can then reject mismatched inner maps while allowing a
callback value to be paired with its actual map. |
| In the Linux kernel, the following vulnerability has been resolved:
vhost-vdpa: protect config_ctx from being freed under the config callback
vhost_vdpa_config_cb() loads v->config_ctx and signals it without taking
a reference and without holding any lock:
struct eventfd_ctx *config_ctx = v->config_ctx;
if (config_ctx)
eventfd_signal(config_ctx);
VHOST_VDPA_SET_CONFIG_CALL replaces that field and drops what is normally
the last reference to the old context:
swap(ctx, v->config_ctx);
if (ctx)
eventfd_ctx_put(ctx);
eventfd_ctx_put() drops the last kref and frees the context immediately,
with no RCU grace period, so a callback that has already loaded the
pointer goes on to dereference freed memory. The two sides share no
lock: the ioctl runs under vhost_dev.mutex, while the parent invokes the
callback from its own interrupt or workqueue context.
This is not the reopen refcount underflow fixed by commit f6bbf0010ba0
("vhost-vdpa: fix use-after-free of v->config_ctx"), which was about
vhost_vdpa_config_put() leaving a stale pointer behind. Here the pointer
is maintained correctly and it is the read side that is unprotected.
With VDUSE as the parent this is reachable from userspace with access to
/dev/vduse (root by default). VDUSE_DEV_INJECT_CONFIG_IRQ queues
dev->inject, and vduse_dev_irq_inject() runs the callback under VDUSE's
own dev->irq_lock, which vhost does not hold. vduse_dev_reset() does
flush_work(&dev->inject), but VHOST_VDPA_SET_CONFIG_CALL never goes
through reset, so an inject already in flight is not waited for. A
process that injects config interrupts on the VDUSE fd while another
thread swaps the call fd on the vhost-vdpa fd hits it in seconds:
BUG: KASAN: slab-use-after-free in native_queued_spin_lock_slowpath
Read of size 4 at addr ffff888107d21808 by task kworker/u17:1/2993
Workqueue: vduse-irq vduse_dev_irq_inject
Call Trace:
native_queued_spin_lock_slowpath+0x97/0x5b0
_raw_spin_lock_irqsave+0xd4/0xe0
eventfd_signal_mask+0x69/0x120
vhost_vdpa_config_cb+0x34/0x50
vduse_dev_irq_inject+0x46/0x60
process_one_work+0x468/0x950
Allocated by task 2992:
do_eventfd+0x50/0x200
__x64_sys_eventfd2+0x2e/0x40
Freed by task 2992:
eventfd_ctx_put+0xb9/0xc0
vhost_vdpa_unlocked_ioctl+0x116c/0x2190
Add a spinlock covering every access to config_ctx, so the callback
either signals a context that is still alive or observes NULL, and the
put happens only once no callback can reach the old value.
Clearing the parent's callback before the put would not be enough: of the
in-tree set_config_cb() implementations only VDUSE takes a lock, the rest
store the pointer unlocked, so that would not order against an in-flight
invocation. |
| In the Linux kernel, the following vulnerability has been resolved:
eth: ice: don't dereference pointers from TP_printk()
After forwarding net-next during the v7.3 merge window we started
seeing:
TRACE EVENT ERROR: Event ice_tx_dim_work has double dereference in TP_printk: REC->q_vector->tx.tx_ring->q_index
WARNING: kernel/trace/trace_events.c:420 at test_double_dereference.cold+0x39/0x4b
this is due to extra checks added in tracing subsystem in
commit b5cc230af5e5 ("tracing: Warn when an event dereferences a pointer in TP_printk()").
Printing happens long after the event was recorded, by which point
the pointers may be invalid (the ring or the dim instance).
Copy the eight scalars into the event instead. |
| In the Linux kernel, the following vulnerability has been resolved:
perf/core: Allow list_del during perf_event_overflow()
A PMU might use perf_sched_cb_inc() and perf_sched_cb_dec()
interface to get the PMU call back function pmu::sched_task
invoked at schedule in and schedule out. This is achieved
by walking along the list anchored by sched_cb_list.
The following scenario might lead to a list corruption.
perf_pmu_sched_task()
for_each_list_entry(..., &sched_cb_list)
+--> __perf_pmu_sched_task()
+--> event->pmu->sched_task())
+--> PMU_push_sample()
+--> perf_event_overflow()
+--> __perf_event_overflow()
+--> pmu->stop()
+--> perf_sched_cb_dec()
remove entry from sched_cb_list
while list node in use.
This happens when ioctl(fd, PERF_EVENT_IOC_REFRESH, xxx) has been
invoked and perf_event::event_limit hits zero.
Prevent the list corruption and convert for_each_list_entry()
to for_each_list_entry_safe(). |
| In the Linux kernel, the following vulnerability has been resolved:
configfs: pin the symlink target's dirent instead of chasing ->ci_dentry
create_link() reads the target's configfs_dirent from
item->ci_dentry->d_fsdata, relying on the item reference taken by
get_target(). That reference pins the item, not its dentry: the dentry is
pinned by DCACHE_PERSISTENT, which configfs_remove_dir() releases via
simple_rmdir() while the item is still alive. A symlink racing with rmdir
of its target can therefore find ->ci_dentry freed and its dirent
released, triggering WARN_ON(!atomic_read(&sd->s_count)) in configfs_get().
Take the dirent in get_target() as well, under ->d_lock and atomically
with the item reference, and pass it down to create_link(). A hashed
dentry has not been killed yet, so its ->d_fsdata reference keeps the
dirent alive there. |
| In the Linux kernel, the following vulnerability has been resolved:
configfs: unhash the dentry before dropping the item in rmdir
configfs_get_config_item() treats a hashed dentry as proof that
sd->s_element is a live config_item. configfs_rmdir() breaks that:
simple_rmdir() leaves the dentry hashed, the last reference to the item is
dropped right after, and the dentry is only unhashed by d_delete() once
->rmdir() has returned. configfs_symlink() resolves its target holding no
lock on it, so get_target() can land in that window:
BUG: KASAN: slab-use-after-free in config_item_get+0x26/0x90
get_target fs/configfs/symlink.c:128 [inline]
configfs_symlink+0x4ab/0x1030 fs/configfs/symlink.c:185
Unhash in configfs_remove_dir(), while the item is still guaranteed to be
there. A reference obtained just before that stays harmless, as
create_link() rechecks CONFIGFS_USET_DROPPING, already set by
configfs_detach_prep(). Both configfs_unregister_subsystem() paths
d_drop() after detaching, so this only makes rmdir match them. |
