| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Free reuseport cBPF prog after RCU grace period.
Eulgyu Kim reported the splat below with a repro. [0]
The repro sets up a UDP reuseport group with a cBPF prog and
replaces it with a new one while another thread is sending
a UDP packet to the group.
The reuseport prog is freed by sk_reuseport_prog_free().
bpf_prog_put() is called for "e"BPF prog to destruct through
multiple stages while cBPF prog is freed immediately by
bpf_release_orig_filter() and bpf_prog_free().
If a reuseport prog is detached from the setsockopt() path
(reuseport_attach_prog() or reuseport_detach_prog()),
sk_reuseport_prog_free() is called without waiting for RCU
readers to complete, resulting in various bugs.
Let's defer freeing the reuseport cBPF prog after one RCU
grace period.
Note "e"BPF prog is safe as is unless the fast path starts
to touch fields destroyed in bpf_prog_put_deferred() and
__bpf_prog_put_noref().
[0]:
BUG: KASAN: vmalloc-out-of-bounds in reuseport_select_sock+0xedc/0x1220 net/core/sock_reuseport.c:596
Read of size 4 at addr ffffc9000051e004 by task slowme/10208
CPU: 6 UID: 1000 PID: 10208 Comm: slowme Not tainted 7.0.0-geb7ac95ff75e #32 PREEMPT(full)
Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
<IRQ>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xca/0x240 mm/kasan/report.c:482
kasan_report+0x118/0x150 mm/kasan/report.c:595
reuseport_select_sock+0xedc/0x1220 net/core/sock_reuseport.c:596
udp4_lib_lookup2+0x3bc/0x950 net/ipv4/udp.c:495
__udp4_lib_lookup+0x768/0xe20 net/ipv4/udp.c:723
__udp4_lib_lookup_skb+0x297/0x390 net/ipv4/udp.c:752
__udp4_lib_rcv+0x1312/0x2620 net/ipv4/udp.c:2752
ip_protocol_deliver_rcu+0x282/0x440 net/ipv4/ip_input.c:207
ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:241
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
__netif_receive_skb_one_core net/core/dev.c:6181 [inline]
__netif_receive_skb net/core/dev.c:6294 [inline]
process_backlog+0xaa4/0x1960 net/core/dev.c:6645
__napi_poll+0xae/0x340 net/core/dev.c:7709
napi_poll net/core/dev.c:7772 [inline]
net_rx_action+0x5d7/0xf50 net/core/dev.c:7929
handle_softirqs+0x22b/0x870 kernel/softirq.c:622
do_softirq+0x76/0xd0 kernel/softirq.c:523
</IRQ>
<TASK>
__local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:924 [inline]
__dev_queue_xmit+0x1dd7/0x3710 net/core/dev.c:4890
neigh_output include/net/neighbour.h:556 [inline]
ip_finish_output2+0xca9/0x1070 net/ipv4/ip_output.c:237
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip_output+0x29f/0x450 net/ipv4/ip_output.c:438
ip_send_skb+0x45/0xc0 net/ipv4/ip_output.c:1508
udp_send_skb+0xb04/0x1510 net/ipv4/udp.c:1195
udp_sendmsg+0x1a71/0x2350 net/ipv4/udp.c:1485
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
__sys_sendto+0x554/0x680 net/socket.c:2206
__do_sys_sendto net/socket.c:2213 [inline]
__se_sys_sendto net/socket.c:2209 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2209
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x160/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x415a2d
Code: b3 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6bc31e41e8 EFLAGS: 00000212 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f6bc31e4cdc RCX: 0000000000415a2d
RDX: 0000000000000001 RSI: 00007f6bc31e421f RDI: 0000000000000003
RBP: 00007f6bc31e4240 R08: 00007f6bc31e4220 R09: 0000000000000010
R10: 0000000000000000 R11:
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: act_api: use RCU with deferred freeing for action lifecycle
When NEWTFILTER and DELFILTER are run concurrently it is possible to create a
race with an associated action.
Let's illustrate with CPU0 running NEWTFILTER and CPU1 running DELFILTER:
0: mutex_lock() <-- holds the idr lock
0: rcu_read_lock()
0: p = idr_find(idr, index) <-- action p is valid (RCU protects IDR)
0: mutex_unlock() <-- releases the idr lock
1: refcount_dec_and_mutex_lock() <-- refcnt 1->0, mutex held
1: idr_remove(idr, index) <-- Action removed from IDR
1: mutex_unlock() <-- mutex released allowing us to delete the action
1: tcf_action_cleanup(p); kfree(p) <-- Kfrees p immediately, no deferral
0: refcount_inc_not_zero(&p->tcfa_refcnt) <-- ouch, UAF p points to freed memory
This patch fixes the race condition between NEWTFILTER and DELFILTER by
adding struct rcu_head to tc_action used in the deferral and introducing a
call_rcu() in the delete path to defer the final kfree().
Note: this is a revert of commit d7fb60b9cafb ("net_sched: get rid of tcfa_rcu")
but also modernization/simplification to directly use kfree_rcu().
Let's illustrate the new restored code path:
0: rcu_read_lock()
1: refcount_dec_and_mutex_lock() <-- refcnt 1->0, mutex held
1: idr_remove(idr, index)
1: mutex_unlock()
1: call_rcu(&p->tcfa_rcu, tcf_action_rcu_free) <-- defer kfree after grace period
0: p = idr_find(idr, index)
0: refcount_inc_not_zero(&p->tcfa_refcnt) <-- fails, refcnt already 0
1: rcu_read_unlock() <-- release so freeing can run after grace period
After CPU1 calls idr_remove(), the object is no longer reachable through the IDR.
CPU0's subsequent idr_find() will return NULL, and even if it still held a
stale pointer, the immediate kfree() is now deferred until after the RCU grace
period, so no UAF can occur. |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: anycast: insert aca into global hash under idev->lock
syzbot reported a splat [1]: a slab-use-after-free in
ipv6_chk_acast_addr(), which walks the global inet6_acaddr_lst[] hash
under RCU and dereferences a struct ifacaddr6 that has already been
freed while still linked in the hash, so a later reader walks into a
dangling node.
In __ipv6_dev_ac_inc() the aca is allocated with refcount 1, then
aca_get() bumps it to 2 to keep it alive across the unlocked region.
It is published to idev->ac_list under idev->lock, but
ipv6_add_acaddr_hash() runs after write_unlock_bh(). A concurrent
teardown (ipv6_ac_destroy_dev() from addrconf_ifdown(), under RTNL)
can slip into that window:
CPU0 __ipv6_dev_ac_inc CPU1 ipv6_ac_destroy_dev (RTNL)
------------------------------ ------------------------------------
aca_alloc() refcnt 1
aca_get() refcnt 2
write_lock_bh(idev->lock)
add aca to ac_list
write_unlock_bh(idev->lock)
write_lock_bh(idev->lock)
pull aca off ac_list
write_unlock_bh(idev->lock)
ipv6_del_acaddr_hash(aca)
hlist_del_init_rcu() is a no-op,
aca is not in the hash yet
aca_put() refcnt 2->1
ipv6_add_acaddr_hash(aca)
aca now inserted into the hash
aca_put() refcnt 1->0
call_rcu(aca_free_rcu) -> kfree(aca)
The hash removal becomes a no-op because the insertion has not
happened yet, so once CPU0 inserts and drops the last reference, the
aca is freed while still linked in inet6_acaddr_lst[], and readers
dereference freed memory after the slab slot is reused.
This window opened once RTNL stopped serializing the join path against
device teardown. Move ipv6_add_acaddr_hash() inside the idev->lock
section so the ac_list and hash insertions are atomic with respect to
teardown: a racing remover now either misses the aca entirely or finds
it in both lists.
acaddr_hash_lock is now nested under idev->lock, which is acquired in
softirq context, so switch all acaddr_hash_lock sites to spin_lock_bh()
to avoid the irq lock inversion reported in [2].
[1] https://syzkaller.appspot.com/bug?extid=a01df04303c131efbf3a
[2] https://lore.kernel.org/netdev/6a194ef7.ba3b1513.1890b4.0000.GAE@google.com/ |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind()
rfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock,
but returns the selected listener after dropping that lock without
taking a reference. rfcomm_connect_ind() then locks the listener,
queues a child socket on it, and may notify it after unlocking it.
The buggy scenario involves two paths, with each column showing the
order within that path:
rfcomm_connect_ind(): listener close:
1. Find parent in 1. close() enters
rfcomm_get_sock_by_channel() rfcomm_sock_release().
2. Drop rfcomm_sk_list.lock 2. rfcomm_sock_shutdown()
without pinning parent. closes the listener.
3. Call lock_sock(parent) and 3. rfcomm_sock_kill()
bt_accept_enqueue(parent, unlinks and puts parent.
sk, true).
4. Read parent flags and may 4. parent can be freed.
call sk_state_change().
If close wins the race, parent can be freed before
rfcomm_connect_ind() reaches lock_sock(), bt_accept_enqueue(), or the
deferred-setup callback.
Take a reference on the listener before leaving rfcomm_sk_list.lock.
After lock_sock() succeeds, recheck that it is still in BT_LISTEN
before queueing a child, cache the deferred-setup bit while the parent
is locked, and drop the reference after the last parent use.
KASAN reported a slab-use-after-free in lock_sock_nested() from
rfcomm_connect_ind(), with the freeing stack going through
rfcomm_sock_kill() and rfcomm_sock_release(). |
| In the Linux kernel, the following vulnerability has been resolved:
xfrm: iptfs: fix use-after-free on first_skb in __input_process_payload
__input_process_payload() stores first_skb into xtfs->ra_newskb under
drop_lock when starting partial reassembly, then unlocks and breaks out
of the processing loop. The post-loop check reads xtfs->ra_newskb
without the lock to decide whether first_skb is still owned:
if (first_skb && first_iplen && !defer && first_skb != xtfs->ra_newskb)
Between spin_unlock and this read, a concurrent CPU running
iptfs_reassem_cont() (or the drop_timer hrtimer) can complete
reassembly, NULL xtfs->ra_newskb, and free the skb. The check then
evaluates first_skb != NULL as true, and pskb_trim/ip_summed/consume_skb
operate on the freed skb — a use-after-free in skbuff_head_cache.
Replace the unlocked read with a local bool that records whether
first_skb was handed to the reassembly state in the current call. The
flag is set after the existing spin_unlock, before the break, using the
pointer equality that is stable at that point (first_skb == skb iff
first_skb was stored in ra_newskb). |
| In the Linux kernel, the following vulnerability has been resolved:
xfrm: policy: fix use-after-free on inexact bin in xfrm_policy_bysel_ctx()
Fix the race by pruning the bin while still holding xfrm_policy_lock,
before dropping it. Use __xfrm_policy_inexact_prune_bin() directly since
the lock is already held. The wrapper xfrm_policy_inexact_prune_bin()
becomes unused and is removed.
Race:
CPU0 (XFRM_MSG_DELPOLICY) CPU1 (XFRM_MSG_NEWSPDINFO)
========================== ==========================
xfrm_policy_bysel_ctx():
spin_lock_bh(xfrm_policy_lock)
bin = xfrm_policy_inexact_lookup()
__xfrm_policy_unlink(pol)
spin_unlock_bh(xfrm_policy_lock)
xfrm_policy_kill(ret)
// wide window, lock not held
xfrm_hash_rebuild():
spin_lock_bh(xfrm_policy_lock)
__xfrm_policy_inexact_flush():
kfree_rcu(bin) // bin freed
spin_unlock_bh(xfrm_policy_lock)
xfrm_policy_inexact_prune_bin(bin)
// UAF: bin is freed |
| In the Linux kernel, the following vulnerability has been resolved:
mm/huge_memory: update file PMD counter before folio_put()
__split_huge_pmd_locked() updates the file/shmem RSS counter after
dropping the PMD mapping's folio reference. If folio_put() drops the last
reference, mm_counter_file() can later read freed folio state via
folio_test_swapbacked().
Move the counter update before folio_put(). |
| In the Linux kernel, the following vulnerability has been resolved:
zram: fix use-after-free in zram_bvec_write_partial()
zram_read_page() picks the sync or async backing device read path based on
whether the parent bio is NULL. zram_bvec_write_partial() passes its
parent bio down, so for ZRAM_WB slots the read is dispatched
asynchronously and zram_read_page() returns 0 while the bio is still in
flight. The caller then runs memcpy_from_bvec(), zram_write_page() and
__free_page() on the buffer, leaving the async read to write into a freed
page.
zram_bvec_read_partial() was switched to NULL in commit 4e3c87b9421d
("zram: fix synchronous reads") for the same reason; the write_partial
counterpart was missed. |
| In the Linux kernel, the following vulnerability has been resolved:
memcg: use round-robin victim selection in refill_stock
Harry Yoo reported that get_random_u32_below() is not safe to call in the
nmi context and memcg charge draining can happen in nmi context.
More specifically get_random_u32_below() is neither reentrant- nor
NMI-safe: it acquires a per-cpu local_lock via local_lock_irqsave() on the
batched_entropy_u32 state. An NMI that lands on a CPU mid-update of the
ChaCha batch state and recurses into the random subsystem would corrupt
that state. The memcg_stock local_trylock prevents re-entry on the percpu
stock itself, but cannot protect an unrelated subsystem's per-cpu lock.
Replace the random pick with a per-cpu round-robin counter stored in
memcg_stock_pcp and serialized by the same local_trylock that already
guards cached[] and nr_pages[]. No atomics, no random calls, no extra
locks needed. |
| In the Linux kernel, the following vulnerability has been resolved:
misc: fastrpc: fix use-after-free race in fastrpc_map_create
fastrpc_map_lookup returns a raw pointer after releasing fl->lock. The
caller fastrpc_map_create then calls fastrpc_map_get (kref_get_unless_zero)
on this unprotected pointer. A concurrent MEM_UNMAP can free the map
between the lock release and the kref operation, resulting in a
use-after-free on the freed slab object.
Restore the take_ref parameter to fastrpc_map_lookup so the reference
is acquired atomically under fl->lock before the pointer is exposed to
the caller. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/gem: Try to fix change_handle ioctl, attempt 4
[airlied: just added some comments on how to reenable]
On-list because the cat is out of the bag and we're clearly not good
enough to figure this out in private. The story thus far:
5e28b7b94408 ("drm: Set old handle to NULL before prime swap in
change_handle") tried to fix a race condition between the gem_close and
gem_change_handle ioctls, but got a few things wrong:
- There's a confusion with the local variable handle, which is actually
the new handle, and so the two-stage trick was actually applied to the
wrong idr slot. 7164d78559b0 ("drm/gem: fix race between
change_handle and handle_delete") tried to fix that by adding yet
another code block, but forgot to add the error handling. Which meant
we now have two paths, both kinda wrong.
- dc366607c41c ("drm: Replace old pointer to new idr") tried to apply
another fix, but inconsistently, again because of the handle confusion
- this would be the right fix (kinda, somewhat, it's a mess) if we'd
do the two-stage approach for the new handle. Except that wasn't the
intent of the original fix.
We also didn't have an igt merged for the original ioctl, which is a big
no-go. This was attempted to address off-list in the original bugfix,
and amd QA people claimed the bug was fixed now. Very clearly that's not
the case. Here's my attempt to sort this out:
- Rename the local variable to new_handle, the old aliasing with
args->handle is just too dangerously confusing.
- Merge the gem obj lookup with the two-stage idr_replace so that we
avoid getting ourselves confused there.
- This means we don't have a surplus temporary reference anymore, only
an inherited from the idr. A concurrent gem_close on the new_handle
could steal that. Fix that with the same two-stage approach
create_tail uses. This is a bit overkill as documented in the comment,
but I also don't trust my ability to understand this all correctly, so
go with the established pattern we have from other ioctls instead for
maximum paranoia.
- Adjust error paths. I've tried to make the error and success paths
common, because they are identical except for which handle is removed
and on which we call idr_replace to (re)install the object again. But
that made things messier to read, so I've left it at the more verbose
version, which unfortunately hides the symmetry in the entire code
flow a bit.
- While at it, also replace the 7 space indent with 1 tab.
And finally, because I flat out don't trust my abilities here at all
anymore:
- Disable the ioctl until we have the igt situation and everything else
sorted out on-list and with full consensus.
v2:
Sashiko noticed that I didn't handle the error path for idr_replace
correctly, it must be checked with IS_ERR_OR_NULL like in
gem_handle_delete. So yeah, definitely should just the existing paths
1:1 because this is endless amounts of tricky.
Also add the Fixes: line for the original ioctl, I forgot that too. |
| In the Linux kernel, the following vulnerability has been resolved:
net: bcmgenet: fix racing timeout handler
The bcmgenet_timeout handler tries to take down all tx queues when
a single queue times out. This is over zealous and causes many race
conditions with queues that are still chugging along. Instead lets
only restart the timed out queue. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: fix locking in hci_conn_request_evt() with HCI_PROTO_DEFER
When protocol sets HCI_PROTO_DEFER, hci_conn_request_evt() calls
hci_connect_cfm(conn) without hdev->lock. Generally hci_connect_cfm()
assumes it is held, and if conn is deleted concurrently -> UAF.
Only SCO and ISO set HCI_PROTO_DEFER and only for defer setup listen,
and HCI_EV_CONN_REQUEST is not generated for ISO. In the non-deferred
listening socket code paths, hci_connect_cfm(conn) is called with
hdev->lock held.
Fix by holding the lock. |
| In the Linux kernel, the following vulnerability has been resolved:
quota: Fix race of dquot_scan_active() with quota deactivation
dquot_scan_active() can race with quota deactivation in
quota_release_workfn() like:
CPU0 (quota_release_workfn) CPU1 (dquot_scan_active)
============================== ==============================
spin_lock(&dq_list_lock);
list_replace_init(
&releasing_dquots, &rls_head);
/* dquot X on rls_head,
dq_count == 0,
DQ_ACTIVE_B still set */
spin_unlock(&dq_list_lock);
synchronize_srcu(&dquot_srcu);
spin_lock(&dq_list_lock);
list_for_each_entry(dquot,
&inuse_list, dq_inuse) {
/* finds dquot X */
dquot_active(X) -> true
atomic_inc(&X->dq_count);
}
spin_unlock(&dq_list_lock);
spin_lock(&dq_list_lock);
dquot = list_first_entry(&rls_head);
WARN_ON_ONCE(atomic_read(&dquot->dq_count));
The problem is not only a cosmetic one as under memory pressure the
caller of dquot_scan_active() can end up working on freed dquot.
Fix the problem by making sure the dquot is removed from releasing list
when we acquire a reference to it. |
| In the Linux kernel, the following vulnerability has been resolved:
net: usb: rtl8150: fix use-after-free in rtl8150_start_xmit()
syzbot reported a KASAN slab-use-after-free read in rtl8150_start_xmit()
when accessing skb->len for tx statistics after usb_submit_urb() has
been called:
BUG: KASAN: slab-use-after-free in rtl8150_start_xmit+0x71f/0x760
drivers/net/usb/rtl8150.c:712
Read of size 4 at addr ffff88810eb7a930 by task kworker/0:4/5226
The URB completion handler write_bulk_callback() frees the skb via
dev_kfree_skb_irq(dev->tx_skb). The URB may complete on another CPU
in softirq context before usb_submit_urb() returns in the submitter,
so by the time the submitter reads skb->len the skb has already been
queued to the per-CPU completion_queue and freed by net_tx_action():
CPU A (xmit) CPU B (USB completion softirq)
------------ ------------------------------
dev->tx_skb = skb;
usb_submit_urb() --+
|-------> write_bulk_callback()
| dev_kfree_skb_irq(dev->tx_skb)
| net_tx_action()
| napi_skb_cache_put() <-- free
netdev->stats.tx_bytes |
+= skb->len; <-- UAF read
Fix it by caching skb->len before submitting the URB and using the
cached value when updating the tx_bytes counter.
The pre-existing tx_bytes semantics are preserved: the counter tracks
the original frame length (skb->len), not the ETH_ZLEN/USB-alignment
padded "count" value that is handed to the device. Changing that
would be a user-visible accounting change and is out of scope for
this UAF fix. |
| In the Linux kernel, the following vulnerability has been resolved:
Revert "wireguard: device: enable threaded NAPI"
This reverts commit 933466fc50a8e4eb167acbd0d8ec96a078462e9c which is
commit db9ae3b6b43c79b1ba87eea849fd65efa05b4b2e upstream.
We have had three independent production user reports in combination
with Cilium utilizing WireGuard as encryption underneath that k8s Pod
E/W traffic to certain peer nodes fully stalled. The situation appears
as follows:
- Occurs very rarely but at random times under heavy networking load.
- Once the issue triggers the decryption side stops working completely
for that WireGuard peer, other peers keep working fine. The stall
happens also for newly initiated connections towards that particular
WireGuard peer.
- Only the decryption side is affected, never the encryption side.
- Once it triggers, it never recovers and remains in this state,
the CPU/mem on that node looks normal, no leak, busy loop or crash.
- bpftrace on the affected system shows that wg_prev_queue_enqueue
fails, thus the MAX_QUEUED_PACKETS (1024 skbs!) for the peer's
rx_queue is reached.
- Also, bpftrace shows that wg_packet_rx_poll for that peer is never
called again after reaching this state for that peer. For other
peers wg_packet_rx_poll does get called normally.
- Commit db9ae3b ("wireguard: device: enable threaded NAPI")
switched WireGuard to threaded NAPI by default. The default has
not been changed for triggering the issue, neither did CPU
hotplugging occur (i.e. 5bd8de2 ("wireguard: queueing: always
return valid online CPU in wg_cpumask_choose_online()")).
- The issue has been observed with stable kernels of v5.15 as well as
v6.1. It was reported to us that v5.10 stable is working fine, and
no report on v6.6 stable either (somewhat related discussion in [0]
though).
- In the WireGuard driver the only material difference between v5.10
stable and v5.15 stable is the switch to threaded NAPI by default.
[0] https://lore.kernel.org/netdev/CA+wXwBTT74RErDGAnj98PqS=wvdh8eM1pi4q6tTdExtjnokKqA@mail.gmail.com/
Breakdown of the problem:
1) skbs arriving for decryption are enqueued to the peer->rx_queue in
wg_packet_consume_data via wg_queue_enqueue_per_device_and_peer.
2) The latter only moves the skb into the MPSC peer queue if it does
not surpass MAX_QUEUED_PACKETS (1024) which is kept track in an
atomic counter via wg_prev_queue_enqueue.
3) In case enqueueing was successful, the skb is also queued up
in the device queue, round-robin picks a next online CPU, and
schedules the decryption worker.
4) The wg_packet_decrypt_worker, once scheduled, picks these up
from the queue, decrypts the packets and once done calls into
wg_queue_enqueue_per_peer_rx.
5) The latter updates the state to PACKET_STATE_CRYPTED on success
and calls napi_schedule on the per peer->napi instance.
6) NAPI then polls via wg_packet_rx_poll. wg_prev_queue_peek checks
on the peer->rx_queue. It will wg_prev_queue_dequeue if the
queue->peeked skb was not cached yet, or just return the latter
otherwise. (wg_prev_queue_drop_peeked later clears the cache.)
7) From an ordering perspective, the peer->rx_queue has skbs in order
while the device queue with the per-CPU worker threads from a
global ordering PoV can finish the decryption and signal the skb
PACKET_STATE_CRYPTED out of order.
8) A situation can be observed that the first packet coming in will
be stuck waiting for the decryption worker to be scheduled for
a longer time when the system is under pressure.
9) While this is the case, the other CPUs in the meantime finish
decryption and call into napi_schedule.
10) Now in wg_packet_rx_poll it picks up the first in-order skb
from the peer->rx_queue and sees that its state is still
PACKET_STATE_UNCRYPTED. The NAPI poll routine then exits e
---truncated--- |
| A flaw was found in libcap. A local unprivileged user can exploit a Time-of-check-to-time-of-use (TOCTOU) race condition in the `cap_set_file()` function. This allows an attacker with write access to a parent directory to redirect file capability updates to an attacker-controlled file. By doing so, capabilities can be injected into or stripped from unintended executables, leading to privilege escalation. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: fix AMDGPU_INFO_READ_MMR_REG
There were multiple issues in that code.
First of all the order between the reset semaphore and the mm_lock was
wrong (e.g. copy_to_user) was called while holding the lock.
Then we allocated memory while holding the reset semaphore which is also
a pretty big bug and can deadlock.
Then we used down_read_trylock() instead of waiting for the reset to
finish.
(cherry picked from commit 361b6e6b303d4b691f6c5974d3eaab67ca6dd90e) |
| In the Linux kernel, the following vulnerability has been resolved:
drm/msm/dpu: fix mismatch between power and frequency
During DPU runtime suspend, calling dev_pm_opp_set_rate(dev, 0) drops
the MMCX rail to MIN_SVS while the core clock frequency remains at its
original (highest) rate. When runtime resume re-enables the clock, this
may result in a mismatch between the rail voltage and the clock rate.
For example, in the DPU bind path, the sequence could be:
cpu0: dev_sync_state -> rpmhpd_sync_state
cpu1: dpu_kms_hw_init
timeline 0 ------------------------------------------------> t
After rpmhpd_sync_state, the voltage performance is no longer guaranteed
to stay at the highest level. During dpu_kms_hw_init, calling
dev_pm_opp_set_rate(dev, 0) drops the voltage, causing the MMCX rail to
fall to MIN_SVS while the core clock is still at its maximum frequency.
When the power is re-enabled, only the clock is enabled, leading to a
situation where the MMCX rail is at MIN_SVS but the core clock is at its
highest rate. In this state, the rail cannot sustain the clock rate,
which may cause instability or system crash.
Remove the call to dev_pm_opp_set_rate(dev, 0) from dpu_runtime_suspend
to ensure the correct vote is restored when DPU resumes.
Patchwork: https://patchwork.freedesktop.org/patch/710077/ |
| In the Linux kernel, the following vulnerability has been resolved:
net: psp: check for device unregister when creating assoc
psp_assoc_device_get_locked() obtains a psp_dev reference via
psp_dev_get_for_sock() (which uses psp_dev_tryget() under RCU);
it then acquires psd->lock and drops the reference. Before
the lock is taken, psp_dev_unregister() can run to completion:
take psd->lock, clear out state, unlock, drop the registration
reference.
The expectation is that the lock prevents device unregistration,
but much like with netdevs special care has to be taken when
"upgrading" a reference to a locked device. Add the missing
check if device is still alive. psp_dev_is_registered() exists
already but had no callers, which makes me wonder if I either
forgot to add this or lost the check during refactoring... |
