| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
net: airoha: fix BQL imbalance in TX path
Fix a possible BQL imbalance in airoha_dev_xmit(), where inflight
packets are accounted only for the AIROHA_NUM_TX_RING netdev TX
queues. The queue index is computed as:
qid = skb_get_queue_mapping(skb) % ARRAY_SIZE(qdma->q_tx)
txq = netdev_get_tx_queue(dev, qid);
However, airoha_qdma_tx_napi_poll() accounts completions across all
netdev TX queues (num_tx_queues), leading to inconsistent BQL
accounting.
Also reset all netdev TX queues in the ndo_stop callback. |
| 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:
neigh: let neigh_xmit take skb ownership
neigh_xmit always releases the skb, except when no neighbour table is
found. But even the first added user of neigh_xmit (mpls) relied on
neigh_xmit to release the skb (or queue it for tx).
sashiko reported:
If neigh_xmit() is called with an uninitialized neighbor table (for
example, NEIGH_ND_TABLE when IPv6 is disabled), it returns -EAFNOSUPPORT
and bypasses its internal out_kfree_skb error path. Because the return
value of neigh_xmit() is ignored here, does this leak the SKB?
Assume full ownership and remove the last code path that doesn't
xmit or free skb. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/xe: Fix error cleanup in xe_exec_queue_create_ioctl()
Two error handling issues exist in xe_exec_queue_create_ioctl():
1. When xe_hw_engine_group_add_exec_queue() fails, the error path jumps
to put_exec_queue which skips xe_exec_queue_kill(). If the VM is in
preempt fence mode, xe_vm_add_compute_exec_queue() has already added
the queue to the VM's compute exec queue list. Skipping the kill
leaves the queue on that list, leading to a dangling pointer after
the queue is freed.
2. When xa_alloc() fails after xe_hw_engine_group_add_exec_queue() has
succeeded, the error path does not call
xe_hw_engine_group_del_exec_queue() to remove the queue from the hw
engine group list. The queue is then freed while still linked into
the hw engine group, causing a use-after-free.
Fix both by:
- Changing the xe_hw_engine_group_add_exec_queue() failure path to jump
to kill_exec_queue so that xe_exec_queue_kill() properly removes the
queue from the VM's compute list.
- Adding a del_hw_engine_group label before kill_exec_queue for the
xa_alloc() failure path, which removes the queue from the hw engine
group before proceeding with the rest of the cleanup.
(cherry picked from commit 37c831f401746a45d510b312b0ed7a77b1e06ec8) |
| In the Linux kernel, the following vulnerability has been resolved:
bonding: 3ad: implement proper RCU rules for port->aggregator
syzbot found a data-race in bond_3ad_get_active_agg_info /
bond_3ad_state_machine_handler [1] which hints at lack of proper
RCU implementation.
Add __rcu qualifier to port->aggregator, and add proper RCU API.
[1]
BUG: KCSAN: data-race in bond_3ad_get_active_agg_info / bond_3ad_state_machine_handler
write to 0xffff88813cf5c4b0 of 8 bytes by task 36 on cpu 0:
ad_port_selection_logic drivers/net/bonding/bond_3ad.c:1659 [inline]
bond_3ad_state_machine_handler+0x9d5/0x2d60 drivers/net/bonding/bond_3ad.c:2569
process_one_work kernel/workqueue.c:3302 [inline]
process_scheduled_works+0x4f0/0x9c0 kernel/workqueue.c:3385
worker_thread+0x58a/0x780 kernel/workqueue.c:3466
kthread+0x22a/0x280 kernel/kthread.c:436
ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
read to 0xffff88813cf5c4b0 of 8 bytes by task 22063 on cpu 1:
__bond_3ad_get_active_agg_info drivers/net/bonding/bond_3ad.c:2858 [inline]
bond_3ad_get_active_agg_info+0x8c/0x230 drivers/net/bonding/bond_3ad.c:2881
bond_fill_info+0xe0f/0x10f0 drivers/net/bonding/bond_netlink.c:853
rtnl_link_info_fill net/core/rtnetlink.c:906 [inline]
rtnl_link_fill+0x1d7/0x4e0 net/core/rtnetlink.c:927
rtnl_fill_ifinfo+0xf8e/0x1380 net/core/rtnetlink.c:2168
rtmsg_ifinfo_build_skb+0x11c/0x1b0 net/core/rtnetlink.c:4453
rtmsg_ifinfo_event net/core/rtnetlink.c:4486 [inline]
rtmsg_ifinfo+0x6d/0x110 net/core/rtnetlink.c:4495
__dev_notify_flags+0x76/0x390 net/core/dev.c:9790
netif_change_flags+0xac/0xd0 net/core/dev.c:9823
do_setlink+0x905/0x2950 net/core/rtnetlink.c:3180
rtnl_group_changelink net/core/rtnetlink.c:3813 [inline]
__rtnl_newlink net/core/rtnetlink.c:3981 [inline]
rtnl_newlink+0xf55/0x1400 net/core/rtnetlink.c:4109
rtnetlink_rcv_msg+0x64b/0x720 net/core/rtnetlink.c:6995
netlink_rcv_skb+0x123/0x220 net/netlink/af_netlink.c:2550
rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:7022
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x5a8/0x680 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x5c8/0x6f0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:787 [inline]
__sock_sendmsg net/socket.c:802 [inline]
____sys_sendmsg+0x563/0x5b0 net/socket.c:2698
___sys_sendmsg+0x195/0x1e0 net/socket.c:2752
__sys_sendmsg net/socket.c:2784 [inline]
__do_sys_sendmsg net/socket.c:2789 [inline]
__se_sys_sendmsg net/socket.c:2787 [inline]
__x64_sys_sendmsg+0xd4/0x160 net/socket.c:2787
x64_sys_call+0x194c/0x3020 arch/x86/include/generated/asm/syscalls_64.h:47
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
value changed: 0x0000000000000000 -> 0xffff88813cf5c400
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 22063 Comm: syz.0.31122 Tainted: G W syzkaller #0 PREEMPT(full)
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 |
| In the Linux kernel, the following vulnerability has been resolved:
net: tls: fix strparser anchor skb leak on offload RX setup failure
When tls_set_device_offload_rx() fails at tls_dev_add(), the error path
calls tls_sw_free_resources_rx() to clean up the SW context that was
initialized by tls_set_sw_offload(). This function calls
tls_sw_release_resources_rx() (which stops the strparser via
tls_strp_stop()) and tls_sw_free_ctx_rx() (which kfrees the context),
but never frees the anchor skb that was allocated by alloc_skb(0) in
tls_strp_init().
Note that tls_sw_free_resources_rx() is exclusively used for this
"failed to start offload" code path, there's no other caller.
The leak did not exist before commit 84c61fe1a75b ("tls: rx: do not use
the standard strparser"), because the standard strparser doesn't try
to pre-allocate an skb.
The normal close path in tls_sk_proto_close() handles cleanup by calling
tls_sw_strparser_done() (which calls tls_strp_done()) after dropping
the socket lock, because tls_strp_done() does cancel_work_sync() and
the strparser work handler takes the socket lock. |
| In the Linux kernel, the following vulnerability has been resolved:
net: ena: PHC: Fix potential use-after-free in get_timestamp
Move the phc->active check and resp pointer assignment to after
acquiring the spinlock. Previously, phc->active was checked without
holding the lock, and resp was cached from ena_dev->phc.virt_addr
before the lock was acquired.
If ena_com_phc_destroy() runs between the lockless active check and
the lock acquisition, it sets active=false, releases the lock, frees
the DMA memory, and sets virt_addr=NULL. The get_timestamp path would
then read a NULL virt_addr and dereference it.
With both the active check and the pointer read under the lock,
destroy cannot free the memory while get_timestamp is using it. |
| In the Linux kernel, the following vulnerability has been resolved:
smb/client: fix possible infinite loop and oob read in symlink_data()
On 32-bit architectures, the infinite loop is as follows:
len = p->ErrorDataLength == 0xfffffff8
u8 *next = p->ErrorContextData + len
next == p
On 32-bit architectures, the out-of-bounds read is as follows:
len = p->ErrorDataLength == 0xfffffff0
u8 *next = p->ErrorContextData + len
next == (u8 *)p - 8 |
| In the Linux kernel, the following vulnerability has been resolved:
ceph: put folios not suitable for writeback
The batch holds references to the folios (see `filemap_get_folios`,
`folio_batch_release`), so we need to `folio_put` the folios we remove.
Tested on v6.18. |
| In the Linux kernel, the following vulnerability has been resolved:
virt: sev-guest: Do not use host-controlled page order in cleanup path
When issuing an extended guest request (SVM_VMGEXIT_EXT_GUEST_REQUEST),
get_ext_report() allocates a buffer to retrieve a certificate blob from the
host, keeping track of its size in report_req->certs_len.
However, the host may return SNP_GUEST_VMM_ERR_INVALID_LEN, indicating
an invalid buffer size, as well as the expected length of such buffer.
get_ext_report() subsequently updates report_req->certs_len with the
host-controlled value, and cleans up the buffer by computing a page order
from such value. This is incorrect, as the host-provided length may not
match the page order of the original allocation, potentially resulting
in corruption in the page allocator.
Fix this by using alloc_pages_exact() instead, and reusing @npages to
compute the size passed to free_pages_exact(). For consistency, also
use @npages to compute the size when allocating the pages, even though
this last change has no functional effect. |
| In the Linux kernel, the following vulnerability has been resolved:
libceph: Fix potential out-of-bounds access in osdmap_decode()
When decoding osd_state and osd_weight from an incoming osdmap in
osdmap_decode(), both are decoded for each osd, i.e., map->max_osd
times. The ceph_decode_need() check only accounts for
sizeof(*map->osd_weight) once. This can potentially result in an
out-of-bounds memory access if the incoming message is corrupted such
that the max_osd value exceeds the actual content of the osdmap message.
This patch fixes the issue by changing the corresponding part in the
ceph_decode_need() check to account for
map->max_osd*sizeof(*map->osd_weight). |
| In the Linux kernel, the following vulnerability has been resolved:
libceph: Fix potential null-ptr-deref in decode_choose_args()
A message of type CEPH_MSG_OSD_MAP contains an OSD map that itself
contains a CRUSH map. When decoding this CRUSH map in crush_decode(), an
array of max_buckets CRUSH buckets is decoded, where some indices may
not refer to actual buckets and are therefore set to NULL. The received
CRUSH map may optionally contain choose_args that get decoded in
decode_choose_args(). When decoding a crush_choose_arg_map, a series of
choose_args for different buckets is decoded, with the bucket_index
being read from the incoming message. It is only checked that the bucket
index does not exceed max_buckets, but not that it doesn't point to an
index with a NULL bucket. If a (potentially corrupted) message contains
a crush_choose_arg_map including such a bucket_index, a null pointer
dereference may occur in the subsequent processing when attempting to
access the bucket with the given index.
This patch fixes the issue by extending the affected check. Now, it is
only attempted to access the bucket if it is not NULL. |
| In the Linux kernel, the following vulnerability has been resolved:
libceph: Fix potential out-of-bounds access in __ceph_x_decrypt()
In __ceph_x_decrypt(), a part of the buffer p is interpreted as a
ceph_x_encrypt_header, and the magic field of this struct is accessed.
This happens without any guarantee that the buffer is large enough to
hold this struct. The function parameter ciphertext_len represents the
length of the ciphertext to decrypt and is guaranteed to be at most the
remaining size of the allocated buffer p. However, this value is not
necessarily greater than sizeof(ceph_x_encrypt_header). E.g., a message
frame of type FRAME_TAG_AUTH_REPLY_MORE, that is just as long to hold
the ciphertext at its end with a ciphertext_len of 8 or less, can
trigger an out-of-bounds memory access when accessing hdr->magic.
This patch fixes the issue by adding a check to ensure that the
decrypted plaintext in the buffer is large enough to represent at least
the ceph_x_encrypt_header. |
| In the Linux kernel, the following vulnerability has been resolved:
libceph: Fix potential out-of-bounds access in crush_decode()
A message of type CEPH_MSG_OSD_MAP containing a crush map with at least
one bucket has two fields holding the bucket algorithm. If the values
in these two fields differ, an out-of-bounds access can occur. This is
the case because the first algorithm field (alg) is used to allocate
the correct amount of memory for a bucket of this type, while the second
algorithm field inside the bucket (b->alg) is used in the subsequent
processing.
This patch fixes the issue by adding a check that compares alg and
b->alg and aborts the processing in case they differ. Furthermore,
b->alg is set to 0 in this case, because the destruction of the crush
map also uses this field to determine the bucket type, which can again
result in an out-of-bounds access when trying to free the memory pointed
to by the fields of the bucket. To correctly free the memory allocated
for the bucket in such a case, the corresponding call to kfree is moved
from the algorithm-specific crush_destroy_bucket functions to the
generic crush_destroy_bucket(). |
| In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Fix oops due to out of scope access
Below oops triggers when kill QEMU process:
Oops: general protection fault, probably for non-canonical address 0x7fffffff844eaaa7: 0000 [#1] SMP NOPTI
Call Trace:
<TASK>
do_raw_spin_lock+0xaa/0xc0
_raw_spin_lock_irqsave+0x21/0x40
domain_remove_dev_pasid+0x52/0x160
intel_nested_set_dev_pasid+0x1b9/0x1e0
__iommu_set_group_pasid+0x56/0x120
pci_dev_reset_iommu_done+0xe3/0x180
pcie_flr+0x65/0x160
__pci_reset_function_locked+0x5b/0x120
vfio_pci_core_close_device+0x63/0xe0 [vfio_pci_core]
vfio_df_close+0x4f/0xa0
vfio_df_unbind_iommufd+0x2d/0x60
vfio_device_fops_release+0x3e/0x40
__fput+0xe5/0x2c0
task_work_run+0x58/0xa0
do_exit+0x2c8/0x600
do_group_exit+0x2f/0xa0
get_signal+0x863/0x8c0
arch_do_signal_or_restart+0x24/0x100
exit_to_user_mode_loop+0x87/0x380
do_syscall_64+0x2ff/0x11e0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
The global static blocked domain is a dummy domain without corresponding
dmar_domain structure, accessing beyond iommu_domain structure triggers
oops easily. Fix it by return early in domain_remove_dev_pasid() like
identity domain. |
| In the Linux kernel, the following vulnerability has been resolved:
iommu: Fix WARN_ON in __iommu_group_set_domain_nofail() due to reset
In __iommu_group_set_domain_internal(), concurrent domain attachments are
rejected when any device in the group is recovering. This is necessary to
fence concurrent attachments to a multi-device group where devices might
share the same RID due to PCI DMA alias quirks, but triggers the WARN_ON in
__iommu_group_set_domain_nofail().
Other IOMMU_SET_DOMAIN_MUST_SUCCEED callers in detach/teardown paths, such
as __iommu_group_set_core_domain and __iommu_release_dma_ownership, should
not be rejected, as the domain would be freed anyway in these nofail paths
while group->domain is still pointing to it. So pci_dev_reset_iommu_done()
could trigger a UAF when re-attaching group->domain.
Honor the IOMMU_SET_DOMAIN_MUST_SUCCEED flag, allowing the callers through
the group->recovery_cnt fence, so as to update the group->domain pointer.
Instead add a gdev->blocked check in the device iteration loop, to prevent
any concurrent per-device detachment. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/xe/dma-buf: handle empty bo and UAF races
There look to be some nasty races here when triggering the
invalidate_mappings hook:
1) We do xe_bo_alloc() followed by the attach, before the actual full bo
init step in xe_dma_buf_init_obj(). However the bo is visible on the
attachments list after the attach. This is bad since exporter driver,
say amdgpu, can at any time call back into our invalidate_mappings hook,
with an empty/bogus bo, leading to potential bugs/crashes.
2) Similar to 1) but here we get a UAF, when the invalidate_mappings
hook is triggered. For example, we get as far as xe_bo_init_locked()
but this fails in some way. But here the bo will be freed on error, but
we still have it attached from dma-buf pov, so if the
invalidate_mappings is now triggered then the bo we access is gone and
we trigger UAF and more bugs/crashes.
To fix this, move the attach step until after we actually have a fully
set up buffer object. Note that the bo is not published to userspace
until later, so not sure what the comment "Don't publish the bo
until we have a valid attachment", is referring to.
We have at least two different customers reporting hitting a NULL ptr
deref in evict_flags when importing something from amdgpu, followed by
triggering the evict flow. Hit rate is also pretty low, which would
hint at some kind of race, so something like 1) or 2) might explain
this.
v2:
- Shuffle the order of the ops slightly (no functional change)
- Improve the comment to better explain the ordering (Matt B)
(cherry picked from commit af1f2ad0c59fe4e2f924c526f66e968289d77971) |
| In the Linux kernel, the following vulnerability has been resolved:
drm/xe/dma-buf: fix UAF with retry loop
Retry doesn't work here, since bo will be freed on error, leading to
UAF. However, now that we do the alloc & init before the attach, we can
now combine this as one unit and have the init do the alloc for us. This
should make the retry safe.
Reported by Sashiko.
v2: Fix up the error unwind (CI)
(cherry picked from commit 479669418253e0f27f8cf5db01a731352ea592e7) |
| In the Linux kernel, the following vulnerability has been resolved:
net: qrtr: fix refcount saturation and potential UAF in qrtr_port_remove
In qrtr_port_remove(), the socket reference count is decremented via
__sock_put() before the port is removed from the qrtr_ports XArray and
before the RCU grace period elapses.
This breaks the fundamental RCU update paradigm. It exposes a race
window where a concurrent RCU reader (such as qrtr_reset_ports() or
qrtr_port_lookup()) can obtain a pointer to the socket from the XArray,
and attempt to call sock_hold() on a socket whose reference count has
already dropped to zero.
This exact race condition was hit during syzkaller fuzzing, leading to
the following refcount saturation warning and a potential Use-After-Free:
refcount_t: saturated; leaking memory.
WARNING: CPU: 3 PID: 1273 at lib/refcount.c:22 refcount_warn_saturate+0xae/0x1d0
Modules linked in: qrtr(+) bochs drm_shmem_helper ...
Call Trace:
<TASK>
qrtr_reset_ports net/qrtr/af_qrtr.c:768 [inline] [qrtr]
__qrtr_bind.isra.0+0x48b/0x570 net/qrtr/af_qrtr.c:805 [qrtr]
qrtr_bind+0x17d/0x210 net/qrtr/af_qrtr.c:901 [qrtr]
kernel_bind+0xe4/0x120 net/socket.c:3592
qrtr_ns_init+0x1a6/0x380 net/qrtr/ns.c:715 [qrtr]
qrtr_proto_init+0x3b/0xff0 net/qrtr/af_qrtr.c:169 [qrtr]
do_one_initcall+0xf5/0x5e0 init/main.c:1283
...
</TASK>
Fix this by deferring the reference count decrement until after the
xa_erase() and the synchronize_rcu() complete.
(Note: The v1 of this patch incorrectly replaced __sock_put() with
sock_put(). As Simon Horman pointed out, the callers of qrtr_port_remove()
still hold a reference to the socket, so freeing the socket memory here
would lead to a subsequent UAF in the caller. Thus, the __sock_put() is
kept, but only repositioned to close the RCU race.) |
| 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--- |