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🚨 CVE-2024-26990
In the Linux kernel, the following vulnerability has been resolved:

KVM: x86/mmu: Write-protect L2 SPTEs in TDP MMU when clearing dirty status

Check kvm_mmu_page_ad_need_write_protect() when deciding whether to
write-protect or clear D-bits on TDP MMU SPTEs, so that the TDP MMU
accounts for any role-specific reasons for disabling D-bit dirty logging.

Specifically, TDP MMU SPTEs must be write-protected when the TDP MMU is
being used to run an L2 (i.e. L1 has disabled EPT) and PML is enabled.
KVM always disables PML when running L2, even when L1 and L2 GPAs are in
the some domain, so failing to write-protect TDP MMU SPTEs will cause
writes made by L2 to not be reflected in the dirty log.

[sean: massage shortlog and changelog, tweak ternary op formatting]

🎖@cveNotify
🚨 CVE-2024-26992
In the Linux kernel, the following vulnerability has been resolved:

KVM: x86/pmu: Disable support for adaptive PEBS

Drop support for virtualizing adaptive PEBS, as KVM's implementation is
architecturally broken without an obvious/easy path forward, and because
exposing adaptive PEBS can leak host LBRs to the guest, i.e. can leak
host kernel addresses to the guest.

Bug #1 is that KVM doesn't account for the upper 32 bits of
IA32_FIXED_CTR_CTRL when (re)programming fixed counters, e.g
fixed_ctrl_field() drops the upper bits, reprogram_fixed_counters()
stores local variables as u8s and truncates the upper bits too, etc.

Bug #2 is that, because KVM _always_ sets precise_ip to a non-zero value
for PEBS events, perf will _always_ generate an adaptive record, even if
the guest requested a basic record. Note, KVM will also enable adaptive
PEBS in individual *counter*, even if adaptive PEBS isn't exposed to the
guest, but this is benign as MSR_PEBS_DATA_CFG is guaranteed to be zero,
i.e. the guest will only ever see Basic records.

Bug #3 is in perf. intel_pmu_disable_fixed() doesn't clear the upper
bits either, i.e. leaves ICL_FIXED_0_ADAPTIVE set, and
intel_pmu_enable_fixed() effectively doesn't clear ICL_FIXED_0_ADAPTIVE
either. I.e. perf _always_ enables ADAPTIVE counters, regardless of what
KVM requests.

Bug #4 is that adaptive PEBS *might* effectively bypass event filters set
by the host, as "Updated Memory Access Info Group" records information
that might be disallowed by userspace via KVM_SET_PMU_EVENT_FILTER.

Bug #5 is that KVM doesn't ensure LBR MSRs hold guest values (or at least
zeros) when entering a vCPU with adaptive PEBS, which allows the guest
to read host LBRs, i.e. host RIPs/addresses, by enabling "LBR Entries"
records.

Disable adaptive PEBS support as an immediate fix due to the severity of
the LBR leak in particular, and because fixing all of the bugs will be
non-trivial, e.g. not suitable for backporting to stable kernels.

Note! This will break live migration, but trying to make KVM play nice
with live migration would be quite complicated, wouldn't be guaranteed to
work (i.e. KVM might still kill/confuse the guest), and it's not clear
that there are any publicly available VMMs that support adaptive PEBS,
let alone live migrate VMs that support adaptive PEBS, e.g. QEMU doesn't
support PEBS in any capacity.

🎖@cveNotify
🚨 CVE-2024-26994
In the Linux kernel, the following vulnerability has been resolved:

speakup: Avoid crash on very long word

In case a console is set up really large and contains a really long word
(> 256 characters), we have to stop before the length of the word buffer.

🎖@cveNotify
🚨 CVE-2024-26996
In the Linux kernel, the following vulnerability has been resolved:

usb: gadget: f_ncm: Fix UAF ncm object at re-bind after usb ep transport error

When ncm function is working and then stop usb0 interface for link down,
eth_stop() is called. At this piont, accidentally if usb transport error
should happen in usb_ep_enable(), 'in_ep' and/or 'out_ep' may not be enabled.

After that, ncm_disable() is called to disable for ncm unbind
but gether_disconnect() is never called since 'in_ep' is not enabled.

As the result, ncm object is released in ncm unbind
but 'dev->port_usb' associated to 'ncm->port' is not NULL.

And when ncm bind again to recover netdev, ncm object is reallocated
but usb0 interface is already associated to previous released ncm object.

Therefore, once usb0 interface is up and eth_start_xmit() is called,
released ncm object is dereferrenced and it might cause use-after-free memory.

[function unlink via configfs]
usb0: eth_stop dev->port_usb=ffffff9b179c3200
--> error happens in usb_ep_enable().
NCM: ncm_disable: ncm=ffffff9b179c3200
--> no gether_disconnect() since ncm->port.in_ep->enabled is false.
NCM: ncm_unbind: ncm unbind ncm=ffffff9b179c3200
NCM: ncm_free: ncm free ncm=ffffff9b179c3200 <-- released ncm

[function link via configfs]
NCM: ncm_alloc: ncm alloc ncm=ffffff9ac4f8a000
NCM: ncm_bind: ncm bind ncm=ffffff9ac4f8a000
NCM: ncm_set_alt: ncm=ffffff9ac4f8a000 alt=0
usb0: eth_open dev->port_usb=ffffff9b179c3200 <-- previous released ncm
usb0: eth_start dev->port_usb=ffffff9b179c3200 <--
eth_start_xmit()
--> dev->wrap()
Unable to handle kernel paging request at virtual address dead00000000014f

This patch addresses the issue by checking if 'ncm->netdev' is not NULL at
ncm_disable() to call gether_disconnect() to deassociate 'dev->port_usb'.
It's more reasonable to check 'ncm->netdev' to call gether_connect/disconnect
rather than check 'ncm->port.in_ep->enabled' since it might not be enabled
but the gether connection might be established.

🎖@cveNotify
🚨 CVE-2024-27005
In the Linux kernel, the following vulnerability has been resolved:

interconnect: Don't access req_list while it's being manipulated

The icc_lock mutex was split into separate icc_lock and icc_bw_lock
mutexes in [1] to avoid lockdep splats. However, this didn't adequately
protect access to icc_node::req_list.

The icc_set_bw() function will eventually iterate over req_list while
only holding icc_bw_lock, but req_list can be modified while only
holding icc_lock. This causes races between icc_set_bw(), of_icc_get(),
and icc_put().

Example A:

CPU0 CPU1
---- ----
icc_set_bw(path_a)
mutex_lock(&icc_bw_lock);
icc_put(path_b)
mutex_lock(&icc_lock);
aggregate_requests()
hlist_for_each_entry(r, ...
hlist_del(...
<r = invalid pointer>

Example B:

CPU0 CPU1
---- ----
icc_set_bw(path_a)
mutex_lock(&icc_bw_lock);
path_b = of_icc_get()
of_icc_get_by_index()
mutex_lock(&icc_lock);
path_find()
path_init()
aggregate_requests()
hlist_for_each_entry(r, ...
hlist_add_head(...
<r = invalid pointer>

Fix this by ensuring icc_bw_lock is always held before manipulating
icc_node::req_list. The additional places icc_bw_lock is held don't
perform any memory allocations, so we should still be safe from the
original lockdep splats that motivated the separate locks.

[1] commit af42269c3523 ("interconnect: Fix locking for runpm vs reclaim")

🎖@cveNotify
🚨 CVE-2024-27007
In the Linux kernel, the following vulnerability has been resolved:

userfaultfd: change src_folio after ensuring it's unpinned in UFFDIO_MOVE

Commit d7a08838ab74 ("mm: userfaultfd: fix unexpected change to src_folio
when UFFDIO_MOVE fails") moved the src_folio->{mapping, index} changing to
after clearing the page-table and ensuring that it's not pinned. This
avoids failure of swapout+migration and possibly memory corruption.

However, the commit missed fixing it in the huge-page case.

🎖@cveNotify
🚨 CVE-2024-27012
In the Linux kernel, the following vulnerability has been resolved:

netfilter: nf_tables: restore set elements when delete set fails

From abort path, nft_mapelem_activate() needs to restore refcounters to
the original state. Currently, it uses the set->ops->walk() to iterate
over these set elements. The existing set iterator skips inactive
elements in the next generation, this does not work from the abort path
to restore the original state since it has to skip active elements
instead (not inactive ones).

This patch moves the check for inactive elements to the set iterator
callback, then it reverses the logic for the .activate case which
needs to skip active elements.

Toggle next generation bit for elements when delete set command is
invoked and call nft_clear() from .activate (abort) path to restore the
next generation bit.

The splat below shows an object in mappings memleak:

[43929.457523] ------------[ cut here ]------------
[43929.457532] WARNING: CPU: 0 PID: 1139 at include/net/netfilter/nf_tables.h:1237 nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables]
[...]
[43929.458014] RIP: 0010:nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables]
[43929.458076] Code: 83 f8 01 77 ab 49 8d 7c 24 08 e8 37 5e d0 de 49 8b 6c 24 08 48 8d 7d 50 e8 e9 5c d0 de 8b 45 50 8d 50 ff 89 55 50 85 c0 75 86 <0f> 0b eb 82 0f 0b eb b3 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90
[43929.458081] RSP: 0018:ffff888140f9f4b0 EFLAGS: 00010246
[43929.458086] RAX: 0000000000000000 RBX: ffff8881434f5288 RCX: dffffc0000000000
[43929.458090] RDX: 00000000ffffffff RSI: ffffffffa26d28a7 RDI: ffff88810ecc9550
[43929.458093] RBP: ffff88810ecc9500 R08: 0000000000000001 R09: ffffed10281f3e8f
[43929.458096] R10: 0000000000000003 R11: ffff0000ffff0000 R12: ffff8881434f52a0
[43929.458100] R13: ffff888140f9f5f4 R14: ffff888151c7a800 R15: 0000000000000002
[43929.458103] FS: 00007f0c687c4740(0000) GS:ffff888390800000(0000) knlGS:0000000000000000
[43929.458107] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[43929.458111] CR2: 00007f58dbe5b008 CR3: 0000000123602005 CR4: 00000000001706f0
[43929.458114] Call Trace:
[43929.458118] <TASK>
[43929.458121] ? __warn+0x9f/0x1a0
[43929.458127] ? nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables]
[43929.458188] ? report_bug+0x1b1/0x1e0
[43929.458196] ? handle_bug+0x3c/0x70
[43929.458200] ? exc_invalid_op+0x17/0x40
[43929.458211] ? nft_setelem_data_deactivate+0xd7/0xf0 [nf_tables]
[43929.458271] ? nft_setelem_data_deactivate+0xe4/0xf0 [nf_tables]
[43929.458332] nft_mapelem_deactivate+0x24/0x30 [nf_tables]
[43929.458392] nft_rhash_walk+0xdd/0x180 [nf_tables]
[43929.458453] ? __pfx_nft_rhash_walk+0x10/0x10 [nf_tables]
[43929.458512] ? rb_insert_color+0x2e/0x280
[43929.458520] nft_map_deactivate+0xdc/0x1e0 [nf_tables]
[43929.458582] ? __pfx_nft_map_deactivate+0x10/0x10 [nf_tables]
[43929.458642] ? __pfx_nft_mapelem_deactivate+0x10/0x10 [nf_tables]
[43929.458701] ? __rcu_read_unlock+0x46/0x70
[43929.458709] nft_delset+0xff/0x110 [nf_tables]
[43929.458769] nft_flush_table+0x16f/0x460 [nf_tables]
[43929.458830] nf_tables_deltable+0x501/0x580 [nf_tables]

🎖@cveNotify
🚨 CVE-2024-27016
In the Linux kernel, the following vulnerability has been resolved:

netfilter: flowtable: validate pppoe header

Ensure there is sufficient room to access the protocol field of the
PPPoe header. Validate it once before the flowtable lookup, then use a
helper function to access protocol field.

🎖@cveNotify
🚨 CVE-2024-27017
In the Linux kernel, the following vulnerability has been resolved:

netfilter: nft_set_pipapo: walk over current view on netlink dump

The generation mask can be updated while netlink dump is in progress.
The pipapo set backend walk iterator cannot rely on it to infer what
view of the datastructure is to be used. Add notation to specify if user
wants to read/update the set.

Based on patch from Florian Westphal.

🎖@cveNotify
🚨 CVE-2024-27018
In the Linux kernel, the following vulnerability has been resolved:

netfilter: br_netfilter: skip conntrack input hook for promisc packets

For historical reasons, when bridge device is in promisc mode, packets
that are directed to the taps follow bridge input hook path. This patch
adds a workaround to reset conntrack for these packets.

Jianbo Liu reports warning splats in their test infrastructure where
cloned packets reach the br_netfilter input hook to confirm the
conntrack object.

Scratch one bit from BR_INPUT_SKB_CB to annotate that this packet has
reached the input hook because it is passed up to the bridge device to
reach the taps.

[ 57.571874] WARNING: CPU: 1 PID: 0 at net/bridge/br_netfilter_hooks.c:616 br_nf_local_in+0x157/0x180 [br_netfilter]
[ 57.572749] Modules linked in: xt_MASQUERADE nf_conntrack_netlink nfnetlink iptable_nat xt_addrtype xt_conntrack nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcgss oid_registry overlay rpcrdma rdma_ucm ib_iser libiscsi scsi_transport_isc si ib_umad rdma_cm ib_ipoib iw_cm ib_cm mlx5_ib ib_uverbs ib_core mlx5ctl mlx5_core
[ 57.575158] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.8.0+ #19
[ 57.575700] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[ 57.576662] RIP: 0010:br_nf_local_in+0x157/0x180 [br_netfilter]
[ 57.577195] Code: fe ff ff 41 bd 04 00 00 00 be 04 00 00 00 e9 4a ff ff ff be 04 00 00 00 48 89 ef e8 f3 a9 3c e1 66 83 ad b4 00 00 00 04 eb 91 <0f> 0b e9 f1 fe ff ff 0f 0b e9 df fe ff ff 48 89 df e8 b3 53 47 e1
[ 57.578722] RSP: 0018:ffff88885f845a08 EFLAGS: 00010202
[ 57.579207] RAX: 0000000000000002 RBX: ffff88812dfe8000 RCX: 0000000000000000
[ 57.579830] RDX: ffff88885f845a60 RSI: ffff8881022dc300 RDI: 0000000000000000
[ 57.580454] RBP: ffff88885f845a60 R08: 0000000000000001 R09: 0000000000000003
[ 57.581076] R10: 00000000ffff1300 R11: 0000000000000002 R12: 0000000000000000
[ 57.581695] R13: ffff8881047ffe00 R14: ffff888108dbee00 R15: ffff88814519b800
[ 57.582313] FS: 0000000000000000(0000) GS:ffff88885f840000(0000) knlGS:0000000000000000
[ 57.583040] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 57.583564] CR2: 000000c4206aa000 CR3: 0000000103847001 CR4: 0000000000370eb0
[ 57.584194] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[ 57.584820] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[ 57.585440] Call Trace:
[ 57.585721] <IRQ>
[ 57.585976] ? __warn+0x7d/0x130
[ 57.586323] ? br_nf_local_in+0x157/0x180 [br_netfilter]
[ 57.586811] ? report_bug+0xf1/0x1c0
[ 57.587177] ? handle_bug+0x3f/0x70
[ 57.587539] ? exc_invalid_op+0x13/0x60
[ 57.587929] ? asm_exc_invalid_op+0x16/0x20
[ 57.588336] ? br_nf_local_in+0x157/0x180 [br_netfilter]
[ 57.588825] nf_hook_slow+0x3d/0xd0
[ 57.589188] ? br_handle_vlan+0x4b/0x110
[ 57.589579] br_pass_frame_up+0xfc/0x150
[ 57.589970] ? br_port_flags_change+0x40/0x40
[ 57.590396] br_handle_frame_finish+0x346/0x5e0
[ 57.590837] ? ipt_do_table+0x32e/0x430
[ 57.591221] ? br_handle_local_finish+0x20/0x20
[ 57.591656] br_nf_hook_thresh+0x4b/0xf0 [br_netfilter]
[ 57.592286] ? br_handle_local_finish+0x20/0x20
[ 57.592802] br_nf_pre_routing_finish+0x178/0x480 [br_netfilter]
[ 57.593348] ? br_handle_local_finish+0x20/0x20
[ 57.593782] ? nf_nat_ipv4_pre_routing+0x25/0x60 [nf_nat]
[ 57.594279] br_nf_pre_routing+0x24c/0x550 [br_netfilter]
[ 57.594780] ? br_nf_hook_thresh+0xf0/0xf0 [br_netfilter]
[ 57.595280] br_handle_frame+0x1f3/0x3d0
[ 57.595676] ? br_handle_local_finish+0x20/0x20
[ 57.596118] ? br_handle_frame_finish+0x5e0/0x5e0
[ 57.596566] __netif_receive_skb_core+0x25b/0xfc0
[ 57.597017] ? __napi_build_skb+0x37/0x40
[ 57.597418] __netif_receive_skb_list_core+0xfb/0x220

🎖@cveNotify
🚨 CVE-2024-27019
In the Linux kernel, the following vulnerability has been resolved:

netfilter: nf_tables: Fix potential data-race in __nft_obj_type_get()

nft_unregister_obj() can concurrent with __nft_obj_type_get(),
and there is not any protection when iterate over nf_tables_objects
list in __nft_obj_type_get(). Therefore, there is potential data-race
of nf_tables_objects list entry.

Use list_for_each_entry_rcu() to iterate over nf_tables_objects
list in __nft_obj_type_get(), and use rcu_read_lock() in the caller
nft_obj_type_get() to protect the entire type query process.

🎖@cveNotify
🚨 CVE-2024-27020
In the Linux kernel, the following vulnerability has been resolved:

netfilter: nf_tables: Fix potential data-race in __nft_expr_type_get()

nft_unregister_expr() can concurrent with __nft_expr_type_get(),
and there is not any protection when iterate over nf_tables_expressions
list in __nft_expr_type_get(). Therefore, there is potential data-race
of nf_tables_expressions list entry.

Use list_for_each_entry_rcu() to iterate over nf_tables_expressions
list in __nft_expr_type_get(), and use rcu_read_lock() in the caller
nft_expr_type_get() to protect the entire type query process.

🎖@cveNotify
🚨 CVE-2024-27022
In the Linux kernel, the following vulnerability has been resolved:

fork: defer linking file vma until vma is fully initialized

Thorvald reported a WARNING [1]. And the root cause is below race:

CPU 1 CPU 2
fork hugetlbfs_fallocate
dup_mmap hugetlbfs_punch_hole
i_mmap_lock_write(mapping);
vma_interval_tree_insert_after -- Child vma is visible through i_mmap tree.
i_mmap_unlock_write(mapping);
hugetlb_dup_vma_private -- Clear vma_lock outside i_mmap_rwsem!
i_mmap_lock_write(mapping);
hugetlb_vmdelete_list
vma_interval_tree_foreach
hugetlb_vma_trylock_write -- Vma_lock is cleared.
tmp->vm_ops->open -- Alloc new vma_lock outside i_mmap_rwsem!
hugetlb_vma_unlock_write -- Vma_lock is assigned!!!
i_mmap_unlock_write(mapping);

hugetlb_dup_vma_private() and hugetlb_vm_op_open() are called outside
i_mmap_rwsem lock while vma lock can be used in the same time. Fix this
by deferring linking file vma until vma is fully initialized. Those vmas
should be initialized first before they can be used.

🎖@cveNotify
🚨 CVE-2024-27026
In the Linux kernel, the following vulnerability has been resolved:

vmxnet3: Fix missing reserved tailroom

Use rbi->len instead of rcd->len for non-dataring packet.

Found issue:
XDP_WARN: xdp_update_frame_from_buff(line:278): Driver BUG: missing reserved tailroom
WARNING: CPU: 0 PID: 0 at net/core/xdp.c:586 xdp_warn+0xf/0x20
CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W O 6.5.1 #1
RIP: 0010:xdp_warn+0xf/0x20
...
? xdp_warn+0xf/0x20
xdp_do_redirect+0x15f/0x1c0
vmxnet3_run_xdp+0x17a/0x400 [vmxnet3]
vmxnet3_process_xdp+0xe4/0x760 [vmxnet3]
? vmxnet3_tq_tx_complete.isra.0+0x21e/0x2c0 [vmxnet3]
vmxnet3_rq_rx_complete+0x7ad/0x1120 [vmxnet3]
vmxnet3_poll_rx_only+0x2d/0xa0 [vmxnet3]
__napi_poll+0x20/0x180
net_rx_action+0x177/0x390

🎖@cveNotify
🚨 CVE-2024-27029
In the Linux kernel, the following vulnerability has been resolved:

drm/amdgpu: fix mmhub client id out-of-bounds access

Properly handle cid 0x140.

🎖@cveNotify
🚨 CVE-2024-27034
In the Linux kernel, the following vulnerability has been resolved:

f2fs: compress: fix to cover normal cluster write with cp_rwsem

When we overwrite compressed cluster w/ normal cluster, we should
not unlock cp_rwsem during f2fs_write_raw_pages(), otherwise data
will be corrupted if partial blocks were persisted before CP & SPOR,
due to cluster metadata wasn't updated atomically.

🎖@cveNotify
🚨 CVE-2024-27035
In the Linux kernel, the following vulnerability has been resolved:

f2fs: compress: fix to guarantee persisting compressed blocks by CP

If data block in compressed cluster is not persisted with metadata
during checkpoint, after SPOR, the data may be corrupted, let's
guarantee to write compressed page by checkpoint.

🎖@cveNotify
🚨 CVE-2024-27043
In the Linux kernel, the following vulnerability has been resolved:

media: edia: dvbdev: fix a use-after-free

In dvb_register_device, *pdvbdev is set equal to dvbdev, which is freed
in several error-handling paths. However, *pdvbdev is not set to NULL
after dvbdev's deallocation, causing use-after-frees in many places,
for example, in the following call chain:

budget_register
|-> dvb_dmxdev_init
|-> dvb_register_device
|-> dvb_dmxdev_release
|-> dvb_unregister_device
|-> dvb_remove_device
|-> dvb_device_put
|-> kref_put

When calling dvb_unregister_device, dmxdev->dvbdev (i.e. *pdvbdev in
dvb_register_device) could point to memory that had been freed in
dvb_register_device. Thereafter, this pointer is transferred to
kref_put and triggering a use-after-free.

🎖@cveNotify
🚨 CVE-2024-27045
In the Linux kernel, the following vulnerability has been resolved:

drm/amd/display: Fix a potential buffer overflow in 'dp_dsc_clock_en_read()'

Tell snprintf() to store at most 10 bytes in the output buffer
instead of 30.

Fixes the below:
drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_debugfs.c:1508 dp_dsc_clock_en_read() error: snprintf() is printing too much 30 vs 10

🎖@cveNotify
🚨 CVE-2024-27050
In the Linux kernel, the following vulnerability has been resolved:

libbpf: Use OPTS_SET() macro in bpf_xdp_query()

When the feature_flags and xdp_zc_max_segs fields were added to the libbpf
bpf_xdp_query_opts, the code writing them did not use the OPTS_SET() macro.
This causes libbpf to write to those fields unconditionally, which means
that programs compiled against an older version of libbpf (with a smaller
size of the bpf_xdp_query_opts struct) will have its stack corrupted by
libbpf writing out of bounds.

The patch adding the feature_flags field has an early bail out if the
feature_flags field is not part of the opts struct (via the OPTS_HAS)
macro, but the patch adding xdp_zc_max_segs does not. For consistency, this
fix just changes the assignments to both fields to use the OPTS_SET()
macro.

🎖@cveNotify
🚨 CVE-2024-27052
In the Linux kernel, the following vulnerability has been resolved:

wifi: rtl8xxxu: add cancel_work_sync() for c2hcmd_work

The workqueue might still be running, when the driver is stopped. To
avoid a use-after-free, call cancel_work_sync() in rtl8xxxu_stop().

🎖@cveNotify