| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: scsi_debug: Fix REPORT ZONES alloc_len underflow OOB write
resp_report_zones() sizes the reply buffer from the CDB allocation
length. The v3 fix rounds alloc_len up with ALIGN() before deriving the
descriptor count:
rep_max_zones = (ALIGN((u64)alloc_len, RZONES_DESC_HD) -
RZONES_DESC_HD) >> ilog2(RZONES_DESC_HD);
arr_len = (u64)RZONES_DESC_HD * (rep_max_zones + 1);
For alloc_len in 0xFFFFFFC1..0xFFFFFFFF, ALIGN() rounds up to
0x100000000, so arr_len is 4 GB. On 32-bit, kzalloc()'s size_t is 32-bit
and truncates 0x100000000 to 0; kzalloc(0) returns ZERO_SIZE_PTR, which
passes the !arr check, and desc = arr + 64 is then dereferenced in the
loop -> out-of-bounds write / panic.
Clamp rep_max_zones to devip->nr_zones. The loop already stops at
sdebug_capacity (after nr_zones zones), so a report can never hold more
than nr_zones descriptors; the clamp does not change the report, it only
bounds arr_len to (nr_zones + 1) * RZONES_DESC_HD, a real device
property that can never reach 0x100000000. |
| In the Linux kernel, the following vulnerability has been resolved:
can: peak_usb: peak_usb_start(): fix double free of transfer buffer on URB submit error
In peak_usb_start(), each RX URB transfer buffer is allocated with kmalloc()
and the URB is flagged URB_FREE_BUFFER so that the final usb_free_urb() also
frees the transfer buffer.
If usb_submit_urb() fails, the error path frees the buffer explicitly with
kfree(buf) and then calls usb_free_urb(urb). Because URB_FREE_BUFFER is set,
usb_free_urb() -> urb_destroy() frees the same buffer a second time, a double
free of the transfer buffer.
BUG: KASAN: double-free in usb_free_urb.part.0+0x91/0xb0
Free of addr ffff8881069ccb80 by task trigger.sh/285
Call Trace:
kfree+0x113/0x3c0
usb_free_urb.part.0+0x91/0xb0
Drop the redundant kfree(buf); usb_free_urb() already releases the transfer
buffer. This mirrors commit 03819abbeb11 ("net: usb: lan78xx: Fix double free
issue with interrupt buffer allocation"). |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: fix uint32_t overflow in EOP ring buffer size alignment
eop_ring_buffer_size in struct queue_properties is a u32. In
kfd_queue_acquire_buffers() the expected EOP buffer size is computed as
ALIGN(eop_ring_buffer_size, PAGE_SIZE); ALIGN uses typeof(x), so the
addition is done in 32-bit. A user-supplied size of 0xFFFFF001 wraps to
0, causing kfd_queue_buffer_get() to skip its exact-size check (gated on
size != 0) and accept any BO mapped at the address. On GFX8/GFX9 the MQD
cp_hqd_eop_control is then programmed for an 8KB EOP ring backed by a 4KB
BO, so CP EOP writes can land past the buffer and fault the GPU.
Cast the operand to u64 so the alignment is computed in 64-bit; the size
check in kfd_queue_buffer_get() then rejects the oversized request.
(cherry picked from commit ae443117b742c357bfef3a7bddabf76fcf86e9ef) |
| In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Clear Present bit before tearing down scalable-mode context entry
device_pasid_table_teardown() zeroes the 128-bit scalable-mode context
entry with context_clear_entry() while the Present bit is still set. This
creates a window where the hardware can fetch a torn entry, with some
fields already zeroed while Present is still set, leading to unpredictable
behavior or spurious faults. The context-cache invalidation is issued only
after the entry has been zeroed, and intel_pasid_free_table() then frees
the PASID directory pages, so the IOMMU can keep walking a stale Present=1
entry that points at freed memory.
While x86 provides strong write ordering, the compiler may reorder the two
64-bit writes to the entry, and the hardware fetch is not guaranteed to be
atomic with respect to multiple CPU writes.
Commit c1e4f1dccbe9d ("iommu/vt-d: Clear Present bit before tearing down
context entry") fixed this exact pattern in domain_context_clear_one() and
the copied-context path, but device_pasid_table_teardown() was not
converted.
Align it with the "Guidance to Software for Invalidations" in the VT-d
spec, Section 6.5.3.3, using the same ownership handshake as the sibling
fix: clear only the Present bit, flush it to the IOMMU, perform the
context-cache invalidation, and only then zero the rest of the entry. |
| In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Fix ACKALL packet handling
rxrpc_input_ackall() accepts ACKALL packets without checking whether the
call is in a state that can legitimately have outstanding transmit buffers.
A forged ACKALL can therefore reach a new service call in
RXRPC_CALL_SERVER_RECV_REQUEST before any reply packets have been queued.
In that state call->tx_top is zero and call->tx_queue is NULL, so
rxrpc_rotate_tx_window() dereferences a NULL txqueue and triggers a
null-pointer dereference.
Fix the handling of ACKALL packets by the following means:
(1) Add two new call states: RXRPC_CALL_CLIENT_PRE_SEND which indicates
that the client call is connected, but nothing has been transmitted as
yet; and RXRPC_CALL_CLIENT_AWAIT_ACK, which indicates that everything
has been transmitted at least once, but we're now waiting for the
stuff remaining in the Tx buffer to be ACK'd (retransmissions may
still happen).
The RXRPC_CALL_CLIENT_PRE_SEND state is set when the call is assigned
a channel and transitions to RXRPC_CALL_CLIENT_SEND_REQUEST when the
first packet is transmitted.
RXRPC_CALL_CLIENT_AWAIT_REPLY is then narrowed in scope to indicate
that all Tx packets have been ACK'd and we're now waiting for the
reply to be received.
(2) As per Wyatt Feng's original patch[1], the ACKALL handler then checks
that the call state is one in which there might be stuff in the Tx
buffer to ACK, but now this includes AWAIT_ACK rather than
AWAIT_REPLY. ACKALL packets are ignored if received in the wrong
state.
Note that unlike Wyatt Feng's patch, it's no longer necessary to check
to see if the Tx buffer exists as this the state set now covers this.
(3) Make the ACKALL handler use call->tx_transmitted rather than
call->tx_top as the former is explicitly the highest packet seq number
transmitted, whereas the latter has a looser definition.
Thanks to Jeffrey Altman for a description of the history of the ACKALL
packet[1]. |
| In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Fix the reception of a reply packet before data transmission
Fix rxrpc_receiving_reply() to handle the reception of an apparent reply
DATA packet before rxrpc has had a chance to send any request DATA packets
on a client call by checking to see if the call has been exposed yet by
sending the first packet.
Without this, rxrpc_rotate_tx_window() might oops.
Also fix rxrpc_rotate_tx_window() to handle the Tx queue being empty by
changing the do...while loop into a while loop, just in case a call is
abnormally terminated by an early reply before the last request packet is
transmitted. |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: ccp - Fix snp_filter_reserved_mem_regions() off-by-one
Sashiko notes:
> regarding the bounds check in snp_filter_reserved_mem_regions()
> called via walk_iomem_res_desc(): does the check
> if ((range_list->num_elements * 16 + 8) > PAGE_SIZE)
> allow an off-by-one heap buffer overflow?
>
> If range_list->num_elements is 255, 255 * 16 + 8 = 4088, which is <= 4096.
> Writing range->base (8 bytes) fills 4088-4095, but writing range->page_count
> (4 bytes) would write to 4096-4099, overflowing the kzalloc-allocated
> PAGE_SIZE buffer.
Fix this by accounting for the entry about to be written to, in addition to
the entries that are already allocated. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/mlx5: Fix UMR XLT cleanup on ODP populate failure
mlx5r_umr_update_xlt() allocates and DMA maps an XLT buffer with
mlx5r_umr_create_xlt(). The buffer is released by the common cleanup path
through mlx5r_umr_unmap_free_xlt().
After mlx5_odp_populate_xlt() became fallible, its error path returned
directly and skipped that cleanup. This leaks the XLT DMA mapping and
buffer. If the emergency XLT page was used, it also leaves
xlt_emergency_page_mutex locked.
Break out of the loop so execution falls through the existing cleanup path. |
| In the Linux kernel, the following vulnerability has been resolved:
nvme-multipath: fix flex array size in struct nvme_ns_head
struct nvme_ns_head contains a flexible array member, current_path[],
which is indexed using the NUMA node ID:
head->current_path[numa_node_id()]
The structure is currently allocated as:
size = sizeof(struct nvme_ns_head) +
(num_possible_nodes() * sizeof(struct nvme_ns *));
head = kzalloc(size, GFP_KERNEL);
This allocation assumes that NUMA node IDs are sequential and densely
packed from 0 .. num_possible_nodes() - 1. While this assumption holds
on many systems, it is not always true on some architectures such as
powerpc.
On some powerpc systems, NUMA node IDs can be sparse. For example:
NUMA:
NUMA node(s): 6
NUMA node0 CPU(s): 80-159
NUMA node8 CPU(s): 0-79
NUMA node252 CPU(s):
NUMA node253 CPU(s):
NUMA node254 CPU(s):
NUMA node255 CPU(s):
That is, the possible/online NUMA node IDs are: 0, 8, 252, 253, 254, 255
In this case: num_possible_nodes() = 6
So memory is allocated for only 6 entries in current_path[]. However,
the array is later indexed using the actual NUMA node ID. As a result,
accesses such as:
head->current_path[8] or
head->current_path[252]
goes out of bounds, leading to the following KASAN splat:
==================================================================
BUG: KASAN: slab-out-of-bounds in nvme_mpath_revalidate_paths+0x22c/0x290 [nvme_core]
Write of size 8 at addr c00020003bda35b8 by task kworker/u641:2/1997
CPU: 1 UID: 0 PID: 1997 Comm: kworker/u641:2 Not tainted 7.1.0-rc5-dirty #14 PREEMPT(lazy)
Hardware name: 8335-GTH POWER9 0x4e1202 opal:skiboot-v6.5.3-35-g1851b2a06 PowerNV
Workqueue: async async_run_entry_fn
Call Trace:
[c000200037fa7510] [c0000000021c23d4] dump_stack_lvl+0x88/0xdc (unreliable)
[c000200037fa7540] [c0000000009fda90] print_report+0x22c/0x67c
[c000200037fa7630] [c0000000009fd508] kasan_report+0x108/0x220
[c000200037fa7740] [c0000000009fff48] __asan_store8+0xe8/0x120
[c000200037fa7760] [c008000018e76474] nvme_mpath_revalidate_paths+0x22c/0x290 [nvme_core]
[c000200037fa7800] [c008000018e6556c] nvme_update_ns_info+0x4a4/0x5e0 [nvme_core]
[c000200037fa7a50] [c008000018e66270] nvme_alloc_ns+0x6d8/0x1a70 [nvme_core]
[c000200037fa7c20] [c008000018e679fc] nvme_scan_ns+0x3f4/0x630 [nvme_core]
[c000200037fa7d10] [c00000000031f22c] async_run_entry_fn+0x9c/0x3a0
[c000200037fa7db0] [c0000000002fa544] process_one_work+0x414/0xa10
[c000200037fa7ec0] [c0000000002fbf00] worker_thread+0x320/0x640
[c000200037fa7f80] [c00000000030d0f8] kthread+0x278/0x290
[c000200037fa7fe0] [c00000000000ded8] start_kernel_thread+0x14/0x18
Allocated by task 1997 on cpu 1 at 35.928317s:
The buggy address belongs to the object at c00020003bda3000
which belongs to the cache kmalloc-rnd-15-2k of size 2048
The buggy address is located 16 bytes to the right of
allocated 1448-byte region [c00020003bda3000, c00020003bda35a8)
The buggy address belongs to the physical page:
Memory state around the buggy address:
c00020003bda3480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
c00020003bda3500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>c00020003bda3580: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
^
c00020003bda3600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
c00020003bda3680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
Fix this by allocating the flexible array using nr_node_ids instead
of num_possible_nodes(). Since nr_node_ids represents the maximum
possible NUMA node IDs, indexing current_path[] using numa_node_id()
becomes safe even on systems with sparse node IDs. |
| In the Linux kernel, the following vulnerability has been resolved:
nvme-pci: fix out-of-bounds access in nvme_setup_descriptor_pools
nvme_setup_descriptor_pools() indexes dev->descriptor_pools[] using the
numa_node forwarded from hctx->numa_node by its single caller,
nvme_init_hctx_common(). On a non-NUMA kernel hctx->numa_node is
NUMA_NO_NODE (-1). Because the parameter was declared 'unsigned', the
value becomes UINT_MAX and the index walks off the array (sized to
nr_node_ids), faulting during nvme_alloc_ns() and leaving the namespace
without a /dev node.
Reproduces on any NVMe controller probed by a CONFIG_NUMA=n kernel:
BUG: unable to handle page fault for address: ffff889101603d38
RIP: 0010:nvme_init_hctx_common+0x5a/0x190 [nvme]
Call Trace:
nvme_init_hctx+0x10/0x20 [nvme]
nvme_alloc_ns+0x9e/0xa10 [nvme_core]
nvme_scan_ns+0x301/0x3b0 [nvme_core]
nvme_scan_ns_async+0x23/0x30 [nvme_core]
Switch the parameter to int and fall back to node 0 when it is
NUMA_NO_NODE; node 0 is always present. |
| In the Linux kernel, the following vulnerability has been resolved:
md/raid10: reset read_slot when reusing r10bio for discard
put_all_bios() always drops devs[i].bio, but it only drops
devs[i].repl_bio when r10_bio->read_slot < 0. If discard reuses an
r10bio that was previously used for a read, read_slot can still be
non-negative, and discard cleanup can skip bio_put() on repl_bio.
Reset read_slot to -1 when preparing an r10bio for discard so the
replacement bio is always released correctly. |
| In the Linux kernel, the following vulnerability has been resolved:
nvdimm/btt: Handle preemption in BTT lane acquisition
BTT lanes serialize access to per-lane metadata and workspace state
during BTT I/O. The btt-check unit test reports data mismatches during
BTT writes due to a race in lane acquisition that can lead to silent
data corruption.
The existing lane model uses a spinlock together with a per-CPU
recursion count. That recursion model stopped being valid after BTT
lanes became preemptible: another task can run on the same CPU,
observe a non-zero recursion count, bypass locking, and use the same
lane concurrently.
BTT lanes are also held across arena_write_bytes() calls. That path
reaches nsio_rw_bytes(), which flushes writes with nvdimm_flush().
Some provider flush callbacks can sleep, making a spinlock the wrong
primitive for the lane lifetime.
Replace the spinlock-based recursion model with a dynamically
allocated per-lane mutex array and take the lane lock
unconditionally.
Add might_sleep() to catch any future atomic-context caller.
Found with the ndctl unit test btt-check.sh. |
| In the Linux kernel, the following vulnerability has been resolved:
configfs_lookup(): don't leave ->s_dentry dangling on failure
Normally ->s_dentry is cleared when dentry it's pointing to becomes
negative (on eviction, realistically). However, that only happens
if dentry gets to be positive in the first place; in case of inode
allocation failure dentry never becomes positive, so ->d_iput()
is not called at all.
We do part of what normally would've been done by configfs_d_iput()
(dropping the reference to configfs_dirent) manually, but we do
not clear ->s_dentry there. Sloppy as it is, it does not matter in
case of configfs_create_{dir,link}() - there configfs_dirent does
not survive dropping the sole reference to it.
However, for configfs_lookup() it *does* survive, with a dangling
pointer to soon to be freed dentry sitting it its ->s_dentry.
Subsequent getdents(2) in that directory will end up dereferencing
that pointer in order to pick the inode number. Use after free...
This is the minimal fix; the right approach is to set the linkage
between dentry and configfs_dirent only after we know that we have
an inode, but that takes more surgery and the bug had been there
since 2006, so... |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/nldev: Fix locking when accessing mr->pd
Sashiko points out that, due to rereg_mr, the PD is actually variable and
all the touches in nldev are racy.
Use mr->device instead of mr->pd->device.
Getting the PD restrack ID is more tricky. To avoid disturbing all the
happy paths, add an rdma_restrack_sync() operation which is sort of like
flush_workqueue() or synchronize_irq(): after it returns, all the old
nldev touches to the mr are gone and everything sees the new PD. This
makes it safe to reach into the PD pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
configfs: fix lockless traversals of ->s_children
Having the parent directory locked protects entries from removal
by another thread, but it does *not* protect cursors from being
moved around by lseek() - or freed, for that matter. |
| In the Linux kernel, the following vulnerability has been resolved:
ixgbe: do not configure xps for XDP queues
netif_set_xps_queue() should not be called for an XDP Tx queue, since such
queues are not netdev-exposed. On systems with number of CPUs >=64, on E610
adapter, netdev is configured with maximum number queue pairs being 63
(due to MSI-X assignment), but configuring XDP results in 64 XDP queues.
So, during XDP program load, when netif_set_xps_queue() is called for the
last XDP queue, we get a WARNING with a call trace and KASAN report
afterwards (if enabled).
[ 2012.699800] WARNING: net/core/dev.c:2854 at __netif_set_xps_queue+0x116a/0x1e40, CPU#36: xdpsock/103668
[...]
[ 2012.700029] RIP: 0010:__netif_set_xps_queue+0x116a/0x1e40
[ 2012.700035] Code: b6 34 06 48 89 f8 83 e0 07 83 c0 01 40 38 f0 7c 09 40 84 f6 0f 85 03 0a 00 00 0f b7 44 24 40 66 43 89 44 6a 18 e9 01 fb ff ff <0f> 0b e9 f2 ee ff ff 44 8b 44 24 44 45 85 c0 74 50 4d 85 e4 0f 84
[ 2012.700040] RSP: 0018:ffff8882369aeb28 EFLAGS: 00010246
[ 2012.700046] RAX: 0000000000000000 RBX: 000000000000003f RCX: 0000000000000000
[ 2012.700050] RDX: 1ffff1111da3d891 RSI: ffff888120e34250 RDI: ffff8888ed1ec488
[ 2012.700054] RBP: ffff888913281560 R08: 0000000000000000 R09: ffff8888ed1ec000
[ 2012.700058] R10: ffff8888a2e83180 R11: 0000000000000000 R12: 0000000000007fa8
[ 2012.700061] R13: 000000000000003f R14: ffff888120e34854 R15: ffff8889132817c8
[ 2012.700065] FS: 00007fc8ea9ff740(0000) GS:ffff88884cefe000(0000) knlGS:0000000000000000
[ 2012.700069] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2012.700073] CR2: 00007f81c8000020 CR3: 00000002299f8006 CR4: 00000000007726f0
[ 2012.700077] PKRU: 55555554
[ 2012.700080] Call Trace:
[ 2012.700084] <TASK>
[ 2012.700087] ? ktime_get+0x61/0x150
[ 2012.700097] ? usleep_range_state+0x133/0x1b0
[ 2012.700108] ? __pfx_usleep_range_state+0x10/0x10
[ 2012.700114] netif_set_xps_queue+0x31/0x50
[ 2012.700119] ixgbe_configure_tx_ring+0x472/0x920 [ixgbe]
[...]
[ 2012.700486] ixgbe_xdp+0x38f/0x750 [ixgbe]
[...]
[ 2012.701094] BUG: KASAN: slab-out-of-bounds in __netif_set_xps_queue+0x1ac5/0x1e40
[ 2012.701100] Write of size 4 at addr ffff88888d43cff8 by task xdpsock/103668
Skip XPS configuration for XDP Tx queues. |
| In the Linux kernel, the following vulnerability has been resolved:
NFSD: Handle layout stid in nfsd4_drop_revoked_stid()
nfsd4_drop_revoked_stid() has no SC_TYPE_LAYOUT case, so when a
client sends FREE_STATEID for an admin-revoked layout stid, the
default branch releases cl_lock and returns without unhashing or
releasing the stid. The stid remains in the IDR and on the
per-client list until the client is destroyed.
Remove the layout stid from the per-client list and call
nfs4_put_stid() to drop the creation reference. When the
refcount reaches zero, nfsd4_free_layout_stateid() handles the
remaining cleanup: cancelling the fence worker, removing from
the per-file list, and freeing the slab object. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Cancel special fields on map value recycle
Map update and delete paths currently call bpf_obj_free_fields() when a
value is being replaced or recycled. That makes field destruction depend
on the context of the update/delete operation. For tracing programs this
can include NMI context, where referenced kptr destructors, uptr
unpinning, and graph root destruction are not generally safe.
Introduce bpf_obj_cancel_fields() for the reusable-value path. It only
performs NMI-safe cleanup for timer, workqueue, and task_work fields.
Fields that need full destruction are left attached to the recycled value
and are destroyed by the final cleanup path instead.
Switch array and hashtab update/delete/recycle paths to this cancel
helper. Keep bpf_obj_free_fields() for final map destruction and for
bpf_mem_alloc destructors. Preallocated hashtabs do not have allocator
destructors, so teardown continues to walk the normal and extra elements
and fully destroy their fields.
This deliberately relaxes the eager-free semantics of map update/delete
for special fields. Programs that relied on a recycled map slot becoming
empty immediately after update/delete were relying on behavior that
cannot be implemented safely from every BPF execution context without
offloading arbitrary destructors.
There is a chance this change breaks programs making assumptions
regarding the eager freeing of fields. If so, we can relax semantics to
cancellation only when irqs_disabled() is true in the future. However,
theoretically, map values that get reused eagerly already have weaker
guarantees as parallel users can recreate freed fields before the new
element becomes visible again. |
| In the Linux kernel, the following vulnerability has been resolved:
vhost/vdpa: validate virtqueue index in mmap and fault paths
vhost_vdpa_mmap() and vhost_vdpa_fault() use vma->vm_pgoff as a
virtqueue index for get_vq_notification(), but they do not validate
that the index is smaller than v->nvqs.
The ioctl path already performs both a bounds check and
array_index_nospec(), but the mmap/fault path only checks that the
index fits in u16. This allows an out-of-range queue index to reach
driver-specific get_vq_notification() callbacks.
Fix this by extracting a unified vhost_vdpa_get_vq_notification()
helper that validates the queue index against v->nvqs and applies
array_index_nospec() before calling the driver callback. Both the
mmap and fault paths use this helper, and the bounds checking is
consolidated into a single location.
From source inspection, the most defensible impact is out-of-bounds
access in the callback path, potentially leading to invalid PFN
remaps and crash/DoS. |
| In the Linux kernel, the following vulnerability has been resolved:
vhost/net: complete zerocopy ubufs only once
vhost-net initializes one ubuf_info per outstanding zerocopy TX
descriptor and hands it to the backend socket. The networking stack may
then clone a zerocopy skb before all skb references are released. For
example, batman-adv fragmentation reaches skb_split(), which calls
skb_zerocopy_clone() and increments the same ubuf_info refcount.
vhost_zerocopy_complete() currently treats every ubuf callback as a
completed vhost descriptor. It dereferences ubuf->ctx, writes the
descriptor completion state, and drops the vhost_net_ubuf_ref even when
the callback only releases a cloned skb reference. A backend reset can
therefore wait for and free the vhost_net_ubuf_ref while another cloned
skb still carries the same ubuf_info. A later completion then
dereferences the freed ubufs pointer.
KASAN reports the stale completion as:
BUG: KASAN: slab-use-after-free in vhost_zerocopy_complete+0x1d7/0x1f0
BUG: KASAN: slab-use-after-free in vhost_zerocopy_complete+0x101/0x1f0
vhost_zerocopy_complete
skb_copy_ubufs
__dev_forward_skb2
veth_xmit
The freed object was allocated from vhost_net_ioctl() while setting the
backend and freed through kfree_rcu()/kvfree_rcu_bulk after backend
removal, while delayed skb completion still reached
vhost_zerocopy_complete().
Honor the generic ubuf_info refcount before touching vhost state, and run
the vhost descriptor completion only for the final ubuf reference. This
matches the msg_zerocopy_complete() ownership rule for cloned zerocopy
skbs. |