| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
drm/msm: don't tear down KMS twice when KMS init fails
When priv->kms_init() (mdp4_kms_init() / mdp5_kms_init()) fails partway
through, both display drivers already tear their KMS state down via
mdp4_destroy() / mdp5_kms_destroy() before returning the error. The
common error path in msm_drm_init() then runs msm_drm_uninit() ->
msm_drm_kms_uninit(), which tries to destroy the very same KMS a second
time, which causes a use-after-free crash.
Bring MDP4/MDP5 in line with the DPU driver whose dpu_kms_init() doesn't
perform error cleanup on the failure. Let the common path own the
cleanup, instead of freeing the KMS from their error paths.
The crash trace for the reference:
__lock_acquire from lock_acquire (kernel/locking/lockdep.c:5906 kernel/locking/lockdep.c:5863)
lock_acquire from touch_wq_lockdep_map (kernel/workqueue.c:4094 (discriminator 1))
touch_wq_lockdep_map from __flush_workqueue (kernel/workqueue.c:4136)
__flush_workqueue from msm_drm_kms_uninit (drivers/gpu/drm/msm/msm_kms.c:243 (discriminator 33))
msm_drm_kms_uninit from msm_drm_uninit (drivers/gpu/drm/msm/msm_drv.c:93)
msm_drm_uninit from msm_drm_init (drivers/gpu/drm/msm/msm_drv.c:184)
msm_drm_init from try_to_bring_up_aggregate_device (drivers/base/component.c:249 drivers/base/component.c:227)
try_to_bring_up_aggregate_device from __component_add (drivers/base/component.c:269 drivers/base/component.c:748)
__component_add from dsi_host_attach (drivers/gpu/drm/msm/dsi/dsi_host.c:1739)
dsi_host_attach from mipi_dsi_attach (drivers/gpu/drm/drm_mipi_dsi.c:383)
mipi_dsi_attach from sharp_nt_panel_probe (drivers/gpu/drm/panel/panel-sharp-ls043t1le01.c:247)
Patchwork: https://patchwork.freedesktop.org/patch/742068/ |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: cfg80211: stop PMSR before P2P and NAN teardown
PMSR request teardown must abort active measurements while the
wireless_dev is still present in the driver. cfg80211_leave_locked() and
cfg80211_stop_pd() already do this before invoking the driver's stop
callback, but cfg80211_stop_p2p_device() and cfg80211_stop_nan() do not.
Those helpers are also called directly by nl80211, rfkill shutdown, and
wireless_dev unregister paths. If one of these paths stops a P2P device
or NAN interface with a pending request, it removes the mac80211
subinterface from the driver first. Subsequent request cleanup cannot
reach the lower driver's abort callback, but cfg80211 frees the request
regardless. Driver state can then retain a stale request and use it when
it later reports a result.
Call cfg80211_pmsr_wdev_down() before stopping the P2P device or NAN
interface. This keeps lower-driver request state and cfg80211 request
ownership in sync for all of the helpers' callers. |
| In the Linux kernel, the following vulnerability has been resolved:
serial: core: do fallible allocations before the console can be registered
serial_core_add_one_port() allocates uport->tty_groups after
uart_configure_port(), which may register the console. If the allocation
fails, the driver unwinds the port while its console remains registered.
The earlier uport->name allocation has a related failure path that leaves
state->uart_port linked to a port being freed.
Failslab reproduced a NULL dereference in PL011 console output and a KASAN
use-after-free in i.MX console output after failed binds.
Allocate the name and tty_groups before linking the port and configuring
it. Reserve space for the optional driver attribute group because
config_port() may populate uport->attr_group during configuration. |
| In the Linux kernel, the following vulnerability has been resolved:
serial: core: clear freed pointers on uart_register_driver() failure
uart_register_driver() leaves drv->state pointing to freed memory when
tty_alloc_driver() fails. If tty_register_driver() fails, drv->tty_driver
also retains a pointer after its reference is dropped.
Drivers that use drv->state as an "already registered" flag can then skip
registration on the next probe and pass the freed state to
uart_add_one_port().
This issue was found with failslab on QEMU's raspi1ap board by
failing registration and binding the PL011 port again.
Clear both pointers on their failure paths, as uart_unregister_driver()
already does. |
| In the Linux kernel, the following vulnerability has been resolved:
blk-cgroup: fix race between policy activation and blkg destruction
When switching an IO scheduler on a block device, blkcg_activate_policy()
allocates blkg_policy_data (pd) for all blkgs attached to the queue.
However, blkcg_activate_policy() may race with concurrent blkcg deletion,
leading to use-after-free and memory leak issues.
The use-after-free occurs in the following race:
T1 (blkcg_activate_policy):
- Successfully allocates pd for blkg1 (loop0->queue, blkcgA)
- Fails to allocate pd for blkg2 (loop0->queue, blkcgB)
- Enters the enomem rollback path to release blkg1 resources
T2 (blkcg deletion):
- blkcgA is deleted concurrently
- blkg1 is freed via blkg_free_workfn()
- blkg1->pd is freed
T1 (continued):
- Rollback path accesses blkg1->pd->online after pd is freed
- Triggers use-after-free
In addition, blkg_free_workfn() frees pd before removing the blkg from
q->blkg_list. This allows blkcg_activate_policy() to allocate a new pd
for a blkg that is being destroyed, leaving the newly allocated pd
unreachable when the blkg is finally freed.
Fix these races by extending blkcg_mutex coverage to serialize
blkcg_activate_policy() rollback and blkg destruction, ensuring pd
lifecycle is synchronized with blkg list visibility. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: validate inline xattrs during inode block validation
Patch series "ocfs2: validate xattr entry bounds", v7.
This series validates OCFS2 xattr entry name/value bounds when xattr
metadata is read and validated, before getxattr() or listxattr() can walk
out-of-range entry arrays or offsets from corrupted metadata.
This patch (of 2):
ocfs2_validate_inode_block() verifies a dinode before OCFS2 users walk
metadata from it, but inline xattr metadata is still checked only in
operation-specific consumers. The existing ibody lookup helper validates
inline header placement and entry count, but inode block validation does
not reject entry name/value bounds.
Add a flat xattr entry validator and call it from inode block validation
for inline xattrs. Keep the operation paths on their existing
header/count lookup checks; the full entry bounds check now runs when the
inode block is validated at read time.
Reject corrupted inline xattr metadata before ocfs2_xattr_ibody_get() or
listxattr() can walk past the inline storage.
Validation reproduced this kernel report:
BUG: KASAN: use-after-free in ocfs2_xattr_find_entry+0x5a/0x170
Read of size 2 at addr ffff8881242a2000 by task python3/529
Call Trace:
dump_stack_lvl+0x66/0xa0
print_report+0xce/0x630
kasan_report+0xe0/0x110
ocfs2_xattr_find_entry+0x5a/0x170
ocfs2_xattr_get_nolock+0x20a/0x820
ocfs2_xattr_get+0x10c/0x1e0
__vfs_getxattr+0xe2/0x130
vfs_getxattr+0x185/0x1b0 |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/erdma: Hold QP references for AE and CM processing
AE QP fatal events and iWARP CM paths load QPs from dev->qp_xa
and then use or reference them outside the xarray lock.
erdma_destroy_qp() can drop the destroy-path reference and free QP
resources while such a lookup is in flight.
Add erdma_qp_get_by_qpn() to acquire a kref under the xarray
lock with kref_get_unless_zero(). Remove the QP from the xarray
before dropping the destroy-path reference so no new lookup can acquire
it while destruction waits for existing users. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: o2hb: quiesce negotiate handlers and timeout work
Heartbeat regions publish struct o2hb_region as the private data for the
NEGO_TIMEOUT and NEGO_APPROVE o2net handlers as soon as make_item()
creates the configfs region. The approve handler can call
o2hb_arm_timeout(), so a peer can touch the region timeout work before
dev_store() has finished building the heartbeat runtime, or after teardown
has started to shut that runtime back down.
The final configfs put also has to keep reg alive until the last in-flight
o2net callback drops its handler reference.
o2net_unregister_handler_list() blocks future handler lookups, but it does
not wait for sc_rx_work that already passed o2net_handler_get(). That
drain needs to cover local listener teardown as well, where the o2net
ordered workqueue may already be inside destroy_workqueue().
Fix the lifetime rule in both directions. Initialize the region delayed
works before publishing reg through the o2net handler table, keep new or
stopping regions non-armable with hr_stopping, and quiesce both delayed
works on failed-start and teardown paths even when no heartbeat thread is
left to call o2hb_disarm_timeout(). Then unregister handlers before
tearing down handler-visible region state and make the drain wait for the
active or destroying o2net ordered workqueue before release frees reg.
The buggy scenario involves two paths, with each column showing the order
within that path:
region lifecycle: late negotiate callback:
1. make_item() registers the 1. o2net_process_message() gets a
region handlers before heartbeat handler for reg.
dev_store() has built a 2. The callback runs after the lookup
runnable heartbeat context. lock is dropped and dereferences reg.
2. A failed start or rmdir 3. An approve or timeout path tries to
stops the heartbeat thread, queue reg's delayed work, or release
quiesces existing work, and races the callback body after handler
drops the final configfs ref. unregister.
3. region_release() must drain 4. The callback or delayed work can
handler-visible o2net rx work outlive reg unless lifecycle code
before freeing reg. keeps the region non-armable and
drains the active-or-destroying
o2net workqueue.
Validation reproduced this kernel report:
KASAN slab-use-after-free in __run_timers+0x22c/0x5b0
Write of size 8
Call trace:
dump_stack_lvl+0x66/0xa0
print_report+0xce/0x630
__run_timers+0x22c/0x5b0
kasan_report+0xe0/0x110
_raw_spin_unlock_irqrestore+0x27/0x60
try_to_wake_up+0x191/0xf70
timer_expire_remote+0xae/0xf0
run_timer_softirq+0x19b/0x1a0
handle_softirqs+0x156/0x660
__irq_exit_rcu+0xc4/0x160
irq_exit_rcu+0xe/0x20
sysvec_apic_timer_interrupt+0x6c/0x80
asm_sysvec_apic_timer_interrupt+0x1a/0x20
Allocated by task stack:
kasan_save_stack+0x33/0x60
kasan_save_track+0x14/0x30
__kasan_kmalloc+0xaa/0xb0
o2hb_heartbeat_group_make_item+0x3c/0x600 |
| In the Linux kernel, the following vulnerability has been resolved:
module/dups: Fix use-after-free in kmod_dup_req lifetime handling
The kmod dups code uses RCU to ensure that a kmod_dup_req instance is freed
only after it is no longer referenced. When releasing an instance, the
kmod_dup_request_delete() function removes the kmod_dup_req from the
dup_kmod_reqs list, waits via synchronize_rcu() and finally frees it.
However, this doesn't work correctly because parallel users referencing the
instance in kmod_dup_request_exists_wait() don't enter an RCU read-side
critical section. This can result in a use-after-free.
The kmod_dup_request_exists_wait() function may need to hold a valid
reference to a kmod_dup_req instance across a blocking wait until the
corresponding modprobe command completes. This makes it unsuitable for RCU.
Fix the issue by changing the lifecycle management of kmod_dup_req to use
reference counting. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: zoned: don't clobber the extent buffer when zeroing it out
On a zoned filesystem a freed-but-still-dirty tree block is written out
as zeros (EXTENT_BUFFER_ZONED_ZEROOUT) only to keep the zone write
pointer advancing. btree_csum_one_bio() implemented this by memzeroing
the extent buffer's own folios before submission.
That destroys the in-memory buffer while it may still be referenced. In
particular btrfs_free_tree_block() can run on it afterwards and reads
the header to add a delayed reference; once the header has been zeroed
it frees bytenr 0 and corrupts the extent tree (the
btrfs_header_bytenr(buf) != 0 ASSERT in btrfs_free_tree_block(), or an
"unable to find ref" abort). It is flaky and reproduces under fsstress,
e.g. generic/461 and generic/013.
Write the zeros to disk from the shared zero page instead and leave the
extent buffer content untouched, so any later reference - including the
delayed reference from btrfs_free_tree_block() - still sees a valid
header. end_bbio_meta_write() now clears writeback on the buffer's own
folios, as the bio no longer carries them. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind
hci_conn::l2cap_data is accessed without locks in l2cap_disconn_ind via
hci_conn_timeout (disc_work) -> hci_proto_disconn_ind ->
l2cap_disconn_ind. This is UAF if the l2cap_conn is deleted
concurrently.
disc_work is disabled sync in hci_conn_del(), so we cannot take
hci_dev_lock in disc_work.
Fix by using proto_lock to guard l2cap_data, in addition to hdev->lock
which is held in other access paths. |
| In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Flush context cache with correct SID when tearing down aliases
domain_context_clear_one() and device_pasid_table_teardown() are both
invoked once per DMA alias of a device. Each function locates the context
entry using the bus/devfn pair provided by the pci_for_each_dma_alias()
callback, then calls intel_context_flush_no_pasid(), which constructs a
device-selective context-cache invalidation from info->bus and
info->devfn (that is, always the requester ID of the device itself).
As a result, for every alias other than the device’s own RID, the context
entry that was just cleared in memory is never invalidated in the context
cache. Hardware may continue using that stale cached entry. In the
scalable-mode teardown path, intel_pasid_free_table() can then free the
PASID directory still referenced by that stale entry, allowing the IOMMU
to walk freed memory.
Fix this by passing the source ID of the entry being torn down to
intel_context_flush_no_pasid(), instead of deriving it from @info. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: validate DIO orphan slot during inode read
[BUG]
A corrupted append-DIO dinode (high byte at offset 0xa1
corrupted from 0 to 1) can carry an i_dio_orphaned_slot
outside the mounted filesystem slot range and trigger a
use-after-free error:
BUG: KASAN: slab-use-after-free in ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102
Read of size 8 at addr ffff88800b767c00 by task kworker/u8:3/85
Call Trace:
...
ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102
ocfs2_wipe_inode+0x292/0xf70 fs/ocfs2/inode.c:840
ocfs2_delete_inode fs/ocfs2/inode.c:1155 [inline]
ocfs2_evict_inode+0x6c9/0x1170 fs/ocfs2/inode.c:1295
evict+0x38e/0x8f0 fs/inode.c:810
iput_final fs/inode.c:1914 [inline]
iput fs/inode.c:1966 [inline]
iput+0x55b/0x8b0 fs/inode.c:1926
ocfs2_recover_orphans+0x610/0xe40 fs/ocfs2/journal.c:2374
ocfs2_complete_recovery+0x5af/0xd00 fs/ocfs2/journal.c:1373
...
[CAUSE]
ocfs2_del_inode_from_orphan() uses i_dio_orphaned_slot to index the
slot-local system inode cache. The dinode validator does not check
this active slot, so an out-of-range value produces an invalid cache
entry pointer that is dereferenced as an inode pointer.
[FIX]
Reject an active i_dio_orphaned_slot outside the slot range during
dinode validation, before DIO orphan recovery can consume it. |
| In the Linux kernel, the following vulnerability has been resolved:
apparmor: fix deadlock in complain-mode change_hat
The use of change_hat when in complain mode can cause a deadlock
when the hat doesn't exist and a new learning profile is created
for the missing profile. This is because change_hat() has taken
the lock to search the hat list and creating the new learning
profile needs to take the lock to add it to the list.
From the bug report:
Originally found in 7.0.0 in LTS ubuntu 26.04 with pam_apparmor + su
in complain mode set to change hats. Then verified in newest
available vanilla kernel I've compiled to see if still present:
7.2-rc7 vanilla -> affected
checked also some other kernels:
6.18.44 vanilla -> affected
6.12.95 with debian patches -> unaffected
On systems without bug (for example 6.12.95 debian) it just prints:
aa_change_hat rc=0
On systems with bug, the executable always hangs, prints nothing and
becomes unkillable. (And once stuck this way, it will cause any
further hat changes to also cause the changing process to get stuck)
Then in syslog you can find hint about cause:
kernel: INFO: task hat:3409 blocked for more than 483 seconds.
kernel: Not tainted 7.2.0-rc7 #1
kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kernel: task:hat state:D stack:0 pid:3409 tgid:3409 ppid:2605 task_flags:0x400000 flags:0x00080800
kernel: Call Trace:
kernel: <TASK>
kernel: __schedule+0x48f/0xfe0
kernel: schedule+0x27/0xa0
kernel: schedule_preempt_disabled+0x15/0x30
kernel: __mutex_lock.constprop.0+0x569/0xa10
kernel: aa_new_learning_profile+0x15f/0x210
kernel: build_change_hat+0x19f/0x3b0
kernel: change_hat.isra.0+0x5dd/0xd60
kernel: aa_change_hat+0x2f3/0x710
kernel: aa_setprocattr_changehat+0x121/0x1f0
kernel: do_setattr+0x28c/0x340
kernel: apparmor_setselfattr+0x20/0x50
kernel: security_setselfattr+0xf6/0x110
kernel: __x64_sys_lsm_set_self_attr+0x53/0x90
kernel: do_syscall_64+0xdd/0x5e0
kernel: ? __mod_memcg_lruvec_state+0xfd/0x260
kernel: ? lruvec_stat_mod_folio+0x8d/0xd0
kernel: ? __folio_mod_stat+0x2d/0x90
kernel: ? map_anon_folio_pte_nopf+0xd1/0x1f0
kernel: ? do_anonymous_page+0x184/0xa10
kernel: ? __handle_mm_fault+0x805/0x870
kernel: ? count_memcg_events+0xef/0x230
kernel: ? handle_mm_fault+0x1f0/0x2f0
kernel: ? do_user_addr_fault+0x2bb/0x7b0
kernel: ? do_syscall_64+0x94/0x5e0
kernel: ? exc_page_fault+0x75/0x160
kernel: entry_SYSCALL_64_after_hwframe+0x76/0x7e
kernel: RIP: 0033:0x7f815e134c8d
kernel: RSP: 002b:00007fff6df94ea8 EFLAGS: 00000246 ORIG_RAX: 00000000000001cc
kernel: RAX: ffffffffffffffda RBX: 0000556d8c81d040 RCX: 00007f815e134c8d
kernel: RDX: 0000000000000046 RSI: 0000556d8c81d040 RDI: 0000000000000064
kernel: RBP: 00007fff6df94ef0 R08: 00007f815e212ac8 R09: 000000000000000c
kernel: R10: 0000000000000000 R11: 0000000000000246 R12: 0000556d8c81d010
kernel: R13: 0000000000000026 R14: 0000000000000046 R15: 0000000000000064
kernel: </TASK>
kernel: INFO: task hat:3409 is blocked on a mutex likely owned by task hat:3409.
To fix the issue, lift the locking out of the core of
aa_new_learning_profile(), introduce a wrapper function that takes the
lock where needed, and have build_change_hat() call the core function
that no longer takes the lock.
In addition fix 4 other issues introduced by commit
32e92764d6f8d ("apparmor: grab ns lock and refresh when looking up changehat child profiles")
- aa_get_profile_rcu() was replaced-by: aa_get_profile without the
accompanying rcu_dereference_protected()
- an extra aa_get_label(label) was introduced at the start of
change_hat() without an accompanying aa_put_label() causing a
reference count leak.
- a reference count leak was introduced in the label_is_stale(label)
case, where the newest profile would be leaked instead of the
label passed to the function.
- a potential UAF when the lookup walks up the tree with new_ns != ns
the new label refere
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: defer publishing granted locks to prevent UAF/double-free race
In smb2_lock(), mid-batch granted locks are published to connection-wide
(conn->lock_list) and file-wide (fp->lock_list) lists immediately upon
vfs_lock_file() success, while also remaining tracked on the stack-local
rollback_list.
If a subsequent element in the same SMB2_LOCK request array fails
validation or execution, the thread jumps to out: and walks
rollback_list to undo previously granted locks. However, because the
granted lock was already published to conn->lock_list, a concurrent
UNLOCK request on the same connection can find the lock object and
kfree() it before the rollback loop executes.
When the granting thread subsequently walks rollback_list, it
dereferences and frees the already-freed ksmbd_lock structure, resulting
in a Use-After-Free and Double-Free (on both ksmbd_lock and struct
file_lock).
Fix this by deferring the publication of granted locks to
conn->lock_list and fp->lock_list until after the entire array of lock
elements has been processed without error. Mid-batch grants remain
tracked exclusively on the request-local rollback_list until the whole
batch succeeds, eliminating the race window. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: safely discard unregistered deferred locks
When vfs_lock_file() defers a lock, smb2_lock() puts its ksmbd_lock on
rollback_list before allocating and registering the asynchronous work.
If either operation fails, rollback assumes that smb_lock->conn is
initialized and dereferences NULL. The deferred file_lock also remains
linked into the VFS blocked-lock state while it is freed.
Keep the lock off rollback_list until async setup succeeds. On setup
failures, explicitly unblock and wake the deferred lock before freeing it
and its ksmbd wrapper. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: detach blocked lock requests before freeing
A file_lock retained by ksmbd for byte-range lock bookkeeping can still
be part of the VFS blocked-request graph. In particular, the VFS can
chain a new waiter below an already blocked request through
flc_blocked_requests. The ksmbd_file reference count does not cover that
graph.
Both __ksmbd_close_fd() and the cross-request unlock path free these
retained file_lock objects directly. If a dependent waiter is still
attached, locks_release_private() hits
BUG_ON(!list_empty(&flc->flc_blocked_requests)). The same lifetime
mismatch can leave a freed ksmbd_lock reachable through its request-local
llist.
Detach the file_lock from the blocked-request graph before freeing it in
the close, cross-request unlock, and rollback paths. locks_delete_block()
also wakes requests chained below the object. Remove llist when a
completed lock is published so a globally visible ksmbd_lock no longer
points into the submitting worker's stack. |
| In the Linux kernel, the following vulnerability has been resolved:
net: add missing ref_tracker_dir_exit() to alloc_netdev_mqs()
sashiko is reporting that trying to read /sys/kernel/debug/ref_tracker/*
causes use-afer-free crash when either alloc_percpu() or dev_addr_init()
in alloc_netdev_mqs() failed, for commit 4d92b95ff2f9 ("net: add net device
refcount tracker infrastructure") added ref_tracker_dir_exit() to only
free_netdev() path. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: mtpav: shut down output timer before card teardown
snd_mtpav_output_timer() rearms chip->timer while holding
chip->spinlock and accesses the card-private mtpav state.
snd_mtpav_free() currently takes the same lock and calls
timer_delete() when the timer is active. This only removes a
pending timer; it does not wait for a callback that is already
running and does not prevent the callback from rearming the timer.
A callback running on another CPU can therefore continue after
snd_mtpav_free() releases the lock and access the card-private
state while the card is being torn down. It can also rearm the
timer after timer_delete() has returned.
Call timer_shutdown_sync() without holding chip->spinlock. This
waits for any running callback to finish and prevents further
rearming before the card-private mtpav state is released. |
| In the Linux kernel, the following vulnerability has been resolved:
ip6mr: do not clone dst in ip6mr_cache_report()
IPv6 input attaches a non-refcounted (NOREF) dst to skbs under RCU.
When an ingress multicast packet misses MFC lookup,
ip6mr_cache_unresolved() places the skb onto the unresolved queue,
escaping the receive-side RCU grace period.
If the underlying route is deleted and freed, and the MFC queue is later
resolved with a wrong parent interface, ip6_mr_forward() invokes
ip6mr_cache_report(..., MRT6MSG_WRONGMIF), which executes
dst_clone(skb_dst(pkt)) on the freed dst entry, triggering a slab
use-after-free.
Report packets queued to mroute6_sk (a raw socket) and netlink
notifications do not require an attached dst entry.
Fix this by:
1. Removing dst_clone() in ip6mr_cache_report() and ensuring report skbs
do not hold a dst.
2. Dropping skb_dst before queuing unresolved skbs in
ip6mr_cache_unresolved(), matching the fact that multicast
forwarding resolves outgoing routes anew via ip6_route_output(). |