| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| The UpMenu – Online ordering for restaurants plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'lang' attribute of the 'upmenu-menu' shortcode in all versions up to, and including, 3.1. This is due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: correctly decode TTLM with default link map
TID-To-Link Mapping (TTLM) elements do not contain any link mapping
presence indicator if a default mapping is used and parsing needs to be
skipped.
Note that access points should not explicitly report an advertised TTLM
with a default mapping as that is the implied mapping if the element is
not included, this is even the case when switching back to the default
mapping. However, mac80211 would incorrectly parse the frame and would
also read one byte beyond the end of the element. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: do not strictly require dirty metadata threshold for metadata writepages
[BUG]
There is an internal report that over 1000 processes are
waiting at the io_schedule_timeout() of balance_dirty_pages(), causing
a system hang and trigger a kernel coredump.
The kernel is v6.4 kernel based, but the root problem still applies to
any upstream kernel before v6.18.
[CAUSE]
From Jan Kara for his wisdom on the dirty page balance behavior first.
This cgroup dirty limit was what was actually playing the role here
because the cgroup had only a small amount of memory and so the dirty
limit for it was something like 16MB.
Dirty throttling is responsible for enforcing that nobody can dirty
(significantly) more dirty memory than there's dirty limit. Thus when
a task is dirtying pages it periodically enters into balance_dirty_pages()
and we let it sleep there to slow down the dirtying.
When the system is over dirty limit already (either globally or within
a cgroup of the running task), we will not let the task exit from
balance_dirty_pages() until the number of dirty pages drops below the
limit.
So in this particular case, as I already mentioned, there was a cgroup
with relatively small amount of memory and as a result with dirty limit
set at 16MB. A task from that cgroup has dirtied about 28MB worth of
pages in btrfs btree inode and these were practically the only dirty
pages in that cgroup.
So that means the only way to reduce the dirty pages of that cgroup is
to writeback the dirty pages of btrfs btree inode, and only after that
those processes can exit balance_dirty_pages().
Now back to the btrfs part, btree_writepages() is responsible for
writing back dirty btree inode pages.
The problem here is, there is a btrfs internal threshold that if the
btree inode's dirty bytes are below the 32M threshold, it will not
do any writeback.
This behavior is to batch as much metadata as possible so we won't write
back those tree blocks and then later re-COW them again for another
modification.
This internal 32MiB is higher than the existing dirty page size (28MiB),
meaning no writeback will happen, causing a deadlock between btrfs and
cgroup:
- Btrfs doesn't want to write back btree inode until more dirty pages
- Cgroup/MM doesn't want more dirty pages for btrfs btree inode
Thus any process touching that btree inode is put into sleep until
the number of dirty pages is reduced.
Thanks Jan Kara a lot for the analysis of the root cause.
[ENHANCEMENT]
Since kernel commit b55102826d7d ("btrfs: set AS_KERNEL_FILE on the
btree_inode"), btrfs btree inode pages will only be charged to the root
cgroup which should have a much larger limit than btrfs' 32MiB
threshold.
So it should not affect newer kernels.
But for all current LTS kernels, they are all affected by this problem,
and backporting the whole AS_KERNEL_FILE may not be a good idea.
Even for newer kernels I still think it's a good idea to get
rid of the internal threshold at btree_writepages(), since for most cases
cgroup/MM has a better view of full system memory usage than btrfs' fixed
threshold.
For internal callers using btrfs_btree_balance_dirty() since that
function is already doing internal threshold check, we don't need to
bother them.
But for external callers of btree_writepages(), just respect their
requests and write back whatever they want, ignoring the internal
btrfs threshold to avoid such deadlock on btree inode dirty page
balancing. |
| In the Linux kernel, the following vulnerability has been resolved:
mptcp: fix race in mptcp_pm_nl_flush_addrs_doit()
syzbot and Eulgyu Kim reported crashes in mptcp_pm_nl_get_local_id()
and/or mptcp_pm_nl_is_backup()
Root cause is list_splice_init() in mptcp_pm_nl_flush_addrs_doit()
which is not RCU ready.
list_splice_init_rcu() can not be called here while holding pernet->lock
spinlock.
Many thanks to Eulgyu Kim for providing a repro and testing our patches. |
| The Smart Forms plugin for WordPress is vulnerable to unauthorized access of data due to a missing capability check on the 'rednao_smart_forms_get_campaigns' AJAX action in all versions up to, and including, 2.6.99. This makes it possible for authenticated attackers, with Subscriber-level access and above, to retrieve donation campaign data including campaign IDs and names. |
| The AMP Enhancer – Compatibility Layer for Official AMP Plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the AMP Custom CSS setting in all versions up to, and including, 1.0.49 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with Administrator-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled. |
| The Magic Login Mail or QR Code plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 2.05. This is due to the plugin storing the magic login QR code image with a predictable, static filename (QR_Code.png) in the publicly accessible WordPress uploads directory during the email sending process. The file is only deleted after wp_mail() completes, creating an exploitable race condition window. This makes it possible for unauthenticated attackers to trigger a login link request for any user, including administrators, and then exploit the race condition between QR code file creation and deletion to obtain the login URL encoded in the QR code, thereby gaining unauthorized access to the targeted user's account. |
| In the Linux kernel, the following vulnerability has been resolved:
io_uring/io-wq: check IO_WQ_BIT_EXIT inside work run loop
Currently this is checked before running the pending work. Normally this
is quite fine, as work items either end up blocking (which will create a
new worker for other items), or they complete fairly quickly. But syzbot
reports an issue where io-wq takes seemingly forever to exit, and with a
bit of debugging, this turns out to be because it queues a bunch of big
(2GB - 4096b) reads with a /dev/msr* file. Since this file type doesn't
support ->read_iter(), loop_rw_iter() ends up handling them. Each read
returns 16MB of data read, which takes 20 (!!) seconds. With a bunch of
these pending, processing the whole chain can take a long time. Easily
longer than the syzbot uninterruptible sleep timeout of 140 seconds.
This then triggers a complaint off the io-wq exit path:
INFO: task syz.4.135:6326 blocked for more than 143 seconds.
Not tainted syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.135 state:D stack:26824 pid:6326 tgid:6324 ppid:5957 task_flags:0x400548 flags:0x00080000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121
io_wq_exit_workers io_uring/io-wq.c:1328 [inline]
io_wq_put_and_exit+0x271/0x8a0 io_uring/io-wq.c:1356
io_uring_clean_tctx+0x10d/0x190 io_uring/tctx.c:203
io_uring_cancel_generic+0x69c/0x9a0 io_uring/cancel.c:651
io_uring_files_cancel include/linux/io_uring.h:19 [inline]
do_exit+0x2ce/0x2bd0 kernel/exit.c:911
do_group_exit+0xd3/0x2a0 kernel/exit.c:1112
get_signal+0x2671/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x8c/0x540 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa02738f749
RSP: 002b:00007fa0281ae0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fa0275e6098 RCX: 00007fa02738f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fa0275e6098
RBP: 00007fa0275e6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa0275e6128 R14: 00007fff14e4fcb0 R15: 00007fff14e4fd98
There's really nothing wrong here, outside of processing these reads
will take a LONG time. However, we can speed up the exit by checking the
IO_WQ_BIT_EXIT inside the io_worker_handle_work() loop, as syzbot will
exit the ring after queueing up all of these reads. Then once the first
item is processed, io-wq will simply cancel the rest. That should avoid
syzbot running into this complaint again. |
| In the Linux kernel, the following vulnerability has been resolved:
ice: add missing ice_deinit_hw() in devlink reinit path
devlink-reload results in ice_init_hw failed error, and then removing
the ice driver causes a NULL pointer dereference.
[ +0.102213] ice 0000:ca:00.0: ice_init_hw failed: -16
...
[ +0.000001] Call Trace:
[ +0.000003] <TASK>
[ +0.000006] ice_unload+0x8f/0x100 [ice]
[ +0.000081] ice_remove+0xba/0x300 [ice]
Commit 1390b8b3d2be ("ice: remove duplicate call to ice_deinit_hw() on
error paths") removed ice_deinit_hw() from ice_deinit_dev(). As a result
ice_devlink_reinit_down() no longer calls ice_deinit_hw(), but
ice_devlink_reinit_up() still calls ice_init_hw(). Since the control
queues are not uninitialized, ice_init_hw() fails with -EBUSY.
Add ice_deinit_hw() to ice_devlink_reinit_down() to correspond with
ice_init_hw() in ice_devlink_reinit_up(). |
| In the Linux kernel, the following vulnerability has been resolved:
bonding: provide a net pointer to __skb_flow_dissect()
After 3cbf4ffba5ee ("net: plumb network namespace into __skb_flow_dissect")
we have to provide a net pointer to __skb_flow_dissect(),
either via skb->dev, skb->sk, or a user provided pointer.
In the following case, syzbot was able to cook a bare skb.
WARNING: net/core/flow_dissector.c:1131 at __skb_flow_dissect+0xb57/0x68b0 net/core/flow_dissector.c:1131, CPU#1: syz.2.1418/11053
Call Trace:
<TASK>
bond_flow_dissect drivers/net/bonding/bond_main.c:4093 [inline]
__bond_xmit_hash+0x2d7/0xba0 drivers/net/bonding/bond_main.c:4157
bond_xmit_hash_xdp drivers/net/bonding/bond_main.c:4208 [inline]
bond_xdp_xmit_3ad_xor_slave_get drivers/net/bonding/bond_main.c:5139 [inline]
bond_xdp_get_xmit_slave+0x1fd/0x710 drivers/net/bonding/bond_main.c:5515
xdp_master_redirect+0x13f/0x2c0 net/core/filter.c:4388
bpf_prog_run_xdp include/net/xdp.h:700 [inline]
bpf_test_run+0x6b2/0x7d0 net/bpf/test_run.c:421
bpf_prog_test_run_xdp+0x795/0x10e0 net/bpf/test_run.c:1390
bpf_prog_test_run+0x2c7/0x340 kernel/bpf/syscall.c:4703
__sys_bpf+0x562/0x860 kernel/bpf/syscall.c:6182
__do_sys_bpf kernel/bpf/syscall.c:6274 [inline]
__se_sys_bpf kernel/bpf/syscall.c:6272 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6272
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 |
| The Media Library Folders plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 8.3.6 via the delete_maxgalleria_media() and maxgalleria_rename_image() functions due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with Author-level access and above, to delete or rename attachments owned by other users (including administrators). The rename flow also deletes all postmeta for the target attachment, causing data loss. |
| In the Linux kernel, the following vulnerability has been resolved:
igc: Reduce TSN TX packet buffer from 7KB to 5KB per queue
The previous 7 KB per queue caused TX unit hangs under heavy
timestamping load. Reducing to 5 KB avoids these hangs and matches
the TSN recommendation in I225/I226 SW User Manual Section 7.5.4.
The 8 KB "freed" by this change is currently unused. This reduction
is not expected to impact throughput, as the i226 is PCIe-limited
for small TSN packets rather than TX-buffer-limited. |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: annotate data-race in ndisc_router_discovery()
syzbot found that ndisc_router_discovery() could read and write
in6_dev->ra_mtu without holding a lock [1]
This looks fine, IFLA_INET6_RA_MTU is best effort.
Add READ_ONCE()/WRITE_ONCE() to document the race.
Note that we might also reject illegal MTU values
(mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) in a future patch.
[1]
BUG: KCSAN: data-race in ndisc_router_discovery / ndisc_router_discovery
read to 0xffff888119809c20 of 4 bytes by task 25817 on cpu 1:
ndisc_router_discovery+0x151d/0x1c90 net/ipv6/ndisc.c:1558
ndisc_rcv+0x2ad/0x3d0 net/ipv6/ndisc.c:1841
icmpv6_rcv+0xe5a/0x12f0 net/ipv6/icmp.c:989
ip6_protocol_deliver_rcu+0xb2a/0x10d0 net/ipv6/ip6_input.c:438
ip6_input_finish+0xf0/0x1d0 net/ipv6/ip6_input.c:489
NF_HOOK include/linux/netfilter.h:318 [inline]
ip6_input+0x5e/0x140 net/ipv6/ip6_input.c:500
ip6_mc_input+0x27c/0x470 net/ipv6/ip6_input.c:590
dst_input include/net/dst.h:474 [inline]
ip6_rcv_finish+0x336/0x340 net/ipv6/ip6_input.c:79
...
write to 0xffff888119809c20 of 4 bytes by task 25816 on cpu 0:
ndisc_router_discovery+0x155a/0x1c90 net/ipv6/ndisc.c:1559
ndisc_rcv+0x2ad/0x3d0 net/ipv6/ndisc.c:1841
icmpv6_rcv+0xe5a/0x12f0 net/ipv6/icmp.c:989
ip6_protocol_deliver_rcu+0xb2a/0x10d0 net/ipv6/ip6_input.c:438
ip6_input_finish+0xf0/0x1d0 net/ipv6/ip6_input.c:489
NF_HOOK include/linux/netfilter.h:318 [inline]
ip6_input+0x5e/0x140 net/ipv6/ip6_input.c:500
ip6_mc_input+0x27c/0x470 net/ipv6/ip6_input.c:590
dst_input include/net/dst.h:474 [inline]
ip6_rcv_finish+0x336/0x340 net/ipv6/ip6_input.c:79
...
value changed: 0x00000000 -> 0xe5400659 |
| In the Linux kernel, the following vulnerability has been resolved:
netdevsim: fix a race issue related to the operation on bpf_bound_progs list
The netdevsim driver lacks a protection mechanism for operations on the
bpf_bound_progs list. When the nsim_bpf_create_prog() performs
list_add_tail, it is possible that nsim_bpf_destroy_prog() is
simultaneously performs list_del. Concurrent operations on the list may
lead to list corruption and trigger a kernel crash as follows:
[ 417.290971] kernel BUG at lib/list_debug.c:62!
[ 417.290983] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[ 417.290992] CPU: 10 PID: 168 Comm: kworker/10:1 Kdump: loaded Not tainted 6.19.0-rc5 #1
[ 417.291003] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 417.291007] Workqueue: events bpf_prog_free_deferred
[ 417.291021] RIP: 0010:__list_del_entry_valid_or_report+0xa7/0xc0
[ 417.291034] Code: a8 ff 0f 0b 48 89 fe 48 89 ca 48 c7 c7 48 a1 eb ae e8 ed fb a8 ff 0f 0b 48 89 fe 48 89 c2 48 c7 c7 80 a1 eb ae e8 d9 fb a8 ff <0f> 0b 48 89 d1 48 c7 c7 d0 a1 eb ae 48 89 f2 48 89 c6 e8 c2 fb a8
[ 417.291040] RSP: 0018:ffffb16a40807df8 EFLAGS: 00010246
[ 417.291046] RAX: 000000000000006d RBX: ffff8e589866f500 RCX: 0000000000000000
[ 417.291051] RDX: 0000000000000000 RSI: ffff8e59f7b23180 RDI: ffff8e59f7b23180
[ 417.291055] RBP: ffffb16a412c9000 R08: 0000000000000000 R09: 0000000000000003
[ 417.291059] R10: ffffb16a40807c80 R11: ffffffffaf9edce8 R12: ffff8e594427ac20
[ 417.291063] R13: ffff8e59f7b44780 R14: ffff8e58800b7a05 R15: 0000000000000000
[ 417.291074] FS: 0000000000000000(0000) GS:ffff8e59f7b00000(0000) knlGS:0000000000000000
[ 417.291079] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 417.291083] CR2: 00007fc4083efe08 CR3: 00000001c3626006 CR4: 0000000000770ee0
[ 417.291088] PKRU: 55555554
[ 417.291091] Call Trace:
[ 417.291096] <TASK>
[ 417.291103] nsim_bpf_destroy_prog+0x31/0x80 [netdevsim]
[ 417.291154] __bpf_prog_offload_destroy+0x2a/0x80
[ 417.291163] bpf_prog_dev_bound_destroy+0x6f/0xb0
[ 417.291171] bpf_prog_free_deferred+0x18e/0x1a0
[ 417.291178] process_one_work+0x18a/0x3a0
[ 417.291188] worker_thread+0x27b/0x3a0
[ 417.291197] ? __pfx_worker_thread+0x10/0x10
[ 417.291207] kthread+0xe5/0x120
[ 417.291214] ? __pfx_kthread+0x10/0x10
[ 417.291221] ret_from_fork+0x31/0x50
[ 417.291230] ? __pfx_kthread+0x10/0x10
[ 417.291236] ret_from_fork_asm+0x1a/0x30
[ 417.291246] </TASK>
Add a mutex lock, to prevent simultaneous addition and deletion operations
on the list. |
| In the Linux kernel, the following vulnerability has been resolved:
dpll: Prevent duplicate registrations
Modify the internal registration helpers dpll_xa_ref_{dpll,pin}_add()
to reject duplicate registration attempts.
Previously, if a caller attempted to register the same pin multiple
times (with the same ops, priv, and cookie) on the same device, the core
silently increments the reference count and return success. This behavior
is incorrect because if the caller makes these duplicate registrations
then for the first one dpll_pin_registration is allocated and for others
the associated dpll_pin_ref.refcount is incremented. During the first
unregistration the associated dpll_pin_registration is freed and for
others WARN is fired.
Fix this by updating the logic to return `-EEXIST` if a matching
registration is found to enforce a strict "register once" policy. |
| In the Linux kernel, the following vulnerability has been resolved:
slab: fix kmalloc_nolock() context check for PREEMPT_RT
On PREEMPT_RT kernels, local_lock becomes a sleeping lock. The current
check in kmalloc_nolock() only verifies we're not in NMI or hard IRQ
context, but misses the case where preemption is disabled.
When a BPF program runs from a tracepoint with preemption disabled
(preempt_count > 0), kmalloc_nolock() proceeds to call
local_lock_irqsave() which attempts to acquire a sleeping lock,
triggering:
BUG: sleeping function called from invalid context
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 6128
preempt_count: 2, expected: 0
Fix this by checking !preemptible() on PREEMPT_RT, which directly
expresses the constraint that we cannot take a sleeping lock when
preemption is disabled. This encompasses the previous checks for NMI
and hard IRQ contexts while also catching cases where preemption is
disabled. |
| In the Linux kernel, the following vulnerability has been resolved:
libceph: reset sparse-read state in osd_fault()
When a fault occurs, the connection is abandoned, reestablished, and any
pending operations are retried. The OSD client tracks the progress of a
sparse-read reply using a separate state machine, largely independent of
the messenger's state.
If a connection is lost mid-payload or the sparse-read state machine
returns an error, the sparse-read state is not reset. The OSD client
will then interpret the beginning of a new reply as the continuation of
the old one. If this makes the sparse-read machinery enter a failure
state, it may never recover, producing loops like:
libceph: [0] got 0 extents
libceph: data len 142248331 != extent len 0
libceph: osd0 (1)...:6801 socket error on read
libceph: data len 142248331 != extent len 0
libceph: osd0 (1)...:6801 socket error on read
Therefore, reset the sparse-read state in osd_fault(), ensuring retries
start from a clean state. |
| In the Linux kernel, the following vulnerability has been resolved:
tracing: Add recursion protection in kernel stack trace recording
A bug was reported about an infinite recursion caused by tracing the rcu
events with the kernel stack trace trigger enabled. The stack trace code
called back into RCU which then called the stack trace again.
Expand the ftrace recursion protection to add a set of bits to protect
events from recursion. Each bit represents the context that the event is
in (normal, softirq, interrupt and NMI).
Have the stack trace code use the interrupt context to protect against
recursion.
Note, the bug showed an issue in both the RCU code as well as the tracing
stacktrace code. This only handles the tracing stack trace side of the
bug. The RCU fix will be handled separately. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf, test_run: Subtract size of xdp_frame from allowed metadata size
The xdp_frame structure takes up part of the XDP frame headroom,
limiting the size of the metadata. However, in bpf_test_run, we don't
take this into account, which makes it possible for userspace to supply
a metadata size that is too large (taking up the entire headroom).
If userspace supplies such a large metadata size in live packet mode,
the xdp_update_frame_from_buff() call in xdp_test_run_init_page() call
will fail, after which packet transmission proceeds with an
uninitialised frame structure, leading to the usual Bad Stuff.
The commit in the Fixes tag fixed a related bug where the second check
in xdp_update_frame_from_buff() could fail, but did not add any
additional constraints on the metadata size. Complete the fix by adding
an additional check on the metadata size. Reorder the checks slightly to
make the logic clearer and add a comment. |
| In the Linux kernel, the following vulnerability has been resolved:
flex_proportions: make fprop_new_period() hardirq safe
Bernd has reported a lockdep splat from flexible proportions code that is
essentially complaining about the following race:
<timer fires>
run_timer_softirq - we are in softirq context
call_timer_fn
writeout_period
fprop_new_period
write_seqcount_begin(&p->sequence);
<hardirq is raised>
...
blk_mq_end_request()
blk_update_request()
ext4_end_bio()
folio_end_writeback()
__wb_writeout_add()
__fprop_add_percpu_max()
if (unlikely(max_frac < FPROP_FRAC_BASE)) {
fprop_fraction_percpu()
seq = read_seqcount_begin(&p->sequence);
- sees odd sequence so loops indefinitely
Note that a deadlock like this is only possible if the bdi has configured
maximum fraction of writeout throughput which is very rare in general but
frequent for example for FUSE bdis. To fix this problem we have to make
sure write section of the sequence counter is irqsafe. |