| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
tcp: Fix potential UAF in reqsk_timer_handler().
When TCP socket migration fails at inet_ehash_insert() in
reqsk_timer_handler(), we jump to the no_ownership: label
and free the new reqsk immediately with __reqsk_free().
Thus, we must stop the new reqsk's timer before jumping to the
label, but the timer might be missed since the cited commit,
resulting in UAF.
As we are in the original reqsk's timer context, we can safely
call timer_delete_sync() for the new reqsk.
Let's pass false to __inet_csk_reqsk_queue_drop() to stop
the new reqsk's timer. |
| In the Linux kernel, the following vulnerability has been resolved:
io_uring/cancel: rearm local work wake up before sleep
io_uring_try_cancel_requests() sets ->cq_wait_nr to 1 so that the next
io_req_local_work_add() wakes the cancelling task. The add that takes the
count to zero is the only one that wakes, later ones see a count <= 0 and
return. io_uring_cancel_generic() however only becomes
TASK_INTERRUPTIBLE much later, so the one wake up can be spent on a
running task. That is fine as long as the entry of that add is still
queued, as the io_local_work_pending() check then skips the sleep. It is
not if the add was delayed after queueing its entry:
CPU0 (submitter in exec or exit) CPU1 (io_req_local_work_add)
mpscq_push(req A)
io_uring_try_cancel_requests()
io_run_local_work() // runs req A
io_uring_try_cancel_requests()
atomic_set(&ctx->cq_wait_nr, 1)
atomic_read(&ctx->cq_wait_nr) == 1
count taken, wake_up_state()
// task is running, no-op
prepare_to_wait(TASK_INTERRUPTIBLE)
io_local_work_pending() == false
schedule()
mpscq_push(req B)
cq_wait_nr <= 0, return
Only the sleeping task can run req B, so it is stuck in execve() until a
signal happens to wake it. An exiting task doesn't even get that.
Arm the count again once the task state is set and before the work list
is checked, for the rings whose local work this task is the one to run. |
| In the Linux kernel, the following vulnerability has been resolved:
io_uring/io-wq: don't hide a link from cancellations
A task that exits cancels its tracked requests and waits until they are
gone. io_uring_cancel_generic() looks everywhere a request can be, and
goes to sleep if it found nothing to cancel. It is woken up each time
one of the requests of the task is completed by task work or freed.
When io-wq is done with a request that has a link, there is a time in which
the next request of the link can't be found:
io_worker_handle_work()
io_assign_current_work(worker, NULL)
io_wq_free_work(work)
io_req_find_next() // takes the link off the request
io_free_req() // task work for the task
io_assign_current_work(worker, linked)
io_run_task_work()
cond_resched()
worker->cur_work = linked
It is not pending, it is not the current work of a worker, and it is not
yet on the list that it is about to be parked on. If the pass that the
exiting task makes because of io_free_req() falls into that time, it finds
nothing and the task goes to sleep. The worker then runs the link, which
IO_WQ_BIT_EXIT doesn't prevent for bounded work. If that parks the request
nothing is completed or freed, and nobody wakes up the task. If it is the
process that exits it can't be killed any more either.
NOP, IOSQE_ASYNC | IOSQE_IO_LINK
FUTEX_WAIT, FUTEX2_PRIVATE
exit of the thread, or of the process, up to 63us later
With four of these per round 5 to 8 of 10,000 rounds hang (4 CPUs, KVM):
io_uring_cancel_generic
do_exit
Commit f8b632e89a10 ("io_uring: tighten task exit cancellations") is about
the same gap, and makes the task look again for whatever happens before
io_free_req().
Free the request once the link is the current work of the worker, or
pending. Whoever is woken up by that can find the link, until it is parked
where cancellations look as well. To do so split io_wq_free_work() in two. |
| In the Linux kernel, the following vulnerability has been resolved:
dm cache: fix issue with background work locking
dm cache used a rw_semaphore for background_work_lock. Write locks on
rw_semaphores have strict owner semantics, but there was no guarantee
that the process that locked background_work_lock was the same process
that unlocked it. This can be easily seen using a kernel compiled with
CONFIG_DEBUG_RWSEMS. Given a dm cache device <cache>, run: 'dmsetup
suspend <cache> && dmsetup resume <cache>'. This will trigger a kernel
warning:
DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE))
triggered by cache_resume(). To fix this, switch from a rw_semaphore to
a spinlock and a wait queue. dm cache already has a wait queue and
associated counter, migration_wait and nr_allocated_migrations, that was
getting woken up when background work was getting completed, but wasn't
actually used by anything. This is replaced by the background_work queue
and counter. |
| In the Linux kernel, the following vulnerability has been resolved:
x86/hyperv: Avoid using per-cpu output page in hv_apicid_to_vp_index()
hv_apicid_to_vp_index() currently uses the per-cpu hypercall input
and output pages. This function is called when running in VTL2 and
when running in an SEV-SNP CoCo VM with no paravisor. In the former
case, the output page is allocated, but in the latter case it is
not, so the hypervisor stores the output VP index in memory that has
not been allocated by the guest.
Fix this by using the input page for both input and output. The
hypercall has very small input and output, so sharing the same
page for both is straightforward. An alternative fix is to
allocate the per-cpu output page when running in an SEV-SNP CoCo
guest, but this uses significantly more memory, particularly
with larger vCPUs counts. |
| In the Linux kernel, the following vulnerability has been resolved:
soc/tegra: pmc: Fix uninitialised clock rate
For legacy 32-bit Tegra devices, the warning in the
tegra_pmc_enter_suspend_mode() function is being triggered because the
early_pmc->rate variable is never configured and hence, always 0. This
issue started occurring after updating the PMC driver to create the PMC
context dynamically which causes the 'rate' to be set in the new dynamic
context, but missed updating the rate in the early PMC context.
Fix this by initialising the early_pmc->rate variable for 32-bit Tegra
devices when the rate for the PMC context is initialised.
[treding@nvidia.com: move assignment to existing #ifdef block] |
| In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Wait for SCX_OPSS_DISPATCHING before moving tasks off DSQs
A task can be found on a non-local DSQ while the CPU which dispatched it
is still running ops.dequeue() and hasn't cleared SCX_OPSS_DISPATCHING.
The DSQ consume and move paths don't wait for the dispatch to finish and
can operate on the task concurrently with the dispatcher.
Call scx_wait_dispatching() in scx_move_local_task_to_local_dsq(),
unlink_dsq_and_switch_rq_lock() and move_task_between_dsqs() before they
operate on the task. In scx_move_local_task_to_local_dsq(), wait before
scx_resolve_local_dsq() as it may update p->scx.flags. |
| An out-of-bounds read vulnerability was found in smb2_dump_detail in fs/smb/client/smb2ops.c in the Linux Kernel. This issue could allow a local attacker to crash the system or leak internal kernel information. |
| A vulnerability was reported in the Open vSwitch sub-component in the Linux Kernel. The flaw occurs when a recursive operation of code push recursively calls into the code block. The OVS module does not validate the stack depth, pushing too many frames and causing a stack overflow. As a result, this can lead to a crash or other related issues. |
| A null pointer dereference flaw was found in the hugetlbfs_fill_super function in the Linux kernel hugetlbfs (HugeTLB pages) functionality. This issue may allow a local user to crash the system or potentially escalate their privileges on the system. |
| A use-after-free flaw was found in the __ext4_remount in fs/ext4/super.c in ext4 in the Linux kernel. This flaw allows a local user to cause an information leak problem while freeing the old quota file names before a potential failure, leading to a use-after-free. |
| A denial of service vulnerability was found in tipc_crypto_key_revoke in net/tipc/crypto.c in the Linux kernel’s TIPC subsystem. This flaw allows guests with local user privileges to trigger a deadlock and potentially crash the system. |
| A denial of service vulnerability due to a deadlock was found in sctp_auto_asconf_init in net/sctp/socket.c in the Linux kernel’s SCTP subsystem. This flaw allows guests with local user privileges to trigger a deadlock and potentially crash the system. |
| A flaw was found in the Netfilter subsystem in the Linux kernel. The issue is in the nft_byteorder_eval() function, where the code iterates through a loop and writes to the `dst` array. On each iteration, 8 bytes are written, but `dst` is an array of u32, so each element only has space for 4 bytes. That means every iteration overwrites part of the previous element corrupting this array of u32. This flaw allows a local user to cause a denial of service or potentially break NetFilter functionality. |
| A use-after-free flaw was found in the Linux Kernel. When a disk is removed, bdi_unregister is called to stop further write-back and waits for associated delayed work to complete. However, wb_inode_writeback_end() may schedule bandwidth estimation work after this has completed, which can result in the timer attempting to access the recently freed bdi_writeback. |
| An out-of-bounds memory read flaw was found in receive_encrypted_standard in fs/smb/client/smb2ops.c in the SMB Client sub-component in the Linux Kernel. This issue occurs due to integer underflow on the memcpy length, leading to a denial of service. |
| A flaw was found in the blkgs destruction path in block/blk-cgroup.c in the Linux kernel, leading to a cgroup blkio memory leakage problem. When a cgroup is being destroyed, cgroup_rstat_flush() is only called at css_release_work_fn(), which is called when the blkcg reference count reaches 0. This circular dependency will prevent blkcg and some blkgs from being freed after they are made offline. This issue may allow an attacker with a local access to cause system instability, such as an out of memory error. |
| A memory leak problem was found in ctnetlink_create_conntrack in net/netfilter/nf_conntrack_netlink.c in the Linux Kernel. This issue may allow a local attacker with CAP_NET_ADMIN privileges to cause a denial of service (DoS) attack due to a refcount overflow. |
| A Null pointer dereference problem was found in ida_free in lib/idr.c in the Linux Kernel. This issue may allow an attacker using this library to cause a denial of service problem due to a missing check at a function return. |
| A null pointer dereference vulnerability was found in nft_dynset_init() in net/netfilter/nft_dynset.c in nf_tables in the Linux kernel. This issue may allow a local attacker with CAP_NET_ADMIN user privilege to trigger a denial of service. |
