Linux: >> Linux Kernel >> 6.1.133 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
hrtimers: Force migrate away hrtimers queued after CPUHP_AP_HRTIMERS_DYING
hrtimers are migrated away from the dying CPU to any online target at
the CPUHP_AP_HRTIMERS_DYING stage in order not to delay bandwidth timers
handling tasks involved in the CPU hotplug forward progress.
However wakeups can still be performed by the outgoing CPU after
CPUHP_AP_HRTIMERS_DYING. Those can result again in bandwidth timers being
armed. Depending on several considerations (crystal ball power management
based election, earliest timer already enqueued, timer migration enabled or
not), the target may eventually be the current CPU even if offline. If that
happens, the timer is eventually ignored.
The most notable example is RCU which had to deal with each and every of
those wake-ups by deferring them to an online CPU, along with related
workarounds:
_ e787644caf76 (rcu: Defer RCU kthreads wakeup when CPU is dying)
_ 9139f93209d1 (rcu/nocb: Fix RT throttling hrtimer armed from offline CPU)
_ f7345ccc62a4 (rcu/nocb: Fix rcuog wake-up from offline softirq)
The problem isn't confined to RCU though as the stop machine kthread
(which runs CPUHP_AP_HRTIMERS_DYING) reports its completion at the end
of its work through cpu_stop_signal_done() and performs a wake up that
eventually arms the deadline server timer:
WARNING: CPU: 94 PID: 588 at kernel/time/hrtimer.c:1086 hrtimer_start_range_ns+0x289/0x2d0
CPU: 94 UID: 0 PID: 588 Comm: migration/94 Not tainted
Stopper: multi_cpu_stop+0x0/0x120 <- stop_machine_cpuslocked+0x66/0xc0
RIP: 0010:hrtimer_start_range_ns+0x289/0x2d0
Call Trace:
<TASK>
start_dl_timer
enqueue_dl_entity
dl_server_start
enqueue_task_fair
enqueue_task
ttwu_do_activate
try_to_wake_up
complete
cpu_stopper_thread
Instead of providing yet another bandaid to work around the situation, fix
it in the hrtimers infrastructure instead: always migrate away a timer to
an online target whenever it is enqueued from an offline CPU.
This will also allow to revert all the above RCU disgraceful hacks.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-27
In the Linux kernel, the following vulnerability has been resolved:
net: ravb: Fix missing rtnl lock in suspend/resume path
Fix the suspend/resume path by ensuring the rtnl lock is held where
required. Calls to ravb_open, ravb_close and wol operations must be
performed under the rtnl lock to prevent conflicts with ongoing ndo
operations.
Without this fix, the following warning is triggered:
[ 39.032969] =============================
[ 39.032983] WARNING: suspicious RCU usage
[ 39.033019] -----------------------------
[ 39.033033] drivers/net/phy/phy_device.c:2004 suspicious
rcu_dereference_protected() usage!
...
[ 39.033597] stack backtrace:
[ 39.033613] CPU: 0 UID: 0 PID: 174 Comm: python3 Not tainted
6.13.0-rc7-next-20250116-arm64-renesas-00002-g35245dfdc62c #7
[ 39.033623] Hardware name: Renesas SMARC EVK version 2 based on
r9a08g045s33 (DT)
[ 39.033628] Call trace:
[ 39.033633] show_stack+0x14/0x1c (C)
[ 39.033652] dump_stack_lvl+0xb4/0xc4
[ 39.033664] dump_stack+0x14/0x1c
[ 39.033671] lockdep_rcu_suspicious+0x16c/0x22c
[ 39.033682] phy_detach+0x160/0x190
[ 39.033694] phy_disconnect+0x40/0x54
[ 39.033703] ravb_close+0x6c/0x1cc
[ 39.033714] ravb_suspend+0x48/0x120
[ 39.033721] dpm_run_callback+0x4c/0x14c
[ 39.033731] device_suspend+0x11c/0x4dc
[ 39.033740] dpm_suspend+0xdc/0x214
[ 39.033748] dpm_suspend_start+0x48/0x60
[ 39.033758] suspend_devices_and_enter+0x124/0x574
[ 39.033769] pm_suspend+0x1ac/0x274
[ 39.033778] state_store+0x88/0x124
[ 39.033788] kobj_attr_store+0x14/0x24
[ 39.033798] sysfs_kf_write+0x48/0x6c
[ 39.033808] kernfs_fop_write_iter+0x118/0x1a8
[ 39.033817] vfs_write+0x27c/0x378
[ 39.033825] ksys_write+0x64/0xf4
[ 39.033833] __arm64_sys_write+0x18/0x20
[ 39.033841] invoke_syscall+0x44/0x104
[ 39.033852] el0_svc_common.constprop.0+0xb4/0xd4
[ 39.033862] do_el0_svc+0x18/0x20
[ 39.033870] el0_svc+0x3c/0xf0
[ 39.033880] el0t_64_sync_handler+0xc0/0xc4
[ 39.033888] el0t_64_sync+0x154/0x158
[ 39.041274] ravb 11c30000.ethernet eth0: Link is Down
CVSS Score
5.5
EPSS Score
0.001
Published
2025-02-27
In the Linux kernel, the following vulnerability has been resolved:
workqueue: Put the pwq after detaching the rescuer from the pool
The commit 68f83057b913("workqueue: Reap workers via kthread_stop() and
remove detach_completion") adds code to reap the normal workers but
mistakenly does not handle the rescuer and also removes the code waiting
for the rescuer in put_unbound_pool(), which caused a use-after-free bug
reported by Cheung Wall.
To avoid the use-after-free bug, the pool’s reference must be held until
the detachment is complete. Therefore, move the code that puts the pwq
after detaching the rescuer from the pool.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-02-27
In the Linux kernel, the following vulnerability has been resolved:
net: ipv6: fix dst ref loops in rpl, seg6 and ioam6 lwtunnels
Some lwtunnels have a dst cache for post-transformation dst.
If the packet destination did not change we may end up recording
a reference to the lwtunnel in its own cache, and the lwtunnel
state will never be freed.
Discovered by the ioam6.sh test, kmemleak was recently fixed
to catch per-cpu memory leaks. I'm not sure if rpl and seg6
can actually hit this, but in principle I don't see why not.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-02-27
In the Linux kernel, the following vulnerability has been resolved:
ipv6: mcast: extend RCU protection in igmp6_send()
igmp6_send() can be called without RTNL or RCU being held.
Extend RCU protection so that we can safely fetch the net pointer
and avoid a potential UAF.
Note that we no longer can use sock_alloc_send_skb() because
ipv6.igmp_sk uses GFP_KERNEL allocations which can sleep.
Instead use alloc_skb() and charge the net->ipv6.igmp_sk
socket under RCU protection.
CVSS Score
7.8
EPSS Score
0.006
Published
2025-02-27
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: HWS, change error flow on matcher disconnect
Currently, when firmware failure occurs during matcher disconnect flow,
the error flow of the function reconnects the matcher back and returns
an error, which continues running the calling function and eventually
frees the matcher that is being disconnected.
This leads to a case where we have a freed matcher on the matchers list,
which in turn leads to use-after-free and eventual crash.
This patch fixes that by not trying to reconnect the matcher back when
some FW command fails during disconnect.
Note that we're dealing here with FW error. We can't overcome this
problem. This might lead to bad steering state (e.g. wrong connection
between matchers), and will also lead to resource leakage, as it is
the case with any other error handling during resource destruction.
However, the goal here is to allow the driver to continue and not crash
the machine with use-after-free error.
CVSS Score
7.8
EPSS Score
0.001
Published
2025-02-27
In the Linux kernel, the following vulnerability has been resolved:
scsi: ufs: core: Fix use-after free in init error and remove paths
devm_blk_crypto_profile_init() registers a cleanup handler to run when
the associated (platform-) device is being released. For UFS, the
crypto private data and pointers are stored as part of the ufs_hba's
data structure 'struct ufs_hba::crypto_profile'. This structure is
allocated as part of the underlying ufshcd and therefore Scsi_host
allocation.
During driver release or during error handling in ufshcd_pltfrm_init(),
this structure is released as part of ufshcd_dealloc_host() before the
(platform-) device associated with the crypto call above is released.
Once this device is released, the crypto cleanup code will run, using
the just-released 'struct ufs_hba::crypto_profile'. This causes a
use-after-free situation:
Call trace:
kfree+0x60/0x2d8 (P)
kvfree+0x44/0x60
blk_crypto_profile_destroy_callback+0x28/0x70
devm_action_release+0x1c/0x30
release_nodes+0x6c/0x108
devres_release_all+0x98/0x100
device_unbind_cleanup+0x20/0x70
really_probe+0x218/0x2d0
In other words, the initialisation code flow is:
platform-device probe
ufshcd_pltfrm_init()
ufshcd_alloc_host()
scsi_host_alloc()
allocation of struct ufs_hba
creation of scsi-host devices
devm_blk_crypto_profile_init()
devm registration of cleanup handler using platform-device
and during error handling of ufshcd_pltfrm_init() or during driver
removal:
ufshcd_dealloc_host()
scsi_host_put()
put_device(scsi-host)
release of struct ufs_hba
put_device(platform-device)
crypto cleanup handler
To fix this use-after free, change ufshcd_alloc_host() to register a
devres action to automatically cleanup the underlying SCSI device on
ufshcd destruction, without requiring explicit calls to
ufshcd_dealloc_host(). This way:
* the crypto profile and all other ufs_hba-owned resources are
destroyed before SCSI (as they've been registered after)
* a memleak is plugged in tc-dwc-g210-pci.c remove() as a
side-effect
* EXPORT_SYMBOL_GPL(ufshcd_dealloc_host) can be removed fully as
it's not needed anymore
* no future drivers using ufshcd_alloc_host() could ever forget
adding the cleanup
CVSS Score
7.8
EPSS Score
0.0
Published
2025-02-27
In the Linux kernel, the following vulnerability has been resolved:
RDMA/mlx5: Fix a race for an ODP MR which leads to CQE with error
This patch addresses a race condition for an ODP MR that can result in a
CQE with an error on the UMR QP.
During the __mlx5_ib_dereg_mr() flow, the following sequence of calls
occurs:
mlx5_revoke_mr()
mlx5r_umr_revoke_mr()
mlx5r_umr_post_send_wait()
At this point, the lkey is freed from the hardware's perspective.
However, concurrently, mlx5_ib_invalidate_range() might be triggered by
another task attempting to invalidate a range for the same freed lkey.
This task will:
- Acquire the umem_odp->umem_mutex lock.
- Call mlx5r_umr_update_xlt() on the UMR QP.
- Since the lkey has already been freed, this can lead to a CQE error,
causing the UMR QP to enter an error state [1].
To resolve this race condition, the umem_odp->umem_mutex lock is now also
acquired as part of the mlx5_revoke_mr() scope. Upon successful revoke,
we set umem_odp->private which points to that MR to NULL, preventing any
further invalidation attempts on its lkey.
[1] From dmesg:
infiniband rocep8s0f0: dump_cqe:277:(pid 0): WC error: 6, Message: memory bind operation error
cqe_dump: 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
cqe_dump: 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
cqe_dump: 00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
cqe_dump: 00000030: 00 00 00 00 08 00 78 06 25 00 11 b9 00 0e dd d2
WARNING: CPU: 15 PID: 1506 at drivers/infiniband/hw/mlx5/umr.c:394 mlx5r_umr_post_send_wait+0x15a/0x2b0 [mlx5_ib]
Modules linked in: ip6table_mangle ip6table_natip6table_filter ip6_tables iptable_mangle xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink xt_addrtype iptable_nat nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcgss oid_registry overlay rpcrdma rdma_ucm ib_iser libiscsi scsi_transport_iscsi rdma_cm iw_cm ib_umad ib_ipoib ib_cm mlx5_ib ib_uverbs ib_core fuse mlx5_core
CPU: 15 UID: 0 PID: 1506 Comm: ibv_rc_pingpong Not tainted 6.12.0-rc7+ #1626
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:mlx5r_umr_post_send_wait+0x15a/0x2b0 [mlx5_ib]
[..]
Call Trace:
<TASK>
mlx5r_umr_update_xlt+0x23c/0x3e0 [mlx5_ib]
mlx5_ib_invalidate_range+0x2e1/0x330 [mlx5_ib]
__mmu_notifier_invalidate_range_start+0x1e1/0x240
zap_page_range_single+0xf1/0x1a0
madvise_vma_behavior+0x677/0x6e0
do_madvise+0x1a2/0x4b0
__x64_sys_madvise+0x25/0x30
do_syscall_64+0x6b/0x140
entry_SYSCALL_64_after_hwframe+0x76/0x7e
CVSS Score
4.7
EPSS Score
0.0
Published
2025-02-27
In the Linux kernel, the following vulnerability has been resolved:
ASoC: SOF: Intel: hda-dai: Ensure DAI widget is valid during params
Each cpu DAI should associate with a widget. However, the topology might
not create the right number of DAI widgets for aggregated amps. And it
will cause NULL pointer deference.
Check that the DAI widget associated with the CPU DAI is valid to prevent
NULL pointer deference due to missing DAI widgets in topologies with
aggregated amps.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-27
In the Linux kernel, the following vulnerability has been resolved:
media: uvcvideo: Remove dangling pointers
When an async control is written, we copy a pointer to the file handle
that started the operation. That pointer will be used when the device is
done. Which could be anytime in the future.
If the user closes that file descriptor, its structure will be freed,
and there will be one dangling pointer per pending async control, that
the driver will try to use.
Clean all the dangling pointers during release().
To avoid adding a performance penalty in the most common case (no async
operation), a counter has been introduced with some logic to make sure
that it is properly handled.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-02-27