Linux: >> Linux Kernel >> 2.6.21 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
ALSA: ac97: fix possible memory leak in snd_ac97_dev_register()
If device_register() fails in snd_ac97_dev_register(), it should
call put_device() to give up reference, or the name allocated in
dev_set_name() is leaked.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
ALSA: aoa: i2sbus: fix possible memory leak in i2sbus_add_dev()
dev_set_name() in soundbus_add_one() allocates memory for name, it need be
freed when of_device_register() fails, call soundbus_dev_put() to give up
the reference that hold in device_initialize(), so that it can be freed in
kobject_cleanup() when the refcount hit to 0. And other resources are also
freed in i2sbus_release_dev(), so it can return 0 directly.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
scsi: libsas: Fix use-after-free bug in smp_execute_task_sg()
When executing SMP task failed, the smp_execute_task_sg() calls del_timer()
to delete "slow_task->timer". However, if the timer handler
sas_task_internal_timedout() is running, the del_timer() in
smp_execute_task_sg() will not stop it and a UAF will happen. The process
is shown below:
(thread 1) | (thread 2)
smp_execute_task_sg() | sas_task_internal_timedout()
... |
del_timer() |
... | ...
sas_free_task(task) |
kfree(task->slow_task) //FREE|
| task->slow_task->... //USE
Fix by calling del_timer_sync() in smp_execute_task_sg(), which makes sure
the timer handler have finished before the "task->slow_task" is
deallocated.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: Fix UBSAN shift-out-of-bounds warning
If get_num_sdma_queues or get_num_xgmi_sdma_queues is 0, we end up
doing a shift operation where the number of bits shifted equals
number of bits in the operand. This behaviour is undefined.
Set num_sdma_queues or num_xgmi_sdma_queues to ULLONG_MAX, if the
count is >= number of bits in the operand.
Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1472
CVSS Score
7.1
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
net: phylink: add lock for serializing concurrent pl->phydev writes with resolver
Currently phylink_resolve() protects itself against concurrent
phylink_bringup_phy() or phylink_disconnect_phy() calls which modify
pl->phydev by relying on pl->state_mutex.
The problem is that in phylink_resolve(), pl->state_mutex is in a lock
inversion state with pl->phydev->lock. So pl->phydev->lock needs to be
acquired prior to pl->state_mutex. But that requires dereferencing
pl->phydev in the first place, and without pl->state_mutex, that is
racy.
Hence the reason for the extra lock. Currently it is redundant, but it
will serve a functional purpose once mutex_lock(&phy->lock) will be
moved outside of the mutex_lock(&pl->state_mutex) section.
Another alternative considered would have been to let phylink_resolve()
acquire the rtnl_mutex, which is also held when phylink_bringup_phy()
and phylink_disconnect_phy() are called. But since phylink_disconnect_phy()
runs under rtnl_lock(), it would deadlock with phylink_resolve() when
calling flush_work(&pl->resolve). Additionally, it would have been
undesirable because it would have unnecessarily blocked many other call
paths as well in the entire kernel, so the smaller-scoped lock was
preferred.
CVSS Score
7.0
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
ppp: fix memory leak in pad_compress_skb
If alloc_skb() fails in pad_compress_skb(), it returns NULL without
releasing the old skb. The caller does:
skb = pad_compress_skb(ppp, skb);
if (!skb)
goto drop;
drop:
kfree_skb(skb);
When pad_compress_skb() returns NULL, the reference to the old skb is
lost and kfree_skb(skb) ends up doing nothing, leading to a memory leak.
Align pad_compress_skb() semantics with realloc(): only free the old
skb if allocation and compression succeed. At the call site, use the
new_skb variable so the original skb is not lost when pad_compress_skb()
fails.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-19
In the Linux kernel, the following vulnerability has been resolved:
ax25: properly unshare skbs in ax25_kiss_rcv()
Bernard Pidoux reported a regression apparently caused by commit
c353e8983e0d ("net: introduce per netns packet chains").
skb->dev becomes NULL and we crash in __netif_receive_skb_core().
Before above commit, different kind of bugs or corruptions could happen
without a major crash.
But the root cause is that ax25_kiss_rcv() can queue/mangle input skb
without checking if this skb is shared or not.
Many thanks to Bernard Pidoux for his help, diagnosis and tests.
We had a similar issue years ago fixed with commit 7aaed57c5c28
("phonet: properly unshare skbs in phonet_rcv()").
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-19
In the Linux kernel, the following vulnerability has been resolved:
mfd: arizona: Use pm_runtime_resume_and_get() to prevent refcnt leak
In arizona_clk32k_enable(), we should use pm_runtime_resume_and_get()
as pm_runtime_get_sync() will increase the refcnt even when it
returns an error.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-18
In the Linux kernel, the following vulnerability has been resolved:
firewire: net: fix use after free in fwnet_finish_incoming_packet()
The netif_rx() function frees the skb so we can't dereference it to
save the skb->len.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-18
In the Linux kernel, the following vulnerability has been resolved:
media: uvcvideo: Handle cameras with invalid descriptors
If the source entity does not contain any pads, do not create a link.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-18