In the Linux kernel, the following vulnerability has been resolved: mm/slab: do not access...

CVE-2026-43285 → View on GitHub ↗ View on CVE.org ↗ View on NVD ↗

Description

In the Linux kernel, the following vulnerability has been resolved:

mm/slab: do not access current->mems_allowed_seq if !allow_spin

Lockdep complains when get_from_any_partial() is called in an NMI
context, because current->mems_allowed_seq is seqcount_spinlock_t and
not NMI-safe:

================================
WARNING: inconsistent lock state
6.19.0-rc5-kfree-rcu+ #315 Tainted: G N

inconsistent {INITIAL USE} -> {IN-NMI} usage.
kunit_try_catch/9989 [HC1[1]:SC0[0]:HE0:SE1] takes:
ffff889085799820 (&_s->seqcount#3){.-.-}-{0:0}, at: slab_alloc+0x58f/0xc00
{INITIAL USE} state was registered at:
lock_acquire+0x185/0x320
kernel_init_freeable+0x391/0x1150
kernel_init+0x1f/0x220
ret_from_fork+0x736/0x8f0
ret_from_fork_asm+0x1a/0x30
irq event stamp: 56
hardirqs last enabled at (55): [<ffffffff850a68d7>] _raw_spin_unlock_irq+0x27/0x70
hardirqs last disabled at (56): [<ffffffff850858ca>] __schedule+0x2a8a/0x6630
softirqs last enabled at (0): [<ffffffff81536711>] copy_process+0x1dc1/0x6a10
softirqs last disabled at (0): [<0000000000000000>] 0x0

other info that might help us debug this:
Possible unsafe locking scenario:

     CPU0
     ----
lock(&amp;____s-&gt;seqcount#3);
&lt;Interrupt&gt;
  lock(&amp;____s-&gt;seqcount#3);

*** DEADLOCK ***

According to Documentation/locking/seqlock.rst, seqcount_t is not
NMI-safe and seqcount_latch_t should be used when read path can interrupt
the write-side critical section. In this case, do not access
current->mems_allowed_seq and avoid retry.

Basic information

Type
unreviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
—
Source code
Not specified
Published (advisory)
2026-05-08 15:31:22 UTC
Updated
2026-05-14 21:31:40 UTC
NVD published
2026-05-08 14:16:35 UTC

EPSS Score

Score Percentile
0.01% 2.18%

CVSS Scores

Base score Version Severity Vector
5.5 3.1 —
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.

Identifiers

Type Value
GHSA GHSA-v2vh-p96v-7cc2 ↗
CVE CVE-2026-43285 ↗

References

cvelogic Threat Intelligence