From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 48615330D4C for ; Fri, 8 May 2026 13:15:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778246100; cv=none; b=VBPDoEuwHB0dLx3ClUy0RZVUI2yTcsEGbHd6ZUfbWpKkx2NSFXAdhSCp5+43ukHL8hizQHu3/IoVOVnj1t1npKXaA/YHRfY6Csjr58krLq3rs2a2w8+TAhXamR+8AhDENglHXbHeyhv1xWijQ23oERY7XTTnFru6/V9f/1AjVzQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778246100; c=relaxed/simple; bh=u6JllDBV1fqEVvEbr6ywiog8qp61lO7mUZu01N04IyM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=eGnkiaODrn4hObgqdtGexVEiZwDf9QkjeewbybLIjUO4uIelaBnqYwwWEUt5UCWry7Sin89fnaaEoBORzS9HxUgnYmU8OjXuESWSWsQZf9MlJrE2qX7SSheyBlirkQKKwp56runZJDmHCGsfi6k+Ax8nIxeMplpBZHYGxRKgqRY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=hNjS/on9; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="hNjS/on9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 980F8C2BCB0; Fri, 8 May 2026 13:14:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1778246099; bh=u6JllDBV1fqEVvEbr6ywiog8qp61lO7mUZu01N04IyM=; h=From:To:Cc:Subject:Date:Reply-To:From; b=hNjS/on9w2m3PV76MC4WdWw21vaxWyUlRUAFHsDXNSWWzhmkF4ir9/9htK506yU+o o43WE8flwZo8zLhFY+A3JixySMUWb4UGo4JD+FKvyCM6AdggOxayu1bcsNx8sM2rZe 6rxajw4nrj3vDpoJUu+ffRPINYLL0tXnhPyfn8rI= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-43285: mm/slab: do not access current->mems_allowed_seq if !allow_spin Date: Fri, 8 May 2026 15:11:50 +0200 Message-ID: <2026050850-CVE-2026-43285-4680@gregkh> X-Mailer: git-send-email 2.54.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3498; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=A+qP8OsS11ExuTaLXn0DnFi7+KjsrKnsasKt2LB9aZM=; b=owGbwMvMwCRo6H6F97bub03G02pJDJl/H4onHZijkGGok/jTLXrrugdz159na27bKmmzavfqz F6dQwJxHbEsDIJMDLJiiixftvEc3V9xSNHL0PY0zBxWJpAhDFycAjCRpjqGuZJBeZ+5Jkx0NXtg 8fVursw06/JbmQwL5i9557HcQvCK/nrhAgfFBQ171gV9AgA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman 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): [] _raw_spin_unlock_irq+0x27/0x70 hardirqs last disabled at (56): [] __schedule+0x2a8a/0x6630 softirqs last enabled at (0): [] 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(&____s->seqcount#3); lock(&____s->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. The Linux kernel CVE team has assigned CVE-2026-43285 to this issue. Affected and fixed versions =========================== Issue introduced in 6.18 with commit af92793e52c3a99b828ed4bdd277fd3e11c18d08 and fixed in 6.18.16 with commit 353dd9934447b9193643ae1afd938607a74d4915 Issue introduced in 6.18 with commit af92793e52c3a99b828ed4bdd277fd3e11c18d08 and fixed in 6.19.6 with commit efd767ddcef0669bbd33c6a823ea0a88f06d4b29 Issue introduced in 6.18 with commit af92793e52c3a99b828ed4bdd277fd3e11c18d08 and fixed in 7.0 with commit 144080a5823b2dbd635acb6decf7ab23182664f3 Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-43285 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: mm/slub.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/353dd9934447b9193643ae1afd938607a74d4915 https://git.kernel.org/stable/c/efd767ddcef0669bbd33c6a823ea0a88f06d4b29 https://git.kernel.org/stable/c/144080a5823b2dbd635acb6decf7ab23182664f3