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 71E81478875 for ; Wed, 13 May 2026 15:09:16 +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=1778684956; cv=none; b=WcxbL6JiToWlPcyHS1fKld2F5ic94hV07dWbj7NvmzTTQeaRnxjGJYdG/mSYNw+zepC/2cptFBKkAfFkZPHWETcF/i1BIitL/nk0ld90mHIfHcVHjaNM9Ij7cx9LQA8tZkYoZimAkltzgC4ks4T3ZazLVJ1sZY3YhBccIhUmuJg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778684956; c=relaxed/simple; bh=B/yK/wSy67B7jrf+YVoFyX6kv2gaXVXANOb8V+m+5vE=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=OY2T42fmxWwVLWOFamxwOsz9uj7cP7QiaZegyJ1By6HogKFkOgK2iJ8I6Z76M6eTZGpWgA1ijIyNiY0XFS6achUWpPi23ckEA8I6A2cBPNp1pVR8IEVid0nif28VUPZ0KlI78MBPta3XGtVMBRtUgiUhQgvtYZ2HS1ww4llcsaU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=d/rzDKH8; 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="d/rzDKH8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BF0CCC19425; Wed, 13 May 2026 15:09:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1778684956; bh=B/yK/wSy67B7jrf+YVoFyX6kv2gaXVXANOb8V+m+5vE=; h=From:To:Cc:Subject:Date:Reply-To:From; b=d/rzDKH8NflmFOzEYX5kDVX/SuZbClElYZ/8x3lvvEZXjhDniIoKK67CkfyGK84V9 FZaTr9k/39n/FUL05duGwV0mc6ObtREVFBDizg0QM89UF/Bq4cXd5TK4LvxHdJkAGw omfxZf3zKGyXOmJV76mocPnmLkDPU0ZmrN3z2eGE= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-43482: sched_ext: Disable preemption between scx_claim_exit() and kicking helper work Date: Wed, 13 May 2026 17:08:50 +0200 Message-ID: <2026051348-CVE-2026-43482-8a3e@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=2969; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=456AK7IrD0e28CNl/wWPHhdXfIM4asHuHZxUD754FgA=; b=owGbwMvMwCRo6H6F97bub03G02pJDFksUxjdLjxov3j76cnGALOfK+SPbT/r7Tl7XfmuI21vX 0W3hZ772hHLwiDIxCArpsjyZRvP0f0VhxS9DG1Pw8xhZQIZwsDFKQATSVzFMJv9aKrn0pAgQU5O vt+9idmPZmjPk2eYzTo37u/m7cpic9M861a26p7au3b6IgA= 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: sched_ext: Disable preemption between scx_claim_exit() and kicking helper work scx_claim_exit() atomically sets exit_kind, which prevents scx_error() from triggering further error handling. After claiming exit, the caller must kick the helper kthread work which initiates bypass mode and teardown. If the calling task gets preempted between claiming exit and kicking the helper work, and the BPF scheduler fails to schedule it back (since error handling is now disabled), the helper work is never queued, bypass mode never activates, tasks stop being dispatched, and the system wedges. Disable preemption across scx_claim_exit() and the subsequent work kicking in all callers - scx_disable() and scx_vexit(). Add lockdep_assert_preemption_disabled() to scx_claim_exit() to enforce the requirement. The Linux kernel CVE team has assigned CVE-2026-43482 to this issue. Affected and fixed versions =========================== Issue introduced in 6.12 with commit f0e1a0643a59bf1f922fa209cec86a170b784f3f and fixed in 6.12.78 with commit 41423912f7ac7494ccd6eef411227b4efce740e0 Issue introduced in 6.12 with commit f0e1a0643a59bf1f922fa209cec86a170b784f3f and fixed in 6.18.20 with commit 522acaae34aa7e05859260056b39c7c030592a0c Issue introduced in 6.12 with commit f0e1a0643a59bf1f922fa209cec86a170b784f3f and fixed in 6.19.9 with commit 5131dbec2c10961b34f844bc30b400c3fa0bcc72 Issue introduced in 6.12 with commit f0e1a0643a59bf1f922fa209cec86a170b784f3f and fixed in 7.0 with commit 83236b2e43dba00bee5b82eb5758816b1a674f6a 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-2026-43482 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: kernel/sched/ext.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/41423912f7ac7494ccd6eef411227b4efce740e0 https://git.kernel.org/stable/c/522acaae34aa7e05859260056b39c7c030592a0c https://git.kernel.org/stable/c/5131dbec2c10961b34f844bc30b400c3fa0bcc72 https://git.kernel.org/stable/c/83236b2e43dba00bee5b82eb5758816b1a674f6a