From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 AA27458E2A4 for ; Fri, 11 Sep 2026 20:03:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789157024; cv=none; b=M2pG18Aryaysw0RC4UUwHcIBtrAI+92nkXUeVB0KtXc90dxKBZphqqA3ag3K9wfL/0W85pIbNllp+beMXz+Z6DJGIncpfsnPFzwP/diw1+9dWuZ/UOYVoLoit0CUdS4lIDgTA3+ygYLqy9Vn6XLfGQfYB/2FCwr5vILYv7CpU6o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789157024; c=relaxed/simple; bh=tfAli08ibvblHy0I+5//eAo2yyYR0DzuaguSsndG5NU=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=rsaXSZEtM0dHWAAbb6R6JnkbRnsdkXh28q/pAb6mnXFLmW6PPVhEgkWO6xjW9DeqScm9fbMeszYWPYHHUyRd3Zu6GJLoTbsQfqRIaKvL1zfAQA2Q9FUsrldcXQaBRz5f9k2fbAfy3dfmH6vbQOuZr9xUGO9vcG4GfZZOBf+3jlo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=QLhIeC5d; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="QLhIeC5d" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 57BB71F00899; Fri, 11 Sep 2026 20:03:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789157015; bh=ori9IrO+IerlwB9f/dACl6Yw48rkrKrMN0Z0o4I54/Y=; h=From:To:Cc:Subject:Date:Reply-To; b=QLhIeC5d8HyHZB3VhcwjGfIN8val9B37rU0C3Hk2j/Tm6TMSUCBpbet+CAl0XUqsU w2ZoGN8xVc0n2bYBO2eTYWZiuZlpiCNAiOFA0Xwzs0ujpQJ1rQ6V/0uVRV6FrvvfLs 495hVFf+aDzXc/fnW/jgR5kAcc9Xy5Hib+yMpzuQ= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89709: lockd, nfsd: RCU-protect nlmsvc_ops dispatch Date: Fri, 11 Sep 2026 21:46:38 +0200 Message-ID: <2026091157-CVE-2026-89709-1438@gregkh> X-Mailer: git-send-email 2.55.0 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=2566; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=g+Rw7RiSniWy2rjcpcmjRfSPrqM4Xy23I3FuM8ml/E0=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLIlv/nIrc9/bj9If5J6Zu490appxWnxCxZHdkouT8s PNXfs1d2RHLwiDIxCArpsjyZRvP0f0VhxS9DG1Pw8xhZQIZwsDFKQATkXjDsGD7gtzt/hvmvuBf Kfytfv+q9olpgqwM812fnyi9ZPBjQnflitI9K9isvOyvBQIA 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: lockd, nfsd: RCU-protect nlmsvc_ops dispatch nlmsvc_ops is published by nfsd_lockd_init() and cleared by nfsd_lockd_shutdown() with plain stores, while lockd dereferences it unguarded from dispatch sites in fs/lockd/svcsubs.c. The pointer targets nfsd's .rodata and the fopen/fclose callbacks live in nfsd's .text, so a stale load after rmmod nfsd results in either a NULL deref or a module-text use-after-free. Declare nlmsvc_ops as __rcu, publish via rcu_assign_pointer(), clear via RCU_INIT_POINTER() + synchronize_rcu(). Add a struct module *owner field to nlmsvc_binding and pin the module across indirect calls with try_module_get/module_put. When the binding is torn down, fall back to fput() to avoid leaking struct file references. The Linux kernel CVE team has assigned CVE-2026-89709 to this issue. Affected and fixed versions =========================== Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.2.4 with commit 3c461a1820088fb5889d73a6522369bde45527a9 Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.3-rc1 with commit 641e5e20852359b8c31149be4598884e30652f60 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-2026-89709 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: fs/lockd/svc.c fs/lockd/svc4proc.c fs/lockd/svcproc.c fs/lockd/svcsubs.c fs/nfsd/lockd.c include/linux/lockd/bind.h 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/3c461a1820088fb5889d73a6522369bde45527a9 https://git.kernel.org/stable/c/641e5e20852359b8c31149be4598884e30652f60