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 67FCB585979 for ; Fri, 11 Sep 2026 20:02:14 +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=1789156939; cv=none; b=LlveaqUcMyQiwHvykcRIkvU1fmjm6rqENKccKB25a6VVaqkcbxNEH/15G5Fba0uDrNIqEIhTOT82ekYXZ4nJwXSk1zwKDLgyM4LwaQ+pqI8n1SHRGJXJghJo6L7wICSDSiYyq3wBuMnZchxq5t3sXEx1H3ATbB4l//nLc1qjS8U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789156939; c=relaxed/simple; bh=AyqGvGY1g7AG/tV6PXev+tNVueShCPn7A/JpZS1IVjs=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Zu8mH3uPOLfwvICnVsPYK/wkr6tCKbEFKrdJ9czplmnbGSu6Ja9SRlg0MZVajwv5diJFeEPhw+wZveUdgwLfpVihoZzqIjOZ/oMMyJtSdoMFRHbzACKWTipp2p5beRlhulZSr0R081dIiHl9J9E5snt4GzP2WEPhn8xRhi/1C+0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=nVTGVv3+; 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="nVTGVv3+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 66A381F000FF; Fri, 11 Sep 2026 20:02:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789156934; bh=whu8mw0pgP+XreMZWItvq0VmKHPelNo5fiPfNx9OOzQ=; h=From:To:Cc:Subject:Date:Reply-To; b=nVTGVv3+lE4JPKsuHr1cVCsWzVbd19rNVnfcPuDA6TtWCx66DaprBG99UkQc+an/S R95I0z0Nragagsmq87f1Taxl5uMaz3Ldc+KwlRaUiMeiAu2MqeWIvCWZRtYT1V9t61 /9uB8g8Osg53nwoqVi2wnwoxt/IwUzk8Uuzwa170= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89664: nfsd: release OPEN-decoded posix ACLs via op_release Date: Fri, 11 Sep 2026 21:45:53 +0200 Message-ID: <2026091147-CVE-2026-89664-148c@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=3617; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=kQhrQX8h7HLl2Yyo7vHKQpGob8obObXPbRzJtlbNyjM=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLIqt/L150ONF/w3bhFxHVP3c+rzw099vNjo3XpNayu U5T2qDzvyOWhUGQiUFWTJHlyzaeo/srDil6GdqehpnDygQyhIGLUwAmYviWYcHlsnyru7qyWiu3 3zzp8uHMp05H8RSG+eUsn27oZ08t/v/jZ++Fx5LZce/0/wMA 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: nfsd: release OPEN-decoded posix ACLs via op_release nfsd4_decode_createhow4() calls nfsd4_decode_fattr4(), which allocates refcounted struct posix_acl objects via posix_acl_alloc() and stores them in open->op_pacl and open->op_dpacl. These pointers must be released once the OPEN compound finishes. When nfsd4_decode_open_claim4() returns a non-seqid-mutating error, the dispatcher short-circuits before op_func runs: nfsd4_proc_compound() if (op->status && op->opnum == OP_OPEN) op->status = nfsd4_open_omfg(...) if (!seqid_mutating_err(ntohl(op->status))) return op->status; /* nfsd4_open() never runs */ ... opdesc->op_release(&op->u) /* must still release op_pacl/op_dpacl */ Before this change OP_OPEN had no .op_release in nfsd4_ops[], and the release pair lived inside nfsd4_open() at its out_err: label. On the short-circuit path nfsd4_open() is never invoked, so both posix_acl refs leak on every malformed OPEN compound that carries valid POSIX ACL createhow4 attributes. Add nfsd4_open_release() and wire it as .op_release for OP_OPEN. posix_acl_release() is NULL-safe, so the single release site covers both the normal path and the nfsd4_open_omfg short-circuit. Remove the matching posix_acl_release() pair from nfsd4_open()'s out_err: label to avoid double-releasing. The compound loop has two encoding branches: nfsd4_encode_operation() for normal ops, and nfsd4_encode_replay() for v4.0 replayed ops. op_release was only called from nfsd4_encode_operation(), so resources attached to op->u leak on the replay path. Move the op_release() call out of nfsd4_encode_operation() and the replay branch, placing it after the if-else in nfsd4_proc_compound(). This gives a single call site in a fairly obviously-correct place, covering both the normal encoding and replay paths. The Linux kernel CVE team has assigned CVE-2026-89664 to this issue. Affected and fixed versions =========================== Issue introduced in 7.0 with commit 5fc51dfc2eb160bd7ab3251ab1767cacf9c8bf05 and fixed in 7.2.4 with commit 5b3a7d7c23c071efe12dd1bc1d2e5f97c4892921 Issue introduced in 7.0 with commit 5fc51dfc2eb160bd7ab3251ab1767cacf9c8bf05 and fixed in 7.3-rc1 with commit 8215892993ea9f5231da4fa9eb42428a286fce8b 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-2026-89664 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/nfsd/nfs4proc.c fs/nfsd/nfs4xdr.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/5b3a7d7c23c071efe12dd1bc1d2e5f97c4892921 https://git.kernel.org/stable/c/8215892993ea9f5231da4fa9eb42428a286fce8b