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 A329844E045 for ; Fri, 11 Sep 2026 20:03:09 +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=1789157004; cv=none; b=ZKgRz/rG/q3StcPYE2SAuaZh7DT6KcaR6tsQVt2C5gHj3tPXsBfSMaaPVa2S/2tzs0gPI7LXx+fJi80+an0qLdvQqqtGMwCnOxcWptW7KSNwOSd4z+R4GlLoTGmloUpTSKXkirRXdrNCBme0Yx+0CS+Pj8nhxfLe8z+LDNxxab8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789157004; c=relaxed/simple; bh=BVTPZDbf073o7Ran/KW8TO2/881Vf/Yt0Qbai1qsxSE=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=uwjopxLY39U9FSlyBRpVh2FvpCX+KSqwYl4s+P7Q4UGgSFrXNZew97pjTy84rSZKz1TFtVJBKiU6qb/DQvX/kVH/gJsp24Z1B4bmrvvaiXBBDqCEDylPsKSKHm2R0vi+2C2nz0f18h7tHnqVds5YmtlQvcoXs9itKgRxtIgLBxI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=nY65NZUA; 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="nY65NZUA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3B8161F00893; Fri, 11 Sep 2026 20:03:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789156989; bh=mZT0RuFuCEXzE64uhVegt1mK62BRNE01GYNBCipa/Pc=; h=From:To:Cc:Subject:Date:Reply-To; b=nY65NZUArMh8JKbKQawX98iSqbFyjl2I2QLX3TlofSKWddNz17fgK2vKCVI7R2flq PdT5df70WHpbsWUV78zRZMmlEiuIWe+l24HXkpPOiTeaWjv4Z0PABoTwZ4h5uFS+yo P87FAeGH81yPCST7JI9FwNVifh1GmKrehBE/A1PQ= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89698: nfsd: widen nfsd_genl_rqstp address fields to sockaddr_storage Date: Fri, 11 Sep 2026 21:46:27 +0200 Message-ID: <2026091155-CVE-2026-89698-0a54@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=3016; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=Xt1a5xj+4taMroQZLwKpLFZQS+KkLwygN0NTMzptdDY=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLIpsDtROsL4jtOuNg7O4YK+Fps6fwfyDX9v+qM6elu XxPX8TUEcvCIMjEICumyPJlG8/R/RWHFL0MbU/DzGFlAhnCwMUpABPZ/pBhwdp1C7tPTc6Jctpn cbYxSYPbtM1lCsP86GutIVJ9v26u4JP5sEzikFjPAbsWAA== 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: widen nfsd_genl_rqstp address fields to sockaddr_storage struct nfsd_genl_rqstp declares rq_daddr and rq_saddr as plain "struct sockaddr" (16 bytes). When an IPv6 NFS client is connected, nfsd_genl_rpc_status_compose_msg() casts these fields to "struct sockaddr_in6 *" (28 bytes) and reads sin6_addr at offset 8..24, which extends 8 bytes past the end of the 16-byte sockaddr field into the adjacent rq_flags member. The 16-byte nla_put_in6_addr then ships 8 bytes of truncated IPv6 address followed by 8 bytes of rq_flags to userspace via the NFSD_A_RPC_STATUS_SADDR6/DADDR6 netlink attributes. This is reachable by any unprivileged process in the network namespace because NFSD_CMD_RPC_STATUS_GET uses GENL_CMD_CAP_DUMP without GENL_ADMIN_PERM. Fix by widening rq_daddr and rq_saddr to struct sockaddr_storage so the IPv6 casts operate within bounds, copying sizeof(struct sockaddr_storage) bytes in the memcpy calls so the full address is captured, and zero-initializing the genl_rqstp stack variable to prevent leaking uninitialized tail bytes through netlink. The Linux kernel CVE team has assigned CVE-2026-89698 to this issue. Affected and fixed versions =========================== Issue introduced in 6.7 with commit bd9d6a3efa9709e653aafbeb859289feccb8e70c and fixed in 6.18.51 with commit 03c512f22d3fbe7a3767d6df5e3d88b8e7c105e5 Issue introduced in 6.7 with commit bd9d6a3efa9709e653aafbeb859289feccb8e70c and fixed in 7.2.4 with commit dcb69ad0dafb4a24b825183bb94055d5be8a10bd Issue introduced in 6.7 with commit bd9d6a3efa9709e653aafbeb859289feccb8e70c and fixed in 7.3-rc1 with commit a99d720ed2a5258564e5e9d5f39f3184a030d354 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-2026-89698 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/nfsctl.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/03c512f22d3fbe7a3767d6df5e3d88b8e7c105e5 https://git.kernel.org/stable/c/dcb69ad0dafb4a24b825183bb94055d5be8a10bd https://git.kernel.org/stable/c/a99d720ed2a5258564e5e9d5f39f3184a030d354