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 D6AD7576EBB; Wed, 9 Sep 2026 14:39:05 +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=1788964747; cv=none; b=LKRr1i48HEmnhvIDLIpJPeIr6n1a7r5EAt4IYNJkEHdIq1Z0mzDSssvSTANkDb2Hg15cIqAf5uuJm6s6zQ+DoXx0vo7IoLRi+oHDeWWeeMqXLGwfCbv4B8/kNnGbMQtA9JUXwzZDMmsW/o5INAM/pCJ5P3Ocz+sE8MRw4H26tIc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788964747; c=relaxed/simple; bh=27oWdsuz+80wYd8LCFKq0YAvS9IWBiSNewaqhizxdtM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WdxlU9YsCgRKdKkmfRXzefb/Zw8zGCEvYtJPfFx61rHlmWgG82G9WCCNIxutoX+I47KDppi/6M+j8qZ6vKj34j6cWVsbKsVLvUWKFJgdH0v6YHq2zoSQHC38k+nvkn/ZZKrQZ/5njl1IBFSHiuNJh6b6xvVeLXDX2oEqYKMYHj8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=tp6qEg4Q; 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="tp6qEg4Q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3A2A31F00A3A; Wed, 9 Sep 2026 14:39:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788964745; bh=9XbRnqTCCdPA8y2jJN6SiDiXJzw+x+zVqtvmzWW6aAw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=tp6qEg4Qe8TEJvjnt3PcTMlBFpB3o/bK1Bd9d7RYpBiUR6GIBSJaSXDKQsnkclpCs pWHnZlLvtw05ELSPJKMR3H3wVboEQoJUJGzWkGaFw5kZG4ZI4O0z19jvRcb+PRL7UY j7A3tPAiK7I7hJKA0BpcqwtRpw+8wpfTYhkOxzZ0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jeff Layton , Chuck Lever , Sasha Levin Subject: [PATCH 6.18 530/583] nfsd: widen nfsd_genl_rqstp address fields to sockaddr_storage Date: Wed, 9 Sep 2026 15:43:35 +0200 Message-ID: <20260909134256.165767255@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260909134237.773280130@linuxfoundation.org> References: <20260909134237.773280130@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jeff Layton commit a99d720ed2a5258564e5e9d5f39f3184a030d354 upstream. 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. Fixes: bd9d6a3efa97 ("NFSD: add rpc_status netlink support") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20260602-nfsd-testing-v2-5-e4ea62e3cd5c@kernel.org Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/nfsctl.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -1412,8 +1412,8 @@ static int create_proc_exports_entry(voi unsigned int nfsd_net_id; struct nfsd_genl_rqstp { - struct sockaddr rq_daddr; - struct sockaddr rq_saddr; + struct sockaddr_storage rq_daddr; + struct sockaddr_storage rq_saddr; unsigned long rq_flags; ktime_t rq_stime; __be32 rq_xid; @@ -1448,7 +1448,7 @@ static int nfsd_genl_rpc_status_compose_ NFSD_A_RPC_STATUS_PAD)) goto out_cancel; - switch (genl_rqstp->rq_saddr.sa_family) { + switch (genl_rqstp->rq_saddr.ss_family) { case AF_INET: { const struct sockaddr_in *s_in, *d_in; @@ -1539,7 +1539,7 @@ int nfsd_nl_rpc_status_get_dumpit(struct list_for_each_entry_rcu(rqstp, &nn->nfsd_serv->sv_pools[i].sp_all_threads, rq_all) { - struct nfsd_genl_rqstp genl_rqstp; + struct nfsd_genl_rqstp genl_rqstp = {}; unsigned int status_counter; if (rqstp_index++ < thread_skip) /* already consumed */ @@ -1563,9 +1563,9 @@ int nfsd_nl_rpc_status_get_dumpit(struct genl_rqstp.rq_stime = rqstp->rq_stime; genl_rqstp.rq_opcnt = 0; memcpy(&genl_rqstp.rq_daddr, svc_daddr(rqstp), - sizeof(struct sockaddr)); + sizeof(struct sockaddr_storage)); memcpy(&genl_rqstp.rq_saddr, svc_addr(rqstp), - sizeof(struct sockaddr)); + sizeof(struct sockaddr_storage)); #ifdef CONFIG_NFSD_V4 if (rqstp->rq_vers == NFS4_VERSION &&