From patchwork Mon Mar 30 07:28:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Kubecek X-Patchwork-Id: 221595 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C870BC2D0EF for ; Mon, 30 Mar 2020 07:37:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9E5E220784 for ; Mon, 30 Mar 2020 07:37:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729543AbgC3HhM (ORCPT ); Mon, 30 Mar 2020 03:37:12 -0400 Received: from lion.mk-sys.cz ([213.168.178.121]:35846 "EHLO lion.mk-sys.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729420AbgC3HhK (ORCPT ); Mon, 30 Mar 2020 03:37:10 -0400 X-Greylist: delayed 501 seconds by postgrey-1.27 at vger.kernel.org; Mon, 30 Mar 2020 03:37:10 EDT Received: by lion.mk-sys.cz (Postfix, from userid 1000) id 4D88E604C0; Mon, 30 Mar 2020 09:28:44 +0200 (CEST) From: Michal Kubecek Subject: [PATCH ethtool] netlink: show netlink error even without extack To: John Linville , netdev@vger.kernel.org Message-Id: <20200330072844.4D88E604C0@lion.mk-sys.cz> Date: Mon, 30 Mar 2020 09:28:44 +0200 (CEST) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Even if the NLMSG_ERROR message has no extack (NLM_F_ACK_TLVS not set, i.e. no error/warning message and bad attribute offset), we still want to display the error code (unless suppressed) and, if pretty printing is enabled, the embedded client message (if present). Fixes: 50efb3cdd2bb ("netlink: netlink socket wrapper and helpers") Signed-off-by: Michal Kubecek --- netlink/nlsock.c | 37 +++++++++++++++++-------------------- 1 file changed, 17 insertions(+), 20 deletions(-) diff --git a/netlink/nlsock.c b/netlink/nlsock.c index 22abb68b6646..2c760b770ec5 100644 --- a/netlink/nlsock.c +++ b/netlink/nlsock.c @@ -173,25 +173,25 @@ static int nlsock_process_ack(struct nlmsghdr *nlhdr, ssize_t len, { const struct nlattr *tb[NLMSGERR_ATTR_MAX + 1] = {}; DECLARE_ATTR_TB_INFO(tb); + unsigned int err_offset = 0; unsigned int tlv_offset; struct nlmsgerr *nlerr; bool silent; - if (len < NLMSG_HDRLEN + sizeof(*nlerr)) + if ((len < NLMSG_HDRLEN + sizeof(*nlerr)) || (len < nlhdr->nlmsg_len)) return -EFAULT; nlerr = mnl_nlmsg_get_payload(nlhdr); - silent = (!(nlhdr->nlmsg_flags & NLM_F_ACK_TLVS) || - suppress_nlerr >= 2 || - (suppress_nlerr && nlerr->error == -EOPNOTSUPP)); - if (silent) - goto out; + silent = suppress_nlerr >= 2 || + (suppress_nlerr && nlerr->error == -EOPNOTSUPP); + if (silent || !(nlhdr->nlmsg_flags & NLM_F_ACK_TLVS)) + goto tlv_done; tlv_offset = sizeof(*nlerr); if (!(nlhdr->nlmsg_flags & NLM_F_CAPPED)) tlv_offset += MNL_ALIGN(mnl_nlmsg_get_payload_len(&nlerr->msg)); - if (mnl_attr_parse(nlhdr, tlv_offset, attr_cb, &tb_info) < 0) - goto out; + goto tlv_done; + if (tb[NLMSGERR_ATTR_MSG]) { const char *msg = mnl_attr_get_str(tb[NLMSGERR_ATTR_MSG]); @@ -202,24 +202,21 @@ static int nlsock_process_ack(struct nlmsghdr *nlhdr, ssize_t len, mnl_attr_get_u32(tb[NLMSGERR_ATTR_OFFS])); fputc('\n', stderr); } + if (tb[NLMSGERR_ATTR_OFFS]) + err_offset = mnl_attr_get_u32(tb[NLMSGERR_ATTR_OFFS]); - if (nlerr->error && pretty) { - unsigned int err_offset = 0; - - if (tb[NLMSGERR_ATTR_OFFS]) - err_offset = mnl_attr_get_u32(tb[NLMSGERR_ATTR_OFFS]); +tlv_done: + if (nlerr->error && !silent) { + errno = -nlerr->error; + perror("netlink error"); + } + if (pretty && !(nlhdr->nlmsg_flags & NLM_F_CAPPED) && + nlhdr->nlmsg_len >= NLMSG_HDRLEN + nlerr->msg.nlmsg_len) { fprintf(stderr, "offending message%s:\n", err_offset ? " and attribute" : ""); pretty_print_genlmsg(&nlerr->msg, ethnl_umsg_desc, ethnl_umsg_n_desc, err_offset); } - -out: - if (nlerr->error) { - errno = -nlerr->error; - if (!silent) - perror("netlink error"); - } return nlerr->error; }