From patchwork Sun Sep 3 15:21:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?0L3QsNCx?= X-Patchwork-Id: 13373278 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A74EEC83F2C for ; Sun, 3 Sep 2023 15:22:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231415AbjICPWB (ORCPT ); Sun, 3 Sep 2023 11:22:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37208 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229970AbjICPWB (ORCPT ); Sun, 3 Sep 2023 11:22:01 -0400 Received: from tarta.nabijaczleweli.xyz (tarta.nabijaczleweli.xyz [139.28.40.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 67491F1 for ; Sun, 3 Sep 2023 08:21:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=nabijaczleweli.xyz; s=202305; t=1693754513; bh=QMeZnV04dYfGiix7AosDHMUI3cZ6F+Vt4zBwig3niN8=; h=Date:From:To:Subject:From; b=pqk2GZEup8UyGYH4bRlbMqRp3WPaCkgJuGPQvF5Dl4HnYBgyAGsVLbFkKOh6vJgCO pYTH6NRwziCvGqyq9gavF9AJHC1LqjQJ5PKyJrg7RvfKO7X0KAmnqWOpCLTNo42RCv jjHUNvHfenTsGV2AJXidnAhkESqTrIymeoTq0teKrQ56CF7WexCUeccepUyWfrk+ul MY/w/+phxl9YrnQiMmvpoFjNcmbwv2VzNWcYvm8F2OVV3u8NjfD9e/+NVl59T0poXt P67oMmsfEOvJ0sRcU9+UyEnqFYmJBELLspJL7UJZSZLjtBiCOp+okBeloVgQdqwOlo yXmU4rMOcF0GQ== Received: from tarta.nabijaczleweli.xyz (unknown [192.168.1.250]) by tarta.nabijaczleweli.xyz (Postfix) with ESMTPSA id 9B989B434 for ; Sun, 3 Sep 2023 17:21:53 +0200 (CEST) Date: Sun, 3 Sep 2023 17:21:52 +0200 From: Ahelenia =?utf-8?q?Ziemia=C5=84ska?= To: linux-nfs@vger.kernel.org Subject: [PATCH nfs-utils 1/2] fsidd: call anonymous sockets by their name only, don't fill with NULs to 108 bytes Message-ID: <04f3fe71defa757d518468f04f08334a5d0dfbb9.1693754442.git.nabijaczleweli@nabijaczleweli.xyz> MIME-Version: 1.0 Content-Disposition: inline User-Agent: NeoMutt/20230517 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Since e00ab3c0616fe6d83ab0710d9e7d989c299088f7, ss -l looks like this: u_seq LISTEN 0 5 @/run/fsid.sock@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 26989379 * 0 with fsidd pushing all the addresses to 108 bytes wide, which is deeply egregious if you don't filter it out and recolumnate. This is because, naturally (unix(7)), "Null bytes in the name have no special significance": abstract addresses are binary blobs, but paths automatically terminate at the first NUL byte, since paths can't contain those. So just specify the correct address length when we're using the abstract domain: unix(7) recommends "offsetof(struct sockaddr_un, sun_path) + strlen(sun_path) + 1" for paths, but we don't want to include the terminating NUL, so it's just "offsetof(struct sockaddr_un, sun_path) + strlen(sun_path)". This brings the width back to order: -- >8 -- $ ss -la | grep @ u_str ESTAB 0 0 @45208536ec96909a/bus/systemd-timesyn/bus-api-timesync 18500238 * 18501249 u_str ESTAB 0 0 @fecc9657d2315eb7/bus/systemd-network/bus-api-network 18495452 * 18494406 u_seq LISTEN 0 5 @/run/fsid.sock 27168796 * 0 u_str ESTAB 0 0 @ac308f35f50797a2/bus/systemd-logind/system 19406 * 15153 u_str ESTAB 0 0 @b6606e0dfacbae75/bus/systemd/bus-api-system 18494353 * 18495334 u_str ESTAB 0 0 @5880653d215718a7/bus/systemd/bus-system 26930876 * 26930003 -- >8 -- Fixes: e00ab3c0616fe6d83ab0710d9e7d989c299088f7 ("fsidd: provide better default socket name.") Signed-off-by: Ahelenia Ziemiańska --- support/reexport/fsidd.c | 8 +++++--- support/reexport/reexport.c | 7 +++++-- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/support/reexport/fsidd.c b/support/reexport/fsidd.c index d4b245e8..4c377415 100644 --- a/support/reexport/fsidd.c +++ b/support/reexport/fsidd.c @@ -171,10 +171,12 @@ int main(void) memset(&addr, 0, sizeof(struct sockaddr_un)); addr.sun_family = AF_UNIX; strncpy(addr.sun_path, sock_file, sizeof(addr.sun_path) - 1); - if (addr.sun_path[0] == '@') + socklen_t addr_len = sizeof(struct sockaddr_un); + if (addr.sun_path[0] == '@') { /* "abstract" socket namespace */ + addr_len = offsetof(struct sockaddr_un, sun_path) + strlen(addr.sun_path); addr.sun_path[0] = 0; - else + } else unlink(sock_file); srv = socket(AF_UNIX, SOCK_SEQPACKET | SOCK_NONBLOCK, 0); @@ -183,7 +185,7 @@ int main(void) return 1; } - if (bind(srv, (const struct sockaddr *)&addr, sizeof(struct sockaddr_un)) == -1) { + if (bind(srv, (const struct sockaddr *)&addr, addr_len) == -1) { xlog(L_WARNING, "Unable to bind %s: %m\n", sock_file); return 1; } diff --git a/support/reexport/reexport.c b/support/reexport/reexport.c index d9a700af..b7ee6f46 100644 --- a/support/reexport/reexport.c +++ b/support/reexport/reexport.c @@ -40,9 +40,12 @@ static bool connect_fsid_service(void) memset(&addr, 0, sizeof(struct sockaddr_un)); addr.sun_family = AF_UNIX; strncpy(addr.sun_path, sock_file, sizeof(addr.sun_path) - 1); - if (addr.sun_path[0] == '@') + socklen_t addr_len = sizeof(struct sockaddr_un); + if (addr.sun_path[0] == '@') { /* "abstract" socket namespace */ + addr_len = offsetof(struct sockaddr_un, sun_path) + strlen(addr.sun_path); addr.sun_path[0] = 0; + } s = socket(AF_UNIX, SOCK_SEQPACKET, 0); if (s == -1) { @@ -50,7 +53,7 @@ static bool connect_fsid_service(void) return false; } - ret = connect(s, (const struct sockaddr *)&addr, sizeof(struct sockaddr_un)); + ret = connect(s, (const struct sockaddr *)&addr, addr_len); if (ret == -1) { xlog(L_WARNING, "Unable to connect %s: %m, is fsidd running?\n", sock_file); return false;