From owner-svn-src-all@freebsd.org Wed May 8 16:04:34 2019 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 24C8A158BA0C; Wed, 8 May 2019 16:04:34 +0000 (UTC) (envelope-from markj@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id BF46F82702; Wed, 8 May 2019 16:04:33 +0000 (UTC) (envelope-from markj@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id AB1458189; Wed, 8 May 2019 16:04:33 +0000 (UTC) (envelope-from markj@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x48G4Xop024404; Wed, 8 May 2019 16:04:33 GMT (envelope-from markj@FreeBSD.org) Received: (from markj@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x48G4X4x024403; Wed, 8 May 2019 16:04:33 GMT (envelope-from markj@FreeBSD.org) Message-Id: <201905081604.x48G4X4x024403@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: markj set sender to markj@FreeBSD.org using -f From: Mark Johnston Date: Wed, 8 May 2019 16:04:33 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-12@freebsd.org Subject: svn commit: r347349 - stable/12/usr.sbin/rtadvd X-SVN-Group: stable-12 X-SVN-Commit-Author: markj X-SVN-Commit-Paths: stable/12/usr.sbin/rtadvd X-SVN-Commit-Revision: 347349 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: BF46F82702 X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-2.97 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-1.00)[-0.999,0]; NEURAL_HAM_SHORT(-0.98)[-0.976,0]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US] X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 08 May 2019 16:04:34 -0000 Author: markj Date: Wed May 8 16:04:33 2019 New Revision: 347349 URL: https://svnweb.freebsd.org/changeset/base/347349 Log: MFC r346960: Retry upon NET_RT_IFLIST sysctl failure. PR: 195191 Modified: stable/12/usr.sbin/rtadvd/if.c Directory Properties: stable/12/ (props changed) Modified: stable/12/usr.sbin/rtadvd/if.c ============================================================================== --- stable/12/usr.sbin/rtadvd/if.c Wed May 8 16:01:59 2019 (r347348) +++ stable/12/usr.sbin/rtadvd/if.c Wed May 8 16:04:33 2019 (r347349) @@ -408,6 +408,8 @@ update_ifinfo_nd_flags(struct ifinfo *ifi) return (0); } +#define MAX_SYSCTL_TRY 5 + struct ifinfo * update_ifinfo(struct ifilist_head_t *ifi_head, int ifindex) { @@ -419,26 +421,43 @@ update_ifinfo(struct ifilist_head_t *ifi_head, int ifi size_t len; char *lim; int mib[] = { CTL_NET, PF_ROUTE, 0, AF_INET6, NET_RT_IFLIST, 0 }; - int error; + int error, ntry; syslog(LOG_DEBUG, "<%s> enter", __func__); - if (sysctl(mib, sizeof(mib)/sizeof(mib[0]), NULL, &len, NULL, 0) < - 0) { - syslog(LOG_ERR, - "<%s> sysctl: NET_RT_IFLIST size get failed", __func__); - exit(1); - } - if ((msg = malloc(len)) == NULL) { - syslog(LOG_ERR, "<%s> malloc failed", __func__); - exit(1); - } - if (sysctl(mib, sizeof(mib)/sizeof(mib[0]), msg, &len, NULL, 0) < - 0) { - syslog(LOG_ERR, - "<%s> sysctl: NET_RT_IFLIST get failed", __func__); - exit(1); - } + ntry = 0; + do { + /* + * We'll try to get addresses several times in case that + * the number of addresses is unexpectedly increased during + * the two sysctl calls. This should rarely happen. + * Portability note: since FreeBSD does not add margin of + * memory at the first sysctl, the possibility of failure on + * the second sysctl call is a bit higher. + */ + + if (sysctl(mib, nitems(mib), NULL, &len, NULL, 0) < 0) { + syslog(LOG_ERR, + "<%s> sysctl: NET_RT_IFLIST size get failed", + __func__); + exit(1); + } + if ((msg = malloc(len)) == NULL) { + syslog(LOG_ERR, "<%s> malloc failed", __func__); + exit(1); + } + if (sysctl(mib, nitems(mib), msg, &len, NULL, 0) < 0) { + if (errno != ENOMEM || ++ntry >= MAX_SYSCTL_TRY) { + free(msg); + syslog(LOG_ERR, + "<%s> sysctl: NET_RT_IFLIST get failed", + __func__); + exit(1); + } + free(msg); + msg = NULL; + } + } while (msg == NULL); lim = msg + len; for (ifm = (struct if_msghdr *)msg;