From owner-svn-src-head@freebsd.org Tue Apr 23 17:18:22 2019 Return-Path: Delivered-To: svn-src-head@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 9A29815A02EE; Tue, 23 Apr 2019 17:18:22 +0000 (UTC) (envelope-from cem@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 3740982B1B; Tue, 23 Apr 2019 17:18:22 +0000 (UTC) (envelope-from cem@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 089D8279AC; Tue, 23 Apr 2019 17:18:21 +0000 (UTC) (envelope-from cem@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x3NHIKmv099949; Tue, 23 Apr 2019 17:18:20 GMT (envelope-from cem@FreeBSD.org) Received: (from cem@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x3NHIKgS099948; Tue, 23 Apr 2019 17:18:20 GMT (envelope-from cem@FreeBSD.org) Message-Id: <201904231718.x3NHIKgS099948@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: cem set sender to cem@FreeBSD.org using -f From: Conrad Meyer Date: Tue, 23 Apr 2019 17:18:20 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r346601 - head/sys/netinet6 X-SVN-Group: head X-SVN-Commit-Author: cem X-SVN-Commit-Paths: head/sys/netinet6 X-SVN-Commit-Revision: 346601 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 3740982B1B X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-2.95 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; NEURAL_HAM_SHORT(-0.95)[-0.954,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US]; NEURAL_HAM_LONG(-1.00)[-1.000,0] X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 23 Apr 2019 17:18:22 -0000 Author: cem Date: Tue Apr 23 17:18:20 2019 New Revision: 346601 URL: https://svnweb.freebsd.org/changeset/base/346601 Log: ip6_randomflowlabel: Avoid blocking if random(4) is not available If kern.random.initial_seeding.bypass_before_seeding is disabled, random(4) and arc4random(9) will block indefinitely until enough entropy is available to initially seed Fortuna. It seems that zero flowids are perfectly valid, so avoid blocking on random until initial seeding takes place. Discussed with: bz (earlier revision) Reviewed by: thj Sponsored by: Dell EMC Isilon Differential Revision: https://reviews.freebsd.org/D20011 Modified: head/sys/netinet6/ip6_id.c Modified: head/sys/netinet6/ip6_id.c ============================================================================== --- head/sys/netinet6/ip6_id.c Tue Apr 23 17:11:45 2019 (r346600) +++ head/sys/netinet6/ip6_id.c Tue Apr 23 17:18:20 2019 (r346601) @@ -89,6 +89,7 @@ __FBSDID("$FreeBSD$"); #include #include #include +#include #include #include @@ -257,6 +258,16 @@ ip6_randomid(void) u_int32_t ip6_randomflowlabel(void) { + + /* + * It's ok to emit zero flow labels early, before random is available + * (seeded). RFC 6437: + * + * "A Flow Label of zero is used to indicate packets that have not been + * labeled." + */ + if (__predict_false(!is_random_seeded())) + return (0); return randomid(&randomtab_20) & 0xfffff; }