From owner-dev-commits-src-all@freebsd.org Fri Jul 2 22:32:30 2021 Return-Path: Delivered-To: dev-commits-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id F3A48673C80; Fri, 2 Jul 2021 22:32:30 +0000 (UTC) (envelope-from git@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) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4GGqb26Y01z4XYw; Fri, 2 Jul 2021 22:32:30 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id CA1751C706; Fri, 2 Jul 2021 22:32:30 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 162MWUCG049890; Fri, 2 Jul 2021 22:32:30 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 162MWUIY049889; Fri, 2 Jul 2021 22:32:30 GMT (envelope-from git) Date: Fri, 2 Jul 2021 22:32:30 GMT Message-Id: <202107022232.162MWUIY049889@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Lutz Donnerhacke Subject: git: 25392fac9488 - main - libalias: Fix splay comparsion bug MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: donner X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 25392fac9488bcae5c451500df2e2945430484a6 Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-all@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for all branches of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 02 Jul 2021 22:32:31 -0000 The branch main has been updated by donner: URL: https://cgit.FreeBSD.org/src/commit/?id=25392fac9488bcae5c451500df2e2945430484a6 commit 25392fac9488bcae5c451500df2e2945430484a6 Author: Lutz Donnerhacke AuthorDate: 2021-07-02 21:41:25 +0000 Commit: Lutz Donnerhacke CommitDate: 2021-07-02 22:31:53 +0000 libalias: Fix splay comparsion bug Comparing elements in a tree requires transitiviy. If a < b and b < c then a must be smaller than c. This way the tree elements are always pairwise comparable. Tristate comparsion functions returning values lower, equal, or greater than zero, are usually implemented by a simple subtraction of the operands. If the size of the operands are equal to the size of the result, integer modular arithmetics kick in and violates the transitivity. Example: Working on byte with 0, 120, and 240. Now computing the differences: 120 - 0 = 120 240 - 120 = 120 240 - 0 = -16 MFC after: 3 days --- sys/netinet/libalias/alias_db.h | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/sys/netinet/libalias/alias_db.h b/sys/netinet/libalias/alias_db.h index ec0b69c01f82..971ca305c1a6 100644 --- a/sys/netinet/libalias/alias_db.h +++ b/sys/netinet/libalias/alias_db.h @@ -351,10 +351,10 @@ static inline int cmp_out(struct alias_link *a, struct alias_link *b) { int i = a->src_port - b->src_port; if (i != 0) return (i); - i = a->src_addr.s_addr - b->src_addr.s_addr; - if (i != 0) return (i); - i = a->dst_addr.s_addr - b->dst_addr.s_addr; - if (i != 0) return (i); + if (a->src_addr.s_addr > b->src_addr.s_addr) return (1); + if (a->src_addr.s_addr < b->src_addr.s_addr) return (-1); + if (a->dst_addr.s_addr > b->dst_addr.s_addr) return (1); + if (a->dst_addr.s_addr < b->dst_addr.s_addr) return (-1); i = a->dst_port - b->dst_port; if (i != 0) return (i); i = a->link_type - b->link_type; @@ -368,8 +368,9 @@ cmp_in(struct group_in *a, struct group_in *b) { if (i != 0) return (i); i = a->link_type - b->link_type; if (i != 0) return (i); - i = a->alias_addr.s_addr - b->alias_addr.s_addr; - return (i); + if (a->alias_addr.s_addr > b->alias_addr.s_addr) return (1); + if (a->alias_addr.s_addr < b->alias_addr.s_addr) return (-1); + return (0); } SPLAY_PROTOTYPE(splay_in, group_in, in, cmp_in);