From owner-dev-commits-src-all@freebsd.org Wed Jul 14 11:51:18 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 3374264A0FC; Wed, 14 Jul 2021 11:51:18 +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 4GPwnf0qNRz4hvC; Wed, 14 Jul 2021 11:51:18 +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 0529115A1D; Wed, 14 Jul 2021 11:51:18 +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 16EBpHPJ052193; Wed, 14 Jul 2021 11:51:17 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 16EBpHeY052192; Wed, 14 Jul 2021 11:51:17 GMT (envelope-from git) Date: Wed, 14 Jul 2021 11:51:17 GMT Message-Id: <202107141151.16EBpHeY052192@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Lutz Donnerhacke Subject: git: 791035c8da5e - stable/13 - libalias: fix divide by zero causing panic 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/stable/13 X-Git-Reftype: branch X-Git-Commit: 791035c8da5e8a693b3b954db67ff50b4f8695cb 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: Wed, 14 Jul 2021 11:51:18 -0000 The branch stable/13 has been updated by donner: URL: https://cgit.FreeBSD.org/src/commit/?id=791035c8da5e8a693b3b954db67ff50b4f8695cb commit 791035c8da5e8a693b3b954db67ff50b4f8695cb Author: Stefan Eßer AuthorDate: 2021-07-10 11:00:56 +0000 Commit: Lutz Donnerhacke CommitDate: 2021-07-14 11:49:21 +0000 libalias: fix divide by zero causing panic The packet_limit can fall to 0, leading to a divide by zero abort in the "packets % packet_limit". An possible solution would be to apply a lower limit of 1 after the calculation of packet_limit, but since any number modulo 1 gives 0, the more efficient solution is to skip the modulo operation for packet_limit <= 1. Reported by: Karl Denninger (cherry picked from commit 58080fbca09fda6d5f011d37059edbca8ceb4c58) --- sys/netinet/libalias/alias_db.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sys/netinet/libalias/alias_db.c b/sys/netinet/libalias/alias_db.c index 783a8ca3baa8..ed222c4133d4 100644 --- a/sys/netinet/libalias/alias_db.c +++ b/sys/netinet/libalias/alias_db.c @@ -1769,7 +1769,7 @@ HouseKeeping(struct libalias *la) * Reduce the amount of house keeping work substantially by * sampling over the packets. */ - if (packets % packet_limit == 0) { + if (packet_limit <= 1 || packets % packet_limit == 0) { time_t now; #ifdef _KERNEL