From owner-dev-commits-src-all@freebsd.org Tue Aug 17 21:15:17 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 2906566BB4C; Tue, 17 Aug 2021 21:15:17 +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 4Gq3hj0VNZz4Rsr; Tue, 17 Aug 2021 21:15:17 +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 ED1AE24AC3; Tue, 17 Aug 2021 21:15:16 +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 17HLFG79076676; Tue, 17 Aug 2021 21:15:16 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 17HLFG8Z076675; Tue, 17 Aug 2021 21:15:16 GMT (envelope-from git) Date: Tue, 17 Aug 2021 21:15:16 GMT Message-Id: <202108172115.17HLFG8Z076675@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: "Alexander V. Chernikov" Subject: git: 406a4b37a24e - stable/13 - [multipath][nhops] Fix random crashes with high route churn rate. MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: melifaro X-Git-Repository: src X-Git-Refname: refs/heads/stable/13 X-Git-Reftype: branch X-Git-Commit: 406a4b37a24e655b8a5d8f3401e636ba43f37978 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: Tue, 17 Aug 2021 21:15:17 -0000 The branch stable/13 has been updated by melifaro: URL: https://cgit.FreeBSD.org/src/commit/?id=406a4b37a24e655b8a5d8f3401e636ba43f37978 commit 406a4b37a24e655b8a5d8f3401e636ba43f37978 Author: Alexander V. Chernikov AuthorDate: 2021-08-01 09:46:05 +0000 Commit: Alexander V. Chernikov CommitDate: 2021-08-17 21:14:42 +0000 [multipath][nhops] Fix random crashes with high route churn rate. When certain multipath route begins flapping really fast, it may result in creating multiple identical nexthop groups. The code responsible for unlinking unused nexthop groups had an implicit assumption that there could be only one nexthop group for the same combination of nexthops with weights. This assumption resulted in always unlinking the first "identical" group, instead of the desired one. Such action, in turn, produced a used-but-unlinked nhg along with freed-and-linked nhg, ending up in random crashes. Similarly, it is possible that multiple identical nexthops gets created in the case of high route churn, resulting in the same problem when deleting one of such nexthops. Fix by matching the nexthop/nexhop group pointer when deleting the item. Reported by: avg (cherry picked from commit 054948bd81bb9e4e32449cf351b62e501b8831ff) --- sys/net/route/nhgrp.c | 2 +- sys/net/route/nhop.c | 2 +- sys/net/route/nhop_utils.h | 23 +++-------------------- 3 files changed, 5 insertions(+), 22 deletions(-) diff --git a/sys/net/route/nhgrp.c b/sys/net/route/nhgrp.c index f6638b12ebea..f40ee3c2981c 100644 --- a/sys/net/route/nhgrp.c +++ b/sys/net/route/nhgrp.c @@ -187,7 +187,7 @@ unlink_nhgrp(struct nh_control *ctl, struct nhgrp_priv *key) NHOPS_WLOCK(ctl); - CHT_SLIST_REMOVE_BYOBJ(&ctl->gr_head, mpath, key, nhg_priv_ret); + CHT_SLIST_REMOVE(&ctl->gr_head, mpath, key, nhg_priv_ret); if (nhg_priv_ret == NULL) { DPRINTF("Unable to find nhop group!"); diff --git a/sys/net/route/nhop.c b/sys/net/route/nhop.c index 0db47db9916e..ab5e393ae56a 100644 --- a/sys/net/route/nhop.c +++ b/sys/net/route/nhop.c @@ -337,7 +337,7 @@ unlink_nhop(struct nh_control *ctl, struct nhop_priv *nh_priv_del) idx = 0; NHOPS_WLOCK(ctl); - CHT_SLIST_REMOVE_BYOBJ(&ctl->nh_head, nhops, nh_priv_del, priv_ret); + CHT_SLIST_REMOVE(&ctl->nh_head, nhops, nh_priv_del, priv_ret); if (priv_ret != NULL) { idx = priv_ret->nh_idx; diff --git a/sys/net/route/nhop_utils.h b/sys/net/route/nhop_utils.h index a0d7cd564e72..1f56f4cb8b0b 100644 --- a/sys/net/route/nhop_utils.h +++ b/sys/net/route/nhop_utils.h @@ -115,31 +115,13 @@ struct _HNAME##_head { \ (_head)->items_count++; \ } while(0) -#define CHT_SLIST_REMOVE(_head, _PX, _key, _ret) do { \ - typeof(*(_head)->ptr) _tmp; \ - uint32_t _buck = CHT_GET_BUCK(_head, _PX, _key); \ - _ret = CHT_FIRST(_head, _buck); \ - _tmp = NULL; \ - for ( ; _ret != NULL; _tmp = _ret, _ret = _PX##_next(_ret)) { \ - if (_PX##_cmp(_key, _ret)) \ - break; \ - } \ - if (_ret != NULL) { \ - if (_tmp == NULL) \ - CHT_FIRST(_head, _buck) = _PX##_next(_ret); \ - else \ - _PX##_next(_tmp) = _PX##_next(_ret); \ - (_head)->items_count--; \ - } \ -} while(0) - -#define CHT_SLIST_REMOVE_BYOBJ(_head, _PX, _obj, _ret) do { \ +#define CHT_SLIST_REMOVE(_head, _PX, _obj, _ret) do { \ typeof(*(_head)->ptr) _tmp; \ uint32_t _buck = CHT_GET_BUCK_OBJ(_head, _PX, _obj); \ _ret = CHT_FIRST(_head, _buck); \ _tmp = NULL; \ for ( ; _ret != NULL; _tmp = _ret, _ret = _PX##_next(_ret)) { \ - if (_PX##_cmp(_obj, _ret)) \ + if (_obj == _ret) \ break; \ } \ if (_ret != NULL) { \ @@ -150,6 +132,7 @@ struct _HNAME##_head { \ (_head)->items_count--; \ } \ } while(0) +#define CHT_SLIST_REMOVE_BYOBJ CHT_SLIST_REMOVE #define CHT_SLIST_FOREACH(_head, _PX, _x) \ for (uint32_t _i = 0; _i < (_head)->hash_size; _i++) { \