From patchwork Thu Sep 9 14:03:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Westphal X-Patchwork-Id: 509190 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 05B2AC433F5 for ; Thu, 9 Sep 2021 14:40:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DACFD61215 for ; Thu, 9 Sep 2021 14:40:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242608AbhIIOlj (ORCPT ); Thu, 9 Sep 2021 10:41:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46366 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346692AbhIIOld (ORCPT ); Thu, 9 Sep 2021 10:41:33 -0400 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [IPv6:2a0a:51c0:0:12e:520::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 12271C06642B; Thu, 9 Sep 2021 07:04:02 -0700 (PDT) Received: from fw by Chamillionaire.breakpoint.cc with local (Exim 4.92) (envelope-from ) id 1mOKem-0003yH-KJ; Thu, 09 Sep 2021 16:04:00 +0200 From: Florian Westphal To: stable@vger.kernel.org Cc: , Pablo Neira Ayuso , Laura Garcia Liebana , Florian Westphal Subject: [PATCH 5.10.y 3/3] netfilter: nftables: clone set element expression template Date: Thu, 9 Sep 2021 16:03:37 +0200 Message-Id: <20210909140337.29707-4-fw@strlen.de> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210909140337.29707-1-fw@strlen.de> References: <20210909140337.29707-1-fw@strlen.de> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Pablo Neira Ayuso commit 4d8f9065830e526c83199186c5f56a6514f457d2 upstream. memcpy() breaks when using connlimit in set elements. Use nft_expr_clone() to initialize the connlimit expression list, otherwise connlimit garbage collector crashes when walking on the list head copy. [ 493.064656] Workqueue: events_power_efficient nft_rhash_gc [nf_tables] [ 493.064685] RIP: 0010:find_or_evict+0x5a/0x90 [nf_conncount] [ 493.064694] Code: 2b 43 40 83 f8 01 77 0d 48 c7 c0 f5 ff ff ff 44 39 63 3c 75 df 83 6d 18 01 48 8b 43 08 48 89 de 48 8b 13 48 8b 3d ee 2f 00 00 <48> 89 42 08 48 89 10 48 b8 00 01 00 00 00 00 ad de 48 89 03 48 83 [ 493.064699] RSP: 0018:ffffc90000417dc0 EFLAGS: 00010297 [ 493.064704] RAX: 0000000000000000 RBX: ffff888134f38410 RCX: 0000000000000000 [ 493.064708] RDX: 0000000000000000 RSI: ffff888134f38410 RDI: ffff888100060cc0 [ 493.064711] RBP: ffff88812ce594a8 R08: ffff888134f38438 R09: 00000000ebb9025c [ 493.064714] R10: ffffffff8219f838 R11: 0000000000000017 R12: 0000000000000001 [ 493.064718] R13: ffffffff82146740 R14: ffff888134f38410 R15: 0000000000000000 [ 493.064721] FS: 0000000000000000(0000) GS:ffff88840e440000(0000) knlGS:0000000000000000 [ 493.064725] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 493.064729] CR2: 0000000000000008 CR3: 00000001330aa002 CR4: 00000000001706e0 [ 493.064733] Call Trace: [ 493.064737] nf_conncount_gc_list+0x8f/0x150 [nf_conncount] [ 493.064746] nft_rhash_gc+0x106/0x390 [nf_tables] Reported-by: Laura Garcia Liebana Fixes: 409444522976 ("netfilter: nf_tables: add elements with stateful expressions") Signed-off-by: Pablo Neira Ayuso Signed-off-by: Florian Westphal --- net/netfilter/nf_tables_api.c | 36 +++++++++++++++++++++++++++-------- 1 file changed, 28 insertions(+), 8 deletions(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 3942a29413a4..2b5f97e1d40b 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -5150,6 +5150,24 @@ static void nf_tables_set_elem_destroy(const struct nft_ctx *ctx, kfree(elem); } +static int nft_set_elem_expr_setup(struct nft_ctx *ctx, + const struct nft_set_ext *ext, + struct nft_expr *expr) +{ + struct nft_expr *elem_expr = nft_set_ext_expr(ext); + int err; + + if (expr == NULL) + return 0; + + err = nft_expr_clone(elem_expr, expr); + if (err < 0) + return -ENOMEM; + + nft_expr_destroy(ctx, expr); + return 0; +} + static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set, const struct nlattr *attr, u32 nlmsg_flags) { @@ -5352,15 +5370,17 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set, *nft_set_ext_obj(ext) = obj; obj->use++; } - if (expr) { - memcpy(nft_set_ext_expr(ext), expr, expr->ops->size); - kfree(expr); - expr = NULL; - } + + err = nft_set_elem_expr_setup(ctx, ext, expr); + if (err < 0) + goto err_elem_expr; + expr = NULL; trans = nft_trans_elem_alloc(ctx, NFT_MSG_NEWSETELEM, set); - if (trans == NULL) - goto err_trans; + if (trans == NULL) { + err = -ENOMEM; + goto err_elem_expr; + } ext->genmask = nft_genmask_cur(ctx->net) | NFT_SET_ELEM_BUSY_MASK; err = set->ops->insert(ctx->net, set, &elem, &ext2); @@ -5404,7 +5424,7 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set, set->ops->remove(ctx->net, set, &elem); err_element_clash: kfree(trans); -err_trans: +err_elem_expr: if (obj) obj->use--;