From patchwork Thu Jun 10 16:54:56 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pablo Neira Ayuso X-Patchwork-Id: 458322 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=-16.8 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=unavailable 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 422AFC47094 for ; Thu, 10 Jun 2021 16:55:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26528613F1 for ; Thu, 10 Jun 2021 16:55:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231597AbhFJQ5E (ORCPT ); Thu, 10 Jun 2021 12:57:04 -0400 Received: from mail.netfilter.org ([217.70.188.207]:34626 "EHLO mail.netfilter.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230370AbhFJQ5B (ORCPT ); Thu, 10 Jun 2021 12:57:01 -0400 Received: from localhost.localdomain (unknown [90.77.255.23]) by mail.netfilter.org (Postfix) with ESMTPSA id B75C16423C; Thu, 10 Jun 2021 18:53:49 +0200 (CEST) From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org, kuba@kernel.org Subject: [PATCH net 1/3] netfilter: nf_tables: initialize set before expression setup Date: Thu, 10 Jun 2021 18:54:56 +0200 Message-Id: <20210610165458.23071-2-pablo@netfilter.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210610165458.23071-1-pablo@netfilter.org> References: <20210610165458.23071-1-pablo@netfilter.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org nft_set_elem_expr_alloc() needs an initialized set if expression sets on the NFT_EXPR_GC flag. Move set fields initialization before expression setup. [4512935.019450] ================================================================== [4512935.019456] BUG: KASAN: null-ptr-deref in nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables] [4512935.019487] Read of size 8 at addr 0000000000000070 by task nft/23532 [4512935.019494] CPU: 1 PID: 23532 Comm: nft Not tainted 5.12.0-rc4+ #48 [...] [4512935.019502] Call Trace: [4512935.019505] dump_stack+0x89/0xb4 [4512935.019512] ? nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables] [4512935.019536] ? nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables] [4512935.019560] kasan_report.cold.12+0x5f/0xd8 [4512935.019566] ? nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables] [4512935.019590] nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables] [4512935.019615] nf_tables_newset+0xc7f/0x1460 [nf_tables] Reported-by: syzbot+ce96ca2b1d0b37c6422d@syzkaller.appspotmail.com Fixes: 65038428b2c6 ("netfilter: nf_tables: allow to specify stateful expression in set definition") Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 85 ++++++++++++++++++----------------- 1 file changed, 43 insertions(+), 42 deletions(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 72bc759179ef..bf4d6ec9fc55 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -4364,13 +4364,45 @@ static int nf_tables_newset(struct sk_buff *skb, const struct nfnl_info *info, err = nf_tables_set_alloc_name(&ctx, set, name); kfree(name); if (err < 0) - goto err_set_alloc_name; + goto err_set_name; + + udata = NULL; + if (udlen) { + udata = set->data + size; + nla_memcpy(udata, nla[NFTA_SET_USERDATA], udlen); + } + + INIT_LIST_HEAD(&set->bindings); + INIT_LIST_HEAD(&set->catchall_list); + set->table = table; + write_pnet(&set->net, net); + set->ops = ops; + set->ktype = ktype; + set->klen = desc.klen; + set->dtype = dtype; + set->objtype = objtype; + set->dlen = desc.dlen; + set->flags = flags; + set->size = desc.size; + set->policy = policy; + set->udlen = udlen; + set->udata = udata; + set->timeout = timeout; + set->gc_int = gc_int; + + set->field_count = desc.field_count; + for (i = 0; i < desc.field_count; i++) + set->field_len[i] = desc.field_len[i]; + + err = ops->init(set, &desc, nla); + if (err < 0) + goto err_set_init; if (nla[NFTA_SET_EXPR]) { expr = nft_set_elem_expr_alloc(&ctx, set, nla[NFTA_SET_EXPR]); if (IS_ERR(expr)) { err = PTR_ERR(expr); - goto err_set_alloc_name; + goto err_set_expr_alloc; } set->exprs[0] = expr; set->num_exprs++; @@ -4381,75 +4413,44 @@ static int nf_tables_newset(struct sk_buff *skb, const struct nfnl_info *info, if (!(flags & NFT_SET_EXPR)) { err = -EINVAL; - goto err_set_alloc_name; + goto err_set_expr_alloc; } i = 0; nla_for_each_nested(tmp, nla[NFTA_SET_EXPRESSIONS], left) { if (i == NFT_SET_EXPR_MAX) { err = -E2BIG; - goto err_set_init; + goto err_set_expr_alloc; } if (nla_type(tmp) != NFTA_LIST_ELEM) { err = -EINVAL; - goto err_set_init; + goto err_set_expr_alloc; } expr = nft_set_elem_expr_alloc(&ctx, set, tmp); if (IS_ERR(expr)) { err = PTR_ERR(expr); - goto err_set_init; + goto err_set_expr_alloc; } set->exprs[i++] = expr; set->num_exprs++; } } - udata = NULL; - if (udlen) { - udata = set->data + size; - nla_memcpy(udata, nla[NFTA_SET_USERDATA], udlen); - } - - INIT_LIST_HEAD(&set->bindings); - INIT_LIST_HEAD(&set->catchall_list); - set->table = table; - write_pnet(&set->net, net); - set->ops = ops; - set->ktype = ktype; - set->klen = desc.klen; - set->dtype = dtype; - set->objtype = objtype; - set->dlen = desc.dlen; - set->flags = flags; - set->size = desc.size; - set->policy = policy; - set->udlen = udlen; - set->udata = udata; - set->timeout = timeout; - set->gc_int = gc_int; set->handle = nf_tables_alloc_handle(table); - set->field_count = desc.field_count; - for (i = 0; i < desc.field_count; i++) - set->field_len[i] = desc.field_len[i]; - - err = ops->init(set, &desc, nla); - if (err < 0) - goto err_set_init; - err = nft_trans_set_add(&ctx, NFT_MSG_NEWSET, set); if (err < 0) - goto err_set_trans; + goto err_set_expr_alloc; list_add_tail_rcu(&set->list, &table->sets); table->use++; return 0; -err_set_trans: - ops->destroy(set); -err_set_init: +err_set_expr_alloc: for (i = 0; i < set->num_exprs; i++) nft_expr_destroy(&ctx, set->exprs[i]); -err_set_alloc_name: + + ops->destroy(set); +err_set_init: kfree(set->name); err_set_name: kvfree(set);