From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 17D72C43381 for ; Wed, 13 Mar 2019 19:26:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D4FB22075C for ; Wed, 13 Mar 2019 19:26:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552505213; bh=TY+zVZ/4klUEczISMX9gft6iMeeZS9G6MXrHEdH5kSg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=hnvYNfLycjeOmFUEuvwKN4Pf8CvYE3NAYyj6lpFNJn4XPG+vsJniOXQQ4Oo+EjS6p am2Xrvch8SlZT2CSXEKQW7Xx5AQWeIz4DiIAPLFaCuZm1BGhbP9ln4pW0VBy1w6Du9 s/tcgB/2baQbxkVrtKxsAJ0nwyFsuuVHnQMMD7D4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728343AbfCMT0w (ORCPT ); Wed, 13 Mar 2019 15:26:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:45044 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728272AbfCMTOn (ORCPT ); Wed, 13 Mar 2019 15:14:43 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CD2B82171F; Wed, 13 Mar 2019 19:14:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552504482; bh=TY+zVZ/4klUEczISMX9gft6iMeeZS9G6MXrHEdH5kSg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nzHiqfplw01PJFIViHG6j0zx8QA7RkDuoIZZZdJ+bzW2qNxCJR5t415i9E5IwDm44 /un48Jhzo9dSJHD7GWus5egaTwBWX/WUeLwAfJVFkGWjw35ij9rlpTCfcw2h8vkJqN aYkaQSVkNzPVYrKyGAK+D40LhJcgdZuFBv6zkAek= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Alban Crequy , Craig Gallek , Daniel Borkmann , Sasha Levin , netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 39/48] bpf, lpm: fix lookup bug in map_delete_elem Date: Wed, 13 Mar 2019 15:12:41 -0400 Message-Id: <20190313191250.158955-39-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190313191250.158955-1-sashal@kernel.org> References: <20190313191250.158955-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alban Crequy [ Upstream commit 7c0cdf0b3940f63d9777c3fcf250a2f83859ca54 ] trie_delete_elem() was deleting an entry even though it was not matching if the prefixlen was correct. This patch adds a check on matchlen. Reproducer: $ sudo bpftool map create /sys/fs/bpf/mylpm type lpm_trie key 8 value 1 entries 128 name mylpm flags 1 $ sudo bpftool map update pinned /sys/fs/bpf/mylpm key hex 10 00 00 00 aa bb cc dd value hex 01 $ sudo bpftool map dump pinned /sys/fs/bpf/mylpm key: 10 00 00 00 aa bb cc dd value: 01 Found 1 element $ sudo bpftool map delete pinned /sys/fs/bpf/mylpm key hex 10 00 00 00 ff ff ff ff $ echo $? 0 $ sudo bpftool map dump pinned /sys/fs/bpf/mylpm Found 0 elements A similar reproducer is added in the selftests. Without the patch: $ sudo ./tools/testing/selftests/bpf/test_lpm_map test_lpm_map: test_lpm_map.c:485: test_lpm_delete: Assertion `bpf_map_delete_elem(map_fd, key) == -1 && errno == ENOENT' failed. Aborted With the patch: test_lpm_map runs without errors. Fixes: e454cf595853 ("bpf: Implement map_delete_elem for BPF_MAP_TYPE_LPM_TRIE") Cc: Craig Gallek Signed-off-by: Alban Crequy Acked-by: Craig Gallek Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin --- kernel/bpf/lpm_trie.c | 1 + tools/testing/selftests/bpf/test_lpm_map.c | 10 ++++++++++ 2 files changed, 11 insertions(+) diff --git a/kernel/bpf/lpm_trie.c b/kernel/bpf/lpm_trie.c index 9058317ba9de..4f3138e6ecb2 100644 --- a/kernel/bpf/lpm_trie.c +++ b/kernel/bpf/lpm_trie.c @@ -432,6 +432,7 @@ static int trie_delete_elem(struct bpf_map *map, void *_key) } if (!node || node->prefixlen != key->prefixlen || + node->prefixlen != matchlen || (node->flags & LPM_TREE_NODE_FLAG_IM)) { ret = -ENOENT; goto out; diff --git a/tools/testing/selftests/bpf/test_lpm_map.c b/tools/testing/selftests/bpf/test_lpm_map.c index 147e34cfceb7..02d7c871862a 100644 --- a/tools/testing/selftests/bpf/test_lpm_map.c +++ b/tools/testing/selftests/bpf/test_lpm_map.c @@ -474,6 +474,16 @@ static void test_lpm_delete(void) assert(bpf_map_lookup_elem(map_fd, key, &value) == -1 && errno == ENOENT); + key->prefixlen = 30; // unused prefix so far + inet_pton(AF_INET, "192.255.0.0", key->data); + assert(bpf_map_delete_elem(map_fd, key) == -1 && + errno == ENOENT); + + key->prefixlen = 16; // same prefix as the root node + inet_pton(AF_INET, "192.255.0.0", key->data); + assert(bpf_map_delete_elem(map_fd, key) == -1 && + errno == ENOENT); + /* assert initial lookup */ key->prefixlen = 32; inet_pton(AF_INET, "192.168.0.1", key->data); -- 2.19.1