From patchwork Sat Oct 26 05:04:58 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Byeonguk Jeong X-Patchwork-Id: 13852063 X-Patchwork-Delegate: bpf@iogearbox.net Received: from mail-pg1-f171.google.com (mail-pg1-f171.google.com [209.85.215.171]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A457F3398B; Sat, 26 Oct 2024 05:05:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.171 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729919106; cv=none; b=oe7qJ38DLUhKygO6T8fL+rhPcKAZnDmD2S/LYOPSq6NyrFD4A3FBB4qVVvib3IGTzgAVjMHalQKZGS3y69fnTNBYV3W682797f0bicsKOI/ZFQmojLL1a0C4aRsmVNEBxoW2UiHwMqmh/tRlIV07Em+7H3oKyeEzgFo0c1vAWCo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729919106; c=relaxed/simple; bh=83BNDMZYHh7THxcOT6EMx1nYZHH4/+7P9EvKGPKbppA=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=MRIO8/I73iML8oXV7as3z5tlcXzkHI2cvFfMY/3wOykAzPndAiGKgGcWIOu0Hrxj1RMYWjC0oXr0JGKeqtdJuyrNzlavfX1tAhmezd2XPNKTxZFQrG1dFHJjkRFWpsURbbaNrCGlYeXyndHDBYAwjgKuqAmPDCsAVlXA1jlzwhw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=UrBjgNnu; arc=none smtp.client-ip=209.85.215.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="UrBjgNnu" Received: by mail-pg1-f171.google.com with SMTP id 41be03b00d2f7-7e9e38dd5f1so2059182a12.0; Fri, 25 Oct 2024 22:05:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1729919104; x=1730523904; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:message-id:subject:cc :to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=k1gFZ09BPOfzHvjNYWOqC2145s1yc+PKpA6ny3/E+XQ=; b=UrBjgNnupUF5Nr00nSph0OXvxbglevjI8G0PFhNvM6Sx0ElpLkg+E/SHAz4Tq5wjxE Lz/ZCcc+RhgAfqvuPJ2T8/g1OJ2cPNtf8BncmY7qE142hJ4fZ2yMxr+ee04yFEXAWlxF hrJhnDhr7mhC17mkufnZ54AMIVymne/ncCHGCkE3H+uHqELaCXDeOe/LqNn5HWJ3oEl1 9aNMdKH8PFkdWpW8DC+hD1ukgBfK4vi7Z+q/NZ54RWP/4NbzzgIn8nz42SVquOAqWkIY gX/1XM6tStB8OEeHnDlidanQTkJyJIov39c8KVLQI7hAWB3G+Wioa3IP5IYimWRg/7OQ tX7Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1729919104; x=1730523904; h=in-reply-to:content-disposition:mime-version:message-id:subject:cc :to:from:date:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=k1gFZ09BPOfzHvjNYWOqC2145s1yc+PKpA6ny3/E+XQ=; b=q8S7QJzVblMYc+ZYU01YcudIRfDVsuwnIE9z0xiHJCacKrKmH3rNW5dIN38Poftg5+ v0/GTWcd9QoCrYU3e6LdsUIK99UWvtcXqNl0ONXQWp9Qp38NzTbWvdAoV+WhiLuzYwfO ccS34Jew2PIUsUU3NNkfAarowEVIys0VQu9tHCpHPEBTLETx1RgW5XXxhw6UqsjrAcZd fwJzAqcjQxw7N/EjMMh1i4jOlZ9yoAtDU+qWYaT2PaH94d2ORw7cXUGh5zRSR8YTKvco eGCfvbnm0B2zHwj4rrePCj4Mel1JFAgI+S5+2P/+IEKXYWNVJGVSermnvMiS1jSHs33G IwAA== X-Forwarded-Encrypted: i=1; AJvYcCU4w6eQUqUzqfh93L89BIXuUYHn8aQBLo51449Q+gL4BQTgCYyrsN/p4uc4Bu7xnR6ft9Q=@vger.kernel.org X-Gm-Message-State: AOJu0YwukJi3KUX0wuHoWGrYEZtyunIEivmX8F6xwumOoVeaXYYzPbfK wvdQOjpZVY+g75AguPV9GeSb6HO/1exlBQ8tvVUMpk5BK5p06Fa5 X-Google-Smtp-Source: AGHT+IFOBqIZdLWrqdbJ8ern5k5129qAspVS4COwJfcywYv6snpMH/jgCI24HLI89bTyzo5kRfz2Kw== X-Received: by 2002:a05:6a21:4781:b0:1d8:f5e1:6b30 with SMTP id adf61e73a8af0-1d9a850ab78mr2139652637.48.1729919103894; Fri, 25 Oct 2024 22:05:03 -0700 (PDT) Received: from localhost.localdomain ([210.205.14.5]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-72057a3c20fsm1974695b3a.200.2024.10.25.22.05.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 25 Oct 2024 22:05:03 -0700 (PDT) Date: Sat, 26 Oct 2024 14:04:58 +0900 From: Byeonguk Jeong To: Toke =?utf-8?q?H=C3=B8iland-J=C3=B8rgensen?= , Alexei Starovoitov , Daniel Borkmann , Hou Tao , Yonghong Song Cc: linux-kernel@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH v2 bpf 2/2] selftests/bpf: Add test for trie_get_next_key() Message-ID: Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-Patchwork-Delegate: bpf@iogearbox.net Add a test for out-of-bounds write in trie_get_next_key() when a full path from root to leaf exists and bpf_map_get_next_key() is called with the leaf node. It may crashes the kernel on failure, so please run in a VM. Signed-off-by: Byeonguk Jeong --- v1 -> v2: - Fixed a build error. - Removed unnecessary comments about crash-on-failure warning. - Fix a variable to be initialized before using it. --- .../bpf/map_tests/lpm_trie_map_get_next_key.c | 109 ++++++++++++++++++ 1 file changed, 109 insertions(+) create mode 100644 tools/testing/selftests/bpf/map_tests/lpm_trie_map_get_next_key.c diff --git a/tools/testing/selftests/bpf/map_tests/lpm_trie_map_get_next_key.c b/tools/testing/selftests/bpf/map_tests/lpm_trie_map_get_next_key.c new file mode 100644 index 000000000000..0ba015686492 --- /dev/null +++ b/tools/testing/selftests/bpf/map_tests/lpm_trie_map_get_next_key.c @@ -0,0 +1,109 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include + +struct test_lpm_key { + __u32 prefix; + __u32 data; +}; + +struct get_next_key_ctx { + struct test_lpm_key key; + bool start; + bool stop; + int map_fd; + int loop; +}; + +static void *get_next_key_fn(void *arg) +{ + struct get_next_key_ctx *ctx = arg; + struct test_lpm_key next_key; + int i = 0; + + while (!ctx->start) + usleep(1); + + while (!ctx->stop && i++ < ctx->loop) + bpf_map_get_next_key(ctx->map_fd, &ctx->key, &next_key); + + return NULL; +} + +static void abort_get_next_key(struct get_next_key_ctx *ctx, pthread_t *tids, + unsigned int nr) +{ + unsigned int i; + + ctx->stop = true; + ctx->start = true; + for (i = 0; i < nr; i++) + pthread_join(tids[i], NULL); +} + +/* This test aims to prevent regression of future. As long as the kernel does + * not panic, it is considered as success. + */ +void test_lpm_trie_map_get_next_key(void) +{ +#define MAX_NR_THREADS 8 + LIBBPF_OPTS(bpf_map_create_opts, create_opts, + .map_flags = BPF_F_NO_PREALLOC); + struct test_lpm_key key = {}; + __u32 val = 0; + int map_fd; + const __u32 max_prefixlen = 8 * (sizeof(key) - sizeof(key.prefix)); + const __u32 max_entries = max_prefixlen + 1; + unsigned int i, nr = MAX_NR_THREADS, loop = 65536; + pthread_t tids[MAX_NR_THREADS]; + struct get_next_key_ctx ctx; + int err; + + map_fd = bpf_map_create(BPF_MAP_TYPE_LPM_TRIE, "lpm_trie_map", + sizeof(struct test_lpm_key), sizeof(__u32), + max_entries, &create_opts); + CHECK(map_fd == -1, "bpf_map_create()", "error:%s\n", + strerror(errno)); + + for (i = 0; i <= max_prefixlen; i++) { + key.prefix = i; + err = bpf_map_update_elem(map_fd, &key, &val, BPF_ANY); + CHECK(err, "bpf_map_update_elem()", "error:%s\n", + strerror(errno)); + } + + ctx.start = false; + ctx.stop = false; + ctx.map_fd = map_fd; + ctx.loop = loop; + memcpy(&ctx.key, &key, sizeof(key)); + + for (i = 0; i < nr; i++) { + err = pthread_create(&tids[i], NULL, get_next_key_fn, &ctx); + if (err) { + abort_get_next_key(&ctx, tids, i); + CHECK(err, "pthread_create", "error %d\n", err); + } + } + + ctx.start = true; + for (i = 0; i < nr; i++) + pthread_join(tids[i], NULL); + + printf("%s:PASS\n", __func__); + + close(map_fd); +}