From patchwork Tue Jan 28 22:43:52 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jordan Rome X-Patchwork-Id: 13953325 X-Patchwork-Delegate: bpf@iogearbox.net Received: from mout.perfora.net (mout.perfora.net [74.208.4.194]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DF0591C3BF7 for ; Tue, 28 Jan 2025 22:44:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.208.4.194 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738104267; cv=none; b=kChGoQisIBzp05uNz5EhxK520pV/k8Ial82AKyCIUHP72P7aGxZkY8iQeE0fx0lyv8+T3Q4PqU5NcgUUiLSSXH/by25gVhjqe/xEaSSNsCG2JCr07hMj1QRbC9qfJiH33UN+xDg/y+CvwK+yNnOtmfV8BF+TE9Y/d/BGaflTOdg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738104267; c=relaxed/simple; bh=sC2j8xRGHe7nr+QNZ5ZANfcvHGfTRLLs3oKofC73OZw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=e9xY68OB7NqtsXOfuRtgax3isuDizCY0ZJOFEmY8abX9tpu4F2dg2dE9pCS4FRDf2QKPhXk3E4wOl9vzljtaoT5LC036BXdF2vqCqYC+dICeMZO1DPjGD87a4R1VN80BBpJH5VHYj1Q8OO1qHpFKzJIUHiaWtJfazf2dq4Hm7gg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=jordanrome.com; spf=pass smtp.mailfrom=jordanrome.com; dkim=pass (2048-bit key) header.d=jordanrome.com header.i=linux@jordanrome.com header.b=2tRjXSHe; arc=none smtp.client-ip=74.208.4.194 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=jordanrome.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=jordanrome.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=jordanrome.com header.i=linux@jordanrome.com header.b="2tRjXSHe" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=jordanrome.com; s=s1-ionos; t=1738104255; x=1738709055; i=linux@jordanrome.com; bh=LhJJH5WuMX5aq6LX3M5eXAA/nYkW+PydFm8hbRxet3Y=; h=X-UI-Sender-Class:From:To:Cc:Subject:Date:Message-ID:In-Reply-To: References:MIME-Version:Content-Transfer-Encoding:cc: content-transfer-encoding:content-type:date:from:message-id: mime-version:reply-to:subject:to; b=2tRjXSHe/cXn1FoqIkguxSxTIWSxQYsaSCPdxkI42RSPpQt2UlWePk1il7Xa6VyB XrAVJVUJn0P2FMPF4YulA3dTrrUI98UlY8zh+SD632nPzq1z2p2KWl0qMZUoIHFkY K2/pOsaIYuf/2env6m/UV83If0p5lhzfGCpBgfbv1wxfHrlaOWX5xwrXCDdIQy2Bw dvAf0Xa/oKS+kIzT1lmkNDQC53fG7zwnxYXwrqUXx3vg/BfKckYkFMW5lOpDZ2CXQ fLYuQo36nBiuCBVjtg6TnW++NQ+Y4+Ta0T75PJ6RvjTK735wi94lMGTd8XfNULd7C G9iL4WKeoB1j/zRYzw== X-UI-Sender-Class: 55c96926-9e95-11ee-ae09-1f7a4046a0f6 Received: from localhost ([69.171.251.3]) by mrelay.perfora.net (mreueus004 [74.208.5.2]) with ESMTPSA (Nemesis) id 1MwxJ1-1tF1lc0Dhz-00tyiV; Tue, 28 Jan 2025 23:44:15 +0100 From: Jordan Rome To: bpf@vger.kernel.org Cc: linux-mm@kvack.org, Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Kernel Team , Andrew Morton , Shakeel Butt , Alexander Potapenko Subject: [bpf-next v6 3/3] selftests/bpf: Add tests for bpf_copy_from_user_task_str Date: Tue, 28 Jan 2025 14:43:52 -0800 Message-ID: <20250128224352.3808460-3-linux@jordanrome.com> X-Mailer: git-send-email 2.43.5 In-Reply-To: <20250128224352.3808460-1-linux@jordanrome.com> References: <20250128224352.3808460-1-linux@jordanrome.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Provags-ID: V03:K1:dUpyW8ZQI4xCv3r6SWnn1cP0igwa1BlRWYz1XV0OhYgqhhyXbq4 2/ZOwp/r0QLRCb8dTC27YKV12g8V4tHfTxApeitjEOKpVG6/rm9vvlDbR0Ga56y+9MIjDDQ VMjo+x/UdzAZNmt+tXryeel4uAAgiq1Hss6vh5hV8WvyVGETCg5dv/GJimVPvqHNUQwk/Lb jPobii2DRd1EQ4SpTbloA== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:BBG0znHmojc=;jyOkfJqp77N3aFhAWLMgPFmcmEo jOor2fIc/IMLOQUabPQvbCE9fM/ZQp1lsMoEzplfjJkMGjv/On3Xz9SoR1KqyZ4so2NiuY1ng uiAMuRDXhYtE/2QVPj1pbWYVnxDKSOk3YFc7CKBN3YaapwLquS2kh8x7yqJaNDynsLyEy6XSt YnAyEB41gx2wK5wDLpvO4rKRURbTP59yZVWzdrgYJYL3N8Ka1vTImqwHYX7qfnFtraiAP/lA5 3K6+wSzv/SnJP1UO1cE52OPo154CORBEqEr+yqbDs0rlWj6Gh3Bzc+ItkSwc+iefN/sz1l1UH SPH2sNR+fcK6MSFs+T7SCPiUPuqAP2xefPwroNi3T3p1lUbfousbjvadE4tT2ZCSM+lEmhl4x micd13WC/cvOJWoAbJmR5jpdLMLW61clY4jcBt8X5z9nMXTNpDeo6Dogf7v1QP0ljYxtKw0sC H+X57bGhuW7nYKerb3UK1Koe8EEYarOXHHCVebRMKFCeS+tort/uvabwNBmtR/fILKEpcGmfp k9geUhZdkUJM7bPMQYXPSXjkMoTR04A1wRoPptKE8dHx9tA8XhzJzABwp44ioCCVMG6KnYzry N0P2ZnNHd8X9erUAm6W2+GojwYXSHhT341Sq/TLusIyjFbK2o0Q3I+DPlPSEZyqbPSgXle15t JVo2gZLXtod5WV9h/iV5e5TD7Ir7RfWFM/ouuXNwdZcpEPIUbT25AY/XoPRHdC4MZr5IxQdGv oXiGb2zQVhLqcMaFmZJqFYaCkbozJ/spRp/kC42VzId8uIbBsVY3wXxuT4iYwZmN3zldsinRG eZ4IgpxKszf9v6QnVNq/77R4PFs0cD9XcfOocuLB27UYpZu9lwcSCV95/8QmEIXDa8QsPXjeB VAx9awSCslCsxUrUSs3jtP/nYzlBxPMvAWBAi61K3uJVrrVDde1VC/BkTqCt2g0z/Mx3dy4Gx PsauebZ2ziTSjcvKm32kGQG6Wc9Il6I1YW+OSxlAvDvGhkgTHmz/83wCK9GmBrMwZmyHP7sXT X4uhjwjjxk3UuXwCDv0mE+gWKIJ1Rn5M/2xlG+bbIoD4/RrzSFQ06U4ZKwEiVmsNBLBt9kGkw OiB0E3WePbhUv6iCp8ZkA/b3aCY4aWaKTL5dBr0AAu5kF/MjqGKQ== X-Patchwork-Delegate: bpf@iogearbox.net This adds tests for both the happy path and the error path (with and without the BPF_F_PAD_ZEROS flag). Signed-off-by: Jordan Rome --- .../selftests/bpf/prog_tests/bpf_iter.c | 68 +++++++++++ .../selftests/bpf/prog_tests/read_vsyscall.c | 1 + .../selftests/bpf/progs/bpf_iter_tasks.c | 110 ++++++++++++++++++ .../selftests/bpf/progs/read_vsyscall.c | 11 +- 4 files changed, 188 insertions(+), 2 deletions(-) -- 2.43.5 diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c index 6f1bfacd7375..add4a18c33bd 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c @@ -323,19 +323,87 @@ static void test_task_pidfd(void) static void test_task_sleepable(void) { struct bpf_iter_tasks *skel; + int pid, status, err, data_pipe[2], finish_pipe[2], c; + char *test_data = NULL; + char *test_data_long = NULL; + char *data[2]; + + if (!ASSERT_OK(pipe(data_pipe), "data_pipe") || + !ASSERT_OK(pipe(finish_pipe), "finish_pipe")) + return; skel = bpf_iter_tasks__open_and_load(); if (!ASSERT_OK_PTR(skel, "bpf_iter_tasks__open_and_load")) return; + pid = fork(); + if (!ASSERT_GE(pid, 0, "fork")) + return; + + if (pid == 0) { + /* child */ + close(data_pipe[0]); + close(finish_pipe[1]); + + test_data = malloc(sizeof(char) * 10); + strncpy(test_data, "test_data", 10); + test_data[9] = '\0'; + + test_data_long = malloc(sizeof(char) * 5000); + for (int i = 0; i < 5000; ++i) { + if (i % 2 == 0) + test_data_long[i] = 'b'; + else + test_data_long[i] = 'a'; + } + test_data_long[4999] = '\0'; + + data[0] = test_data; + data[1] = test_data_long; + + write(data_pipe[1], &data, sizeof(data)); + + /* keep child alive until after the test */ + err = read(finish_pipe[0], &c, 1); + if (err != 1) + exit(-1); + + close(data_pipe[1]); + close(finish_pipe[0]); + _exit(0); + } + + /* parent */ + close(data_pipe[1]); + close(finish_pipe[0]); + + err = read(data_pipe[0], &data, sizeof(data)); + ASSERT_EQ(err, sizeof(data), "read_check"); + + skel->bss->user_ptr = data[0]; + skel->bss->user_ptr_long = data[1]; + skel->bss->pid = pid; + do_dummy_read(skel->progs.dump_task_sleepable); ASSERT_GT(skel->bss->num_expected_failure_copy_from_user_task, 0, "num_expected_failure_copy_from_user_task"); ASSERT_GT(skel->bss->num_success_copy_from_user_task, 0, "num_success_copy_from_user_task"); + ASSERT_GT(skel->bss->num_expected_failure_copy_from_user_task_str, 0, + "num_expected_failure_copy_from_user_task_str"); + ASSERT_GT(skel->bss->num_success_copy_from_user_task_str, 0, + "num_success_copy_from_user_task_str"); bpf_iter_tasks__destroy(skel); + + write(finish_pipe[1], &c, 1); + err = waitpid(pid, &status, 0); + ASSERT_EQ(err, pid, "waitpid"); + ASSERT_EQ(status, 0, "zero_child_exit"); + + close(data_pipe[0]); + close(finish_pipe[1]); } static void test_task_stack(void) diff --git a/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c b/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c index c7b9ba8b1d06..a8d1eaa67020 100644 --- a/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c +++ b/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c @@ -24,6 +24,7 @@ struct read_ret_desc { { .name = "copy_from_user", .ret = -EFAULT }, { .name = "copy_from_user_task", .ret = -EFAULT }, { .name = "copy_from_user_str", .ret = -EFAULT }, + { .name = "copy_from_user_task_str", .ret = -EFAULT }, }; void test_read_vsyscall(void) diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_tasks.c b/tools/testing/selftests/bpf/progs/bpf_iter_tasks.c index bc10c4e4b4fa..966ee5a7b066 100644 --- a/tools/testing/selftests/bpf/progs/bpf_iter_tasks.c +++ b/tools/testing/selftests/bpf/progs/bpf_iter_tasks.c @@ -9,6 +9,13 @@ char _license[] SEC("license") = "GPL"; uint32_t tid = 0; int num_unknown_tid = 0; int num_known_tid = 0; +void *user_ptr = 0; +void *user_ptr_long = 0; +uint32_t pid = 0; + +static char big_str1[5000]; +static char big_str2[5005]; +static char big_str3[4996]; SEC("iter/task") int dump_task(struct bpf_iter__task *ctx) @@ -35,7 +42,9 @@ int dump_task(struct bpf_iter__task *ctx) } int num_expected_failure_copy_from_user_task = 0; +int num_expected_failure_copy_from_user_task_str = 0; int num_success_copy_from_user_task = 0; +int num_success_copy_from_user_task_str = 0; SEC("iter.s/task") int dump_task_sleepable(struct bpf_iter__task *ctx) @@ -44,6 +53,9 @@ int dump_task_sleepable(struct bpf_iter__task *ctx) struct task_struct *task = ctx->task; static const char info[] = " === END ==="; struct pt_regs *regs; + char task_str1[10] = "aaaaaaaaaa"; + char task_str2[10], task_str3[10]; + char task_str4[20] = "aaaaaaaaaaaaaaaaaaaa"; void *ptr; uint32_t user_data = 0; int ret; @@ -78,8 +90,106 @@ int dump_task_sleepable(struct bpf_iter__task *ctx) BPF_SEQ_PRINTF(seq, "%s\n", info); return 0; } + ++num_success_copy_from_user_task; + /* Read an invalid pointer and ensure we get an error */ + ptr = NULL; + ret = bpf_copy_from_user_task_str((char *)task_str1, sizeof(task_str1), ptr, task, 0); + if (ret >= 0 || task_str1[9] != 'a' || task_str1[0] != '\0') { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* Read an invalid pointer and ensure we get error with pad zeros flag */ + ptr = NULL; + ret = bpf_copy_from_user_task_str((char *)task_str1, sizeof(task_str1), + ptr, task, BPF_F_PAD_ZEROS); + if (ret >= 0 || task_str1[9] != '\0' || task_str1[0] != '\0') { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + ++num_expected_failure_copy_from_user_task_str; + + /* Same length as the string */ + ret = bpf_copy_from_user_task_str((char *)task_str2, 10, user_ptr, task, 0); + /* only need to do the task pid check once */ + if (bpf_strncmp(task_str2, 10, "test_data\0") != 0 || ret != 10 || task->tgid != pid) { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* Shorter length than the string */ + ret = bpf_copy_from_user_task_str((char *)task_str3, 2, user_ptr, task, 0); + if (bpf_strncmp(task_str3, 2, "t\0") != 0 || ret != 2) { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* Longer length than the string */ + ret = bpf_copy_from_user_task_str((char *)task_str4, 20, user_ptr, task, 0); + if (bpf_strncmp(task_str4, 10, "test_data\0") != 0 || ret != 10 + || task_str4[sizeof(task_str4) - 1] != 'a') { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* Longer length than the string with pad zeros flag */ + ret = bpf_copy_from_user_task_str((char *)task_str4, 20, user_ptr, task, BPF_F_PAD_ZEROS); + if (bpf_strncmp(task_str4, 10, "test_data\0") != 0 || ret != 10 + || task_str4[sizeof(task_str4) - 1] != '\0') { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* Longer length than the string past a page boundary */ + ret = bpf_copy_from_user_task_str(big_str1, 5000, user_ptr, task, 0); + if (bpf_strncmp(big_str1, 10, "test_data\0") != 0 || ret != 10) { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* String that crosses a page boundary */ + ret = bpf_copy_from_user_task_str(big_str1, 5000, user_ptr_long, task, BPF_F_PAD_ZEROS); + if (bpf_strncmp(big_str1, 4, "baba") != 0 || ret != 5000 + || bpf_strncmp(big_str1 + 4996, 4, "bab\0") != 0) { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + for (int i = 0; i < 4999; ++i) { + if (i % 2 == 0) { + if (big_str1[i] != 'b') { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + } else { + if (big_str1[i] != 'a') { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + } + } + + /* Longer length than the string that crosses a page boundary */ + ret = bpf_copy_from_user_task_str(big_str2, 5005, user_ptr_long, task, BPF_F_PAD_ZEROS); + if (bpf_strncmp(big_str2, 4, "baba") != 0 || ret != 5000 + || bpf_strncmp(big_str2 + 4996, 5, "bab\0\0") != 0) { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + /* Shorter length than the string that crosses a page boundary */ + ret = bpf_copy_from_user_task_str(big_str3, 4996, user_ptr_long, task, 0); + if (bpf_strncmp(big_str3, 4, "baba") != 0 || ret != 4996 + || bpf_strncmp(big_str3 + 4992, 4, "bab\0") != 0) { + BPF_SEQ_PRINTF(seq, "%s\n", info); + return 0; + } + + ++num_success_copy_from_user_task_str; + if (ctx->meta->seq_num == 0) BPF_SEQ_PRINTF(seq, " tgid gid data\n"); diff --git a/tools/testing/selftests/bpf/progs/read_vsyscall.c b/tools/testing/selftests/bpf/progs/read_vsyscall.c index 39ebef430059..395591374d4f 100644 --- a/tools/testing/selftests/bpf/progs/read_vsyscall.c +++ b/tools/testing/selftests/bpf/progs/read_vsyscall.c @@ -8,14 +8,16 @@ int target_pid = 0; void *user_ptr = 0; -int read_ret[9]; +int read_ret[10]; char _license[] SEC("license") = "GPL"; /* - * This is the only kfunc, the others are helpers + * These are the kfuncs, the others are helpers */ int bpf_copy_from_user_str(void *dst, u32, const void *, u64) __weak __ksym; +int bpf_copy_from_user_task_str(void *dst, u32, const void *, + struct task_struct *, u64) __weak __ksym; SEC("fentry/" SYS_PREFIX "sys_nanosleep") int do_probe_read(void *ctx) @@ -47,6 +49,11 @@ int do_copy_from_user(void *ctx) read_ret[7] = bpf_copy_from_user_task(buf, sizeof(buf), user_ptr, bpf_get_current_task_btf(), 0); read_ret[8] = bpf_copy_from_user_str((char *)buf, sizeof(buf), user_ptr, 0); + read_ret[9] = bpf_copy_from_user_task_str((char *)buf, + sizeof(buf), + user_ptr, + bpf_get_current_task_btf(), + 0); return 0; }