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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 29FEBCF6C1F for ; Wed, 7 Jan 2026 09:33:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=SDqNWJIl9qHGi99geRD/Fpv3YwKNG7+YVHIuphn6+gE=; b=uBdBrwpYZS9P1cjmiAzn92CVca yh1KYBPwE0AkzH0SpFpNm0XlCTwrm+rFvWDXn6qwjSifkKf3NooEJ4MJOc4AamxhC0zZ7Bvkg9T+8 Nupxfk5UDhdnDYx04BMDChjO3ur31+wrly9mAhCXozeuw/Sz+PoM+ajtlklnL7+7l99VhF3PZXTIh xSRYjRWMUNmjorMyj8G3X9nrabpPvXZtWfpU7MjDb3HnVKykuwJbcMR29tohSAZ+wMmDCWBzCW0ed 3rQAYQUMX57kULJVes0+7ay324Q5BjjAN8sZSgYf24pEQOueBDdmXLn1yBygPLLoXh9RUr+zpk1/h a2qrzJXA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vdPut-0000000EXUz-3ty0; Wed, 07 Jan 2026 09:33:23 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vdPup-0000000EXSu-0WqJ for linux-arm-kernel@lists.infradead.org; Wed, 07 Jan 2026 09:33:23 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id CC77B41995; Wed, 7 Jan 2026 09:33:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2C6BFC4CEF7; Wed, 7 Jan 2026 09:33:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1767778398; bh=fcHHOaQzVIpjZZVBB6MbIxlqagyeNtB33hqQC3c9Nms=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ljRT/CaQGA0P+r1we4XG2EBhSLwD/70pG9mVCQocq4lTaLvK5dV/WoqudiHL/fUKo PyQDybJatQ+49AEZFiD/ZTHnR0ijLrHZnHtqG+15hiVn9Dls5C+bdKjMtLbfczLr/I ch9J7EX9AR7eV4IfAPjU5R0XdCUcdqx8zU4tKFCmsoExPDCn1FM5SneKSmE2CbzOE8 XindnCRTfJJ/ku7cWHmV8ssyVHv9qx8yJxQ/SbyXllDTjaRqZhvvwuQJ9OcOYtpQ0T krpBHPZw4ZJbSCgS0kQrUk9U62AcDAZv3K8yyn7uVHsOoWNeDAHiAeswkyxWAYVE8H I+DdHdAzkwYgA== From: Jiri Olsa To: Masami Hiramatsu , Steven Rostedt , Will Deacon Cc: Song Liu , Peter Zijlstra , bpf@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, x86@kernel.org, Yonghong Song , Song Liu , Andrii Nakryiko , Mark Rutland , Mahe Tardy Subject: [PATCH bpf-next 2/2] selftests/bpf: Add test for bpf_override_return helper Date: Wed, 7 Jan 2026 10:32:56 +0100 Message-ID: <20260107093256.54616-2-jolsa@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260107093256.54616-1-jolsa@kernel.org> References: <20260107093256.54616-1-jolsa@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260107_013321_972551_766561E8 X-CRM114-Status: GOOD ( 15.46 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org We do not actually test the bpf_override_return helper functionality itself at the moment, only the bpf program being able to attach it. Adding test that override prctl syscall return value on top of kprobe and kprobe.multi. Acked-by: Song Liu Signed-off-by: Jiri Olsa --- v1 changes: - added ack from Song - moved SYS_PREFIX to trace_helpers.h .../bpf/prog_tests/kprobe_multi_test.c | 44 +++++++++++++++++++ .../bpf/progs/kprobe_multi_override.c | 15 +++++++ tools/testing/selftests/bpf/trace_helpers.h | 12 +++++ 3 files changed, 71 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c index 6cfaa978bc9a..9caef222e528 100644 --- a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c +++ b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c @@ -1,4 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 +#include +#include #include #include "kprobe_multi.skel.h" #include "trace_helpers.h" @@ -540,6 +542,46 @@ static void test_attach_override(void) kprobe_multi_override__destroy(skel); } +static void test_override(void) +{ + struct kprobe_multi_override *skel = NULL; + int err; + + skel = kprobe_multi_override__open_and_load(); + if (!ASSERT_OK_PTR(skel, "kprobe_multi_empty__open_and_load")) + goto cleanup; + + skel->bss->pid = getpid(); + + /* no override */ + err = prctl(0xffff, 0); + ASSERT_EQ(err, -1, "err"); + + /* kprobe.multi override */ + skel->links.test_override = bpf_program__attach_kprobe_multi_opts(skel->progs.test_override, + SYS_PREFIX "sys_prctl", NULL); + if (!ASSERT_OK_PTR(skel->links.test_override, "bpf_program__attach_kprobe_multi_opts")) + goto cleanup; + + err = prctl(0xffff, 0); + ASSERT_EQ(err, 123, "err"); + + bpf_link__destroy(skel->links.test_override); + skel->links.test_override = NULL; + + /* kprobe override */ + skel->links.test_kprobe_override = bpf_program__attach_kprobe(skel->progs.test_kprobe_override, + false, SYS_PREFIX "sys_prctl"); + if (!ASSERT_OK_PTR(skel->links.test_kprobe_override, "bpf_program__attach_kprobe")) + goto cleanup; + + err = prctl(0xffff, 0); + ASSERT_EQ(err, 123, "err"); + +cleanup: + kprobe_multi_override__destroy(skel); +} + #ifdef __x86_64__ static void test_attach_write_ctx(void) { @@ -597,6 +639,8 @@ void test_kprobe_multi_test(void) test_attach_api_fails(); if (test__start_subtest("attach_override")) test_attach_override(); + if (test__start_subtest("override")) + test_override(); if (test__start_subtest("session")) test_session_skel_api(); if (test__start_subtest("session_cookie")) diff --git a/tools/testing/selftests/bpf/progs/kprobe_multi_override.c b/tools/testing/selftests/bpf/progs/kprobe_multi_override.c index 28f8487c9059..14f39fa6d515 100644 --- a/tools/testing/selftests/bpf/progs/kprobe_multi_override.c +++ b/tools/testing/selftests/bpf/progs/kprobe_multi_override.c @@ -5,9 +5,24 @@ char _license[] SEC("license") = "GPL"; +int pid = 0; + SEC("kprobe.multi") int test_override(struct pt_regs *ctx) { + if (bpf_get_current_pid_tgid() >> 32 != pid) + return 0; + + bpf_override_return(ctx, 123); + return 0; +} + +SEC("kprobe") +int test_kprobe_override(struct pt_regs *ctx) +{ + if (bpf_get_current_pid_tgid() >> 32 != pid) + return 0; + bpf_override_return(ctx, 123); return 0; } diff --git a/tools/testing/selftests/bpf/trace_helpers.h b/tools/testing/selftests/bpf/trace_helpers.h index 9437bdd4afa5..a5576b2dfc26 100644 --- a/tools/testing/selftests/bpf/trace_helpers.h +++ b/tools/testing/selftests/bpf/trace_helpers.h @@ -4,6 +4,18 @@ #include +#ifdef __x86_64__ +#define SYS_PREFIX "__x64_" +#elif defined(__s390x__) +#define SYS_PREFIX "__s390x_" +#elif defined(__aarch64__) +#define SYS_PREFIX "__arm64_" +#elif defined(__riscv) +#define SYS_PREFIX "__riscv_" +#else +#define SYS_PREFIX "" +#endif + #define __ALIGN_MASK(x, mask) (((x)+(mask))&~(mask)) #define ALIGN(x, a) __ALIGN_MASK(x, (typeof(x))(a)-1) -- 2.52.0