From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 3A1602194A8; Wed, 25 Sep 2024 12:13:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727266408; cv=none; b=P+AGpUidHSyDiSVCHJTO1QNfakA3eAYhn1XL5YqMyb04s9+aUCKFAdcAo1Gt/hB7Iyoq7Dutim+1UkAFcgurg4IEs//i7t8sxyD92/f18sAca6hT1UhwwQyGPp80rDO/MybRQJLkDHUPW7ilnu8EZtH5hbUv7j2ud/4PY+49B5U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727266408; c=relaxed/simple; bh=LrCOcNgGPitG5crkhX9bq4DBpSXYwgiiKFJA3JrJJCI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VxqjYMKc2xO76/zEdAVba4uWqj6U3vU3vNVkMWBuuKfxSm0KaAzCy1e2OA5o1YWLvjnvW7xreqwUca+UQpZ25Q1O0zgY25ojyPg0apDseBGqxXv7QLNfxNji3M02OMxgJzQNKbk+2UUj/5o86AiK1SjUFioIg9G5P1yLv4aiToM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=fail (0-bit key) header.d=kernel.org header.i=@kernel.org header.b=ugK2Rszc reason="key not found in DNS"; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=kernel.org header.i=@kernel.org header.b="ugK2Rszc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7F591C4CEC3; Wed, 25 Sep 2024 12:13:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1727266408; bh=LrCOcNgGPitG5crkhX9bq4DBpSXYwgiiKFJA3JrJJCI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ugK2RszcsEfHwDOFcf/qV8Z7Od8qZTgf31yNsjjVyvPt5QsZT2XZ5w94YfJQByuu7 ofLJXXLPUJXrOxfagE42W7i9w+3Hs5UiLsoyd+GV4Eo3OCBDFx2rESRwUX02b8Cxes p6blDDD8YrOYcH47tciN7squloF1DEuUYEGqOOHsjJ444ABibf24fE2++/KiCYqUjM XRqWTvEeuYTCkky3Yn+aXfjmD/mvH/gFnMXQxe7ghiydVWdUkYFHjqupLKQcFF8m23 4Yd4z5gj+Lc+KM3JCiJBXx06UC74vqZHcndiGjGIZgx7icK3n/hU0U9eSgeBWVUOdV FuZs0vcrcQCfw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: James Clark , Al Grant , Will Deacon , Sasha Levin , mark.rutland@arm.com, peterz@infradead.org, mingo@redhat.com, acme@kernel.org, namhyung@kernel.org, linux-arm-kernel@lists.infradead.org, linux-perf-users@vger.kernel.org Subject: [PATCH AUTOSEL 6.6 049/139] drivers/perf: arm_spe: Use perf_allow_kernel() for permissions Date: Wed, 25 Sep 2024 08:07:49 -0400 Message-ID: <20240925121137.1307574-49-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240925121137.1307574-1-sashal@kernel.org> References: <20240925121137.1307574-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.6.52 Content-Transfer-Encoding: 8bit From: James Clark [ Upstream commit 5e9629d0ae977d6f6916d7e519724804e95f0b07 ] Use perf_allow_kernel() for 'pa_enable' (physical addresses), 'pct_enable' (physical timestamps) and context IDs. This means that perf_event_paranoid is now taken into account and LSM hooks can be used, which is more consistent with other perf_event_open calls. For example PERF_SAMPLE_PHYS_ADDR uses perf_allow_kernel() rather than just perfmon_capable(). This also indirectly fixes the following error message which is misleading because perf_event_paranoid is not taken into account by perfmon_capable(): $ perf record -e arm_spe/pa_enable/ Error: Access to performance monitoring and observability operations is limited. Consider adjusting /proc/sys/kernel/perf_event_paranoid setting ... Suggested-by: Al Grant Signed-off-by: James Clark Link: https://lore.kernel.org/r/20240827145113.1224604-1-james.clark@linaro.org Link: https://lore.kernel.org/all/20240807120039.GD37996@noisy.programming.kicks-ass.net/ Signed-off-by: Will Deacon Signed-off-by: Sasha Levin --- drivers/perf/arm_spe_pmu.c | 9 ++++----- include/linux/perf_event.h | 8 +------- kernel/events/core.c | 9 +++++++++ 3 files changed, 14 insertions(+), 12 deletions(-) diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c index d2b0cbf0e0c41..2bec2e3af0bd6 100644 --- a/drivers/perf/arm_spe_pmu.c +++ b/drivers/perf/arm_spe_pmu.c @@ -41,7 +41,7 @@ /* * Cache if the event is allowed to trace Context information. - * This allows us to perform the check, i.e, perfmon_capable(), + * This allows us to perform the check, i.e, perf_allow_kernel(), * in the context of the event owner, once, during the event_init(). */ #define SPE_PMU_HW_FLAGS_CX 0x00001 @@ -50,7 +50,7 @@ static_assert((PERF_EVENT_FLAG_ARCH & SPE_PMU_HW_FLAGS_CX) == SPE_PMU_HW_FLAGS_C static void set_spe_event_has_cx(struct perf_event *event) { - if (IS_ENABLED(CONFIG_PID_IN_CONTEXTIDR) && perfmon_capable()) + if (IS_ENABLED(CONFIG_PID_IN_CONTEXTIDR) && !perf_allow_kernel(&event->attr)) event->hw.flags |= SPE_PMU_HW_FLAGS_CX; } @@ -767,9 +767,8 @@ static int arm_spe_pmu_event_init(struct perf_event *event) set_spe_event_has_cx(event); reg = arm_spe_event_to_pmscr(event); - if (!perfmon_capable() && - (reg & (PMSCR_EL1_PA | PMSCR_EL1_PCT))) - return -EACCES; + if (reg & (PMSCR_EL1_PA | PMSCR_EL1_PCT)) + return perf_allow_kernel(&event->attr); return 0; } diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 95d4118ee4a91..7a5563ffe61b5 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1599,13 +1599,7 @@ static inline int perf_is_paranoid(void) return sysctl_perf_event_paranoid > -1; } -static inline int perf_allow_kernel(struct perf_event_attr *attr) -{ - if (sysctl_perf_event_paranoid > 1 && !perfmon_capable()) - return -EACCES; - - return security_perf_event_open(attr, PERF_SECURITY_KERNEL); -} +int perf_allow_kernel(struct perf_event_attr *attr); static inline int perf_allow_cpu(struct perf_event_attr *attr) { diff --git a/kernel/events/core.c b/kernel/events/core.c index 4d0abdace4e7c..d40809bdf4b30 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -13330,6 +13330,15 @@ const struct perf_event_attr *perf_event_attrs(struct perf_event *event) return &event->attr; } +int perf_allow_kernel(struct perf_event_attr *attr) +{ + if (sysctl_perf_event_paranoid > 1 && !perfmon_capable()) + return -EACCES; + + return security_perf_event_open(attr, PERF_SECURITY_KERNEL); +} +EXPORT_SYMBOL_GPL(perf_allow_kernel); + /* * Inherit an event from parent task to child task. * -- 2.43.0