From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.15]) (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 B4EC7369203; Fri, 12 Jun 2026 09:07:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.15 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781255229; cv=none; b=qTJZU3qtHgW/9PKao3TCwWjk980NtP76WEkzw0Jb2RZ1mfqIUIEGjbHqriwoiVKvIZYtOfpsvf5abPeSHgJebrfkNQuDqWPjj6/nWktpzKSE+Ex0slRoBp0SL8sXSanTfRL9e4g/qDiFf5mH4KS+Xih1eBl4VHGUsLtQNCFffH8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781255229; c=relaxed/simple; bh=mly2iaCfBkjoH7gmdQqUuuX71xCZ4hm2aMsANOSobHI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Qhieu6iwjzJrIMZXUR70jU1wekACJZndgXXS6/9JZSdzmxuePIN66y4raaW4//i/yoKuCpL0napQjDeIL9Yu/jmL3LqatCpZi8UF4wwCW5vOlqMetQtaZ6JbQ/VwnhsZeGRZecnssJfbQmXIowpmsJX3dIAqRaZ2mteWIUVCygQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=jcTPxbFl; arc=none smtp.client-ip=198.175.65.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="jcTPxbFl" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1781255223; x=1812791223; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=mly2iaCfBkjoH7gmdQqUuuX71xCZ4hm2aMsANOSobHI=; b=jcTPxbFl0M+H9La9JgHgCQNzGDHppuEd21GvE/UMUrAagsspaGU7E8MA 9KcIcaX9ottI/Tjk9YKpFfpWjFPlmzu+P+bc0NxLqRJMdVgRMLAakFF2r DstHBdc8IriwI6fPVfhk1c3HKFoZ+wO1lzsQ9ibm2TduOkhaFs4xjUfC1 jkiUYp/xwKzdN3TfGtCU0FfrK6kfnY+7ST2usiLLsRk+LUDXxZICrecEJ gJfx6XT+kj35h6ZwPlTcnFMOmDis5A1e6GNP64mEts+osliwRba/ig3cm vEA+T7v8qiJMEfxG63QuR3nBq5tt8Cl66lp5CRDV8HNUU40zjO5sO6b1W g==; X-CSE-ConnectionGUID: H10Cae+tSIaUdFrFO7YgVA== X-CSE-MsgGUID: /9Ial7rUScC1F2EeiouAEA== X-IronPort-AV: E=McAfee;i="6800,10657,11813"; a="85714490" X-IronPort-AV: E=Sophos;i="6.24,200,1774335600"; d="scan'208";a="85714490" Received: from orviesa007.jf.intel.com ([10.64.159.147]) by orvoesa107.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Jun 2026 02:07:03 -0700 X-CSE-ConnectionGUID: Y0HchbsRT/6x4S1JxYIVug== X-CSE-MsgGUID: XGs3VX0aThKJqP5nMxANlg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.24,200,1774335600"; d="scan'208";a="246838781" Received: from spr.sh.intel.com ([10.112.230.239]) by orviesa007.jf.intel.com with ESMTP; 12 Jun 2026 02:06:59 -0700 From: Dapeng Mi To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Ian Rogers , Adrian Hunter , Alexander Shishkin , Andi Kleen , Eranian Stephane Cc: linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Dapeng Mi , Zide Chen , Falcon Thomas , Xudong Hao , Dapeng Mi , Mark Rutland Subject: [Patch v3 8/8] perf/core: Check kernel access when kernel callchains are requested Date: Fri, 12 Jun 2026 17:01:14 +0800 Message-Id: <20260612090114.3188886-9-dapeng1.mi@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260612090114.3188886-1-dapeng1.mi@linux.intel.com> References: <20260612090114.3188886-1-dapeng1.mi@linux.intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit perf_event_open() currently gates perf_allow_kernel() only on !attr.exclude_kernel. However, users can still request kernel callchain collection with attr.exclude_callchain_kernel == 0 even when attr.exclude_kernel == 1. That still requires kernel profiling privilege, but the existing check does not enforce it. Update the permission check to call perf_allow_kernel() when either kernel sampling is requested or kernel callchains are requested. This keeps permission checks aligned with requested data and prevents unprivileged use of kernel callchain capture. Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Mark Rutland Cc: Arnaldo Carvalho de Melo Cc: Namhyung Kim Cc: Ian Rogers Signed-off-by: Dapeng Mi --- kernel/events/core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 89f6c9ffb964..bbd260d9d5b5 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -13924,7 +13924,9 @@ SYSCALL_DEFINE5(perf_event_open, if (err) return err; - if (!attr.exclude_kernel) { + if (!attr.exclude_kernel || + ((attr.sample_type & PERF_SAMPLE_CALLCHAIN) && + !attr.exclude_callchain_kernel)) { err = perf_allow_kernel(); if (err) return err; -- 2.34.1