From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.17]) (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 A27D9382F1E; Tue, 9 Jun 2026 05:08:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.17 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780981699; cv=none; b=BshoyF50uf8U/uh9xb8J9w5uwGCjOPx2yEyx/fkWY/ChNZ4+cWwUwj6WA8skwgnubqW1wuw9ZiaZhOwHLywQ404uMmPDqR07FjAxz1jEmqaiZlCA/K75OIXbeLmAO/8ILk9MfWvMADblV5Q4I51vI0lQmakM+Cp/s/rMytr4TP0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780981699; c=relaxed/simple; bh=0opGLz58tqOBQk0g3QkpKG/34nOsQ+Ls31VCt62BZAM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=I3wkLCiW3YP/f5CdlNJ0Hj2wzYTjLaMmkvtgMaMT8V32QTQwkg9ziWCvH5HHjqHhCGijdy+m1JyRwOEo1lO8cpfkWJ0vvYsetz/lSvCvuOoXC15jzhAe5Ofh2N9wdVR4DHxE8aiAT28eMmChUqIW59kQ8HR+r6PxG5+WiqKVfKY= 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=lY4BN1mI; arc=none smtp.client-ip=192.198.163.17 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="lY4BN1mI" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1780981699; x=1812517699; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=0opGLz58tqOBQk0g3QkpKG/34nOsQ+Ls31VCt62BZAM=; b=lY4BN1mIFyXJE4MxUHY4yYp8ot5MnKNakfFQ8x5n8EECIZPNTS2DEdZ7 9/g0d45mkOIQWkOodkjfugsHP6QZLDVOZDFp0JBkZPHS6EtK6jUIbYB9W Iu0XG+phD6WjrmmX2Drj/6kRdEo4nfFKOPmowiG3BVMzuh5NY5tBtQQe9 MudnoG1VVddL2zBN2+2c9AeqEzrXADIID1VVWrWXJPW8hfjEHdq1c+OVW ZMjOJpGbjneCtDOCR+58euTUnt1YjkJ4fum/1AoML07wtr1T8FQgoYq6c N0weIuHzttB2C2O5GvlR8VHugjD+GcWihi7qv+d1ZzOIdfaMPO8JEmbqE Q==; X-CSE-ConnectionGUID: PJw/d0kCQlK93ksL5wm4mA== X-CSE-MsgGUID: 4zHON8w+SbSfqVSRSJqjRg== X-IronPort-AV: E=McAfee;i="6800,10657,11811"; a="81586206" X-IronPort-AV: E=Sophos;i="6.24,195,1774335600"; d="scan'208";a="81586206" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by fmvoesa111.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Jun 2026 22:08:18 -0700 X-CSE-ConnectionGUID: l+nGj0DoRLeLmDqdMOLfzQ== X-CSE-MsgGUID: VXgNcThnQdqGw6Hh7LvXVA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.24,195,1774335600"; d="scan'208";a="283838940" Received: from spr.sh.intel.com ([10.112.230.239]) by orviesa001.jf.intel.com with ESMTP; 08 Jun 2026 22:08:14 -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 v2 9/9] perf/core: Check kernel access when kernel callchains are requested Date: Tue, 9 Jun 2026 13:02:22 +0800 Message-Id: <20260609050222.2458129-10-dapeng1.mi@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260609050222.2458129-1-dapeng1.mi@linux.intel.com> References: <20260609050222.2458129-1-dapeng1.mi@linux.intel.com> Precedence: bulk X-Mailing-List: linux-perf-users@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 1bde029eeca7..57c9fd640cf5 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -13895,7 +13895,9 @@ 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