From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.15]) (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 88A2D3CB916; Tue, 16 Jun 2026 04:53:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.15 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781585585; cv=none; b=tk+CNftnySnuV7aW1qagp/Vxhz5K/r8G291QY+wWSbPnOa105JVOAPh/UB/iyoj9dIdIvS9WAnof/MgzBR3Q6chBlzzwqlJBDNrXSxm3W3oX/p1/Bzg3wJe/1oEp6r995AqtTO8ITCDxHketYJaeIIzOVdtZBYCrLHelPw/s18U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781585585; c=relaxed/simple; bh=mly2iaCfBkjoH7gmdQqUuuX71xCZ4hm2aMsANOSobHI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=uuossfkj6j92uxHKmeOfHJReCA9LVoOoWg6po20V+I0xhXOuFIEYs1vQi8tWHGpDWkLqJlRn5mRjAiMK/QyvVPH1Ikf/b5/8VR3TGd/I1ZUlfAvj2zA8ZVwEy18F8dgeqMgaW57Fmb2bOY/0e7F578OL4Xq7uyQWqN1Veb/OJLY= 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=VzkTp9qK; arc=none smtp.client-ip=192.198.163.15 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="VzkTp9qK" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1781585583; x=1813121583; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=mly2iaCfBkjoH7gmdQqUuuX71xCZ4hm2aMsANOSobHI=; b=VzkTp9qKNskDHxPKUkXekuzRoDbNkgUQYhYFOCvQEnqe4oCA1cOIhbpP 8OpDRdP7y0ph7eZ28gV7fKAUvYlJOFdo/WJb/HPj4IL9iToYBOEU0rjbA fNCn5Xwd2buCR1znCZXENyMMcDoe9T0UHtOTw8a6zQxsCwraLYwd07vTE 6M9+X5psnf+t3QhsCwETeiFUiU6jDjEsXk0GKztZQFc6swcGJs0a7Cw9t 61G57z3RbSioFngiqgv+f8kaPHnz5IYFP9aGkZYWdDUHKJSBtwbO3A01o 79Xe1ulrQffXodeUQ/dWi3g33mY/jMXv3Z9GSnl4RCTHWbqmYQ3GrYPQZ g==; X-CSE-ConnectionGUID: TtYlkVmtSVu/5feYnk2lUw== X-CSE-MsgGUID: sLqCGiVNT3WhXvyHfPWXVA== X-IronPort-AV: E=McAfee;i="6800,10657,11818"; a="82445552" X-IronPort-AV: E=Sophos;i="6.24,207,1774335600"; d="scan'208";a="82445552" Received: from fmviesa001.fm.intel.com ([10.60.135.141]) by fmvoesa109.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Jun 2026 21:53:01 -0700 X-CSE-ConnectionGUID: sSTN3KaSRZiVQ+Wj1j0NAg== X-CSE-MsgGUID: Oduj4eaxTqOx+2+8WMwjqw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.24,207,1774335600"; d="scan'208";a="271726579" Received: from spr.sh.intel.com ([10.112.230.239]) by fmviesa001.fm.intel.com with ESMTP; 15 Jun 2026 21:52:55 -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 v4 8/8] perf/core: Check kernel access when kernel callchains are requested Date: Tue, 16 Jun 2026 12:46:54 +0800 Message-Id: <20260616044654.3468742-9-dapeng1.mi@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260616044654.3468742-1-dapeng1.mi@linux.intel.com> References: <20260616044654.3468742-1-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 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