From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.7]) (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 DDE693115BD; Thu, 23 Apr 2026 18:44:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.7 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776969878; cv=none; b=dhNx19ZZB3xg6cJSdZysbFQRvTpU9nqdqARcqqsKSww8ldPMDlN0xaQt+iQkMPas7aLEJk5Cr9+XX+pSJ1y1bWX7T9Duq4XTKUkFeGYCVke/3Zlp8/BH6WipOu+8c1OJAeLatSyPtwCrIB8yQ2TIqgWotpA0sPfVT6wIAFlfIhE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776969878; c=relaxed/simple; bh=29xIrSc9fAng9oxyMetklAp6GoFdN2zWt3fs9gbX0wM=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=ce1TAfYjr1cKFLd1+rVtjngJHqRcVTL96rF5I7Lo2HzXiznbOALumW3JZxHhxvaKAeaEK46YLZnfBBA/UzdUKVPEeqX3SSM+EN83KiESOBnl1IfgoYurH9aUgtgoXm4DdNXIL/JjUVUIaQvurqPncBvDpGfV1RSbtah6UoLZEII= 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=U8pOrfYi; arc=none smtp.client-ip=192.198.163.7 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="U8pOrfYi" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1776969877; x=1808505877; h=message-id:subject:from:to:cc:date:in-reply-to: references:content-transfer-encoding:mime-version; bh=29xIrSc9fAng9oxyMetklAp6GoFdN2zWt3fs9gbX0wM=; b=U8pOrfYi3x4ckU3kn6PFbgrCzL2E89y9GV8lmQet/qbwXLff2RhDGzy0 BS+YPJRQAWI6qTZrXSCYNkrkpCUhCwgSSut4uqSvrWr3XcR8rS/JxqV8v /A/6AtzgI6l2bHJCBmjxHiU2zU1J+o3cAnwhweA3sGml/SvPxUSPqEGRl Jvi9vbWUCl6Ma3pmdsL2GBMdom4Y0n8qovCoyYZF2nQiROhLTfTydGRz4 aR++cDbi6s8Q7V3YgCjwLfkHyIpQYP/vkujBFBm5eOk01vhSkFfkQLFJ2 lR5Zp0kIBxCEOiUr/TJ4XlZPBJzBSwvfW+uKcN71/FO5/N4CHAaiGgnLv Q==; X-CSE-ConnectionGUID: An282dXPQ2yZf43l3y4aIA== X-CSE-MsgGUID: MBw6UVhfQAe1/GoBImpNJQ== X-IronPort-AV: E=McAfee;i="6800,10657,11765"; a="103410729" X-IronPort-AV: E=Sophos;i="6.23,195,1770624000"; d="scan'208";a="103410729" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Apr 2026 11:44:36 -0700 X-CSE-ConnectionGUID: sNrhpqyRQ2Kjq6SLHvvGRg== X-CSE-MsgGUID: A2W7ShlRRmuNOaQld+qNSA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,195,1770624000"; d="scan'208";a="270857023" Received: from dnelso2-mobl.amr.corp.intel.com (HELO [10.125.108.31]) ([10.125.108.31]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Apr 2026 11:44:36 -0700 Message-ID: Subject: Re: [PATCH] tools/power/x86/intel-speed-select: harden daemon pidfile open From: srinivas pandruvada To: unknownbbqrx Cc: platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org Date: Thu, 23 Apr 2026 11:44:35 -0700 In-Reply-To: <0e8607ca-1275-4ee2-9539-0af0ec17ae90@smtp-relay.sendinblue.com> References: <0e8607ca-1275-4ee2-9539-0af0ec17ae90@smtp-relay.sendinblue.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.3 (3.58.3-1.fc43) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Thanks for this change. Capitalize the first letter. here it will be "Harden daemon pidfile open" On Thu, 2026-04-23 at 20:16 +0300, unknownbbqrx wrote: >=20 > Avoid symlink-based pidfile clobbering by opening the pidfile with > O_NOFOLLOW and validating it with fstat() before locking/writing. >=20 > The daemon currently uses a fixed pidfile path under /tmp. A local > unprivileged user can pre-create a symlink at that path and cause a > root-run daemon instance to write into an attacker-chosen file. >=20 > Signed-off-by: unknownbbqrx Please follow sign-off guidelines https://docs.kernel.org/process/submitting-patches.html Thanks, Srinivas > --- > =C2=A0tools/power/x86/intel-speed-select/isst-daemon.c | 12 +++++++++++- > =C2=A01 file changed, 11 insertions(+), 1 deletion(-) >=20 > diff --git a/tools/power/x86/intel-speed-select/isst-daemon.c > b/tools/power/x86/intel-speed-select/isst-daemon.c > index 66df21b2b..4346b049d 100644 > --- a/tools/power/x86/intel-speed-select/isst-daemon.c > +++ b/tools/power/x86/intel-speed-select/isst-daemon.c > @@ -200,11 +200,21 @@ static void daemonize(char *rundir, char > *pidfile) > =C2=A0 if (ret =3D=3D -1) > =C2=A0 exit(EXIT_FAILURE); > =C2=A0 > - pid_file_handle =3D open(pidfile, O_RDWR | O_CREAT, 0600); > + pid_file_handle =3D open(pidfile, O_RDWR | O_CREAT | > O_NOFOLLOW, 0600); > =C2=A0 if (pid_file_handle =3D=3D -1) { > =C2=A0 /* Couldn't open lock file */ > =C2=A0 exit(1); > =C2=A0 } > + > + { > + struct stat st; > + > + if (fstat(pid_file_handle, &st) =3D=3D -1) > + exit(1); > + > + if (!S_ISREG(st.st_mode)) > + exit(1); > + } > =C2=A0 /* Try to lock file */ > =C2=A0#ifdef LOCKF_SUPPORT > =C2=A0 if (lockf(pid_file_handle, F_TLOCK, 0) =3D=3D -1) { >=20 > base-commit: 2e68039281932e6dc37718a1ea7cbb8e2cda42e6 > prerequisite-patch-id: b61dd51dee390277603975bf729a687113185c3a > prerequisite-patch-id: df28525061dd528875c7c75880b4684d80f4aa7d