From nobody Sat Nov 30 04:36:12 2024 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.21]) (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 83D6B1BF81D; Thu, 12 Sep 2024 18:04:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.21 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726164297; cv=none; b=WAGiieN9KdM6Tf+0Kmd0zQPn50cYu32vtgqaaJvonhmxQh3eHCsfPLnaFajPoh887AsKw/Oikd7El4JU+dq3O4wFr8kwdB86dBrM10jR02ZZ+xpFz4yjTZAKoC260H+GDJ0dA19Ls/LjQ8LCWtw2as/2wDfV2O8Rk1iRvim7rxY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726164297; c=relaxed/simple; bh=Vb6zyOzim1npQb7wI5cEfqF7g7w9rDJNBCyNthUbBX4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ttcU/HiHtwUA7W4vY19Dm3hEHBoew+ZZhVDw2LXnctRxpGIYFJHz7VQkN4KBJ6zojnsEOJXF7c9541brsErM7+0fQJrgLa/Udsf9fU58QI2y4EOYHOaIe3q8rSPNdg+lAmXrAtWEDTiz0RvwTEHKHdQLcuZwyOCCMgGENLqrogU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=URR0smUo; arc=none smtp.client-ip=198.175.65.21 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="URR0smUo" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1726164296; x=1757700296; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Vb6zyOzim1npQb7wI5cEfqF7g7w9rDJNBCyNthUbBX4=; b=URR0smUoKRB0Mtqb3+xSpY5na+RF+P+nOxPcA1NHZdoar4d40Pl1lUt+ mgLKxoLU2JVV/CMyT2JsfBrpybL9TTxD4uRyeZl70TEL3cenPOyvZfW4A s9ohgKOFbQJOyMCcT+aSM2tg80V1tvg1PUCi1HXpNQZ75cPPD49oGXYrK 3mVy28b2lltkxhdSWu1b8yAImAT+V4quYFJIaLTdoD8mzYr2Qs4jr/XqZ qXIXf2Q0JdDKvVsKGi7yvd5psiWoipKmSDLqeIPZWLamJA9jbVRRWHc6F iqCCH1stLswsWD7pnXrfi2Lv/xM8Cb8hftd2gZrpSdiQmIOJlo6S7rrp7 w==; X-CSE-ConnectionGUID: cmuHY064Q4Onzkob1nZwlA== X-CSE-MsgGUID: f1N+9KJ2T5qKYtov8cDa1w== X-IronPort-AV: E=McAfee;i="6700,10204,11193"; a="24976586" X-IronPort-AV: E=Sophos;i="6.10,223,1719903600"; d="scan'208";a="24976586" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Sep 2024 11:04:53 -0700 X-CSE-ConnectionGUID: e7E+PrSQQsWIYIOdCvR79w== X-CSE-MsgGUID: pXvWAwzoSJi81N7XB4R7Mw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,223,1719903600"; d="scan'208";a="67724609" Received: from b04f130c85c0.jf.intel.com (HELO rchatre-desk1.jf.intel.com) ([10.165.154.99]) by orviesa009-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Sep 2024 11:04:52 -0700 From: Reinette Chatre To: fenghua.yu@intel.com, shuah@kernel.org, tony.luck@intel.com, peternewman@google.com, babu.moger@amd.com, ilpo.jarvinen@linux.intel.com Cc: maciej.wieczor-retman@intel.com, reinette.chatre@intel.com, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH V2 04/13] selftests/resctrl: Protect against array overrun during iMC config parsing Date: Thu, 12 Sep 2024 11:13:53 -0700 Message-ID: X-Mailer: git-send-email 2.46.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The MBM and MBA tests need to discover the event and umask with which to configure the performance event used to measure read memory bandwidth. This is done by parsing the /sys/bus/event_source/devices/uncore_imc_/events/cas_count_re= ad file for each iMC instance that contains the formatted output: "event=3D,umask=3D" Parsing of cas_count_read contents is done by initializing an array of MAX_TOKENS elements with tokens (deliminated by "=3D,") from this file. Start by removing the unnecessary append of a delimiter to the string needing to be parsed. Per the strtok() man page: "delimiter bytes at the start or end of the string are ignored". This has no impact on the token placement within the array. After initialization, the actual event and umask is determined by parsing the tokens directly following the "event" and "umask" tokens respectively. Iterating through the array up to index "i < MAX_TOKENS" but then accessing index "i + 1" risks array overrun during the final iteration. Avoid array overrun by ensuring that the index used within for loop will always be valid. Fixes: 1d3f08687d76 ("selftests/resctrl: Read memory bandwidth from perf IM= C counter and from resctrl file system") Signed-off-by: Reinette Chatre Reviewed-by: Ilpo J=C3=A4rvinen --- Changes since V1: - New patch. --- tools/testing/selftests/resctrl/resctrl_val.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/= selftests/resctrl/resctrl_val.c index 70e8e31f5d1a..e88d5ca30517 100644 --- a/tools/testing/selftests/resctrl/resctrl_val.c +++ b/tools/testing/selftests/resctrl/resctrl_val.c @@ -83,13 +83,12 @@ static void get_event_and_umask(char *cas_count_cfg, in= t count, bool op) char *token[MAX_TOKENS]; int i =3D 0; =20 - strcat(cas_count_cfg, ","); token[0] =3D strtok(cas_count_cfg, "=3D,"); =20 for (i =3D 1; i < MAX_TOKENS; i++) token[i] =3D strtok(NULL, "=3D,"); =20 - for (i =3D 0; i < MAX_TOKENS; i++) { + for (i =3D 0; i < MAX_TOKENS - 1; i++) { if (!token[i]) break; if (strcmp(token[i], "event") =3D=3D 0) { --=20 2.46.0