From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.11]) (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 AF7B2399036 for ; Mon, 23 Mar 2026 13:27:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774272458; cv=none; b=FOKQ3aGTJZ60OrW89AvSTv4qiNx5AbUIn0+dOo9WGy8d4rlhMPFlfIvwqWeWGQh5gFGq8A6uD+mDJ8sVR28aWEn4bvogJ1J9HWVTq2w/rRsT8MSJxOu125zB5b+ZUfoLNx3yFyKZwgTSXTYEs4P7rtOsCKenzbxzHwaqQoRQ4no= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774272458; c=relaxed/simple; bh=58ExM2Q489hxnN4iueUkyVFhOyh8xkuQ/H2oBnKU2Yo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ph1H2C8SyYl/jmJJyN+SQknmn5SkNZWmeCq9KKrOImCZfx5AF3fpVf0ODavR7GbuM5F1UcnTbPBNru7iCiSexSoGgHaQbVNIDYtvIlNkWp3pxvhxDn1P2REBDqCt/hg5MqecqR0uFt9KknWjT8Sd88kerlIpVlaECFggcJKb8Hk= 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=GXgeIS5a; arc=none smtp.client-ip=198.175.65.11 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="GXgeIS5a" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1774272457; x=1805808457; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=58ExM2Q489hxnN4iueUkyVFhOyh8xkuQ/H2oBnKU2Yo=; b=GXgeIS5agkBJpM5Kd9RtCDv02dw+3GBuOSEfUVZb3t7PMDVaUtGfG78B BQpR+RTWno84GhjR5zAR3ip1lpugWZAFVr6NclEXXDmjNvS1fNrEl8ZVB yGO0ctM694UIjzpoGz8171T/tWhMYEDb/DlaL7mcxUaKzI6DWntV6X7eb dQpTsHpe4TOczq2VHx57S52oqvYk9ljlNiEPAi1co27ImpRFC+qqNocZZ XG5xDaL7Z6i8g8oMFWYq3Z6BcikFYwAyWFwjGSvHUAJreawFR5Xx9BDqd cu+Fbpd3Le/7kPX+jYJdcG7Fa5UFjll9BeACqSzbnF7ayoE+LgJrhfJp8 g==; X-CSE-ConnectionGUID: SmJwcXAzQRusyCyOH1I88g== X-CSE-MsgGUID: nLhExan4Rsm0kxyARWjc2A== X-IronPort-AV: E=McAfee;i="6800,10657,11737"; a="85580433" X-IronPort-AV: E=Sophos;i="6.23,137,1770624000"; d="scan'208";a="85580433" Received: from fmviesa009.fm.intel.com ([10.60.135.149]) by orvoesa103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Mar 2026 06:27:37 -0700 X-CSE-ConnectionGUID: YcP/RGdERTWjIB58lJXY5Q== X-CSE-MsgGUID: +iHAMCssSWG1TXDmtKcxWQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,137,1770624000"; d="scan'208";a="217527036" Received: from vpanait-mobl.ger.corp.intel.com (HELO localhost) ([10.245.244.22]) by fmviesa009-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Mar 2026 06:27:34 -0700 Date: Mon, 23 Mar 2026 15:27:31 +0200 From: Andy Shevchenko To: "Masami Hiramatsu (Google)" Cc: Petr Mladek , Steven Rostedt , Rasmus Villemoes , Sergey Senozhatsky , Andrew Morton , David Laight , linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 1/2] lib/vsprintf: Fix to check field_width and precision Message-ID: References: <177410406326.38798.16853803119128725972.stgit@devnote2> <177410407207.38798.2345647618225402693.stgit@devnote2> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <177410407207.38798.2345647618225402693.stgit@devnote2> Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo On Sat, Mar 21, 2026 at 11:41:12PM +0900, Masami Hiramatsu (Google) wrote: > Check the field_width and presition correctly. Previously it depends > on the bitfield conversion from int to check out-of-range error. > However, commit 938df695e98d ("vsprintf: associate the format state > with the format pointer") changed those fields to int. > We need to check the out-of-range correctly without bitfield > conversion. ... > static void > set_field_width(struct printf_spec *spec, int width) > { > - spec->field_width = width; > - if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { > - spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); > + if (WARN_ONCE(width > FIELD_WIDTH_MAX || width < -FIELD_WIDTH_MAX, > + "field width %d too large", width)) { > + width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); > } > + spec->field_width = width; > } > > static void > set_precision(struct printf_spec *spec, int prec) > { > - spec->precision = prec; > - if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { > - spec->precision = clamp(prec, 0, PRECISION_MAX); > + if (WARN_ONCE(prec > PRECISION_MAX || prec < 0, > + "precision %d too large", prec)) { > + prec = clamp(prec, 0, PRECISION_MAX); > } > + spec->precision = prec; > } Looking at this, perhaps #define clamp_WARN_*(...) ... Potential users besides these two: arch/powerpc/platforms/pseries/papr-sysparm.c-39- drivers/gpu/drm/drm_color_mgmt.c-142- drivers/gpu/drm/i915/display/intel_backlight.c-48- drivers/media/i2c/vgxy61.c-952- -- With Best Regards, Andy Shevchenko