From patchwork Tue Oct 18 20:27:34 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 617484 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0EDEFC4332F for ; Tue, 18 Oct 2022 20:27:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229889AbiJRU1s (ORCPT ); Tue, 18 Oct 2022 16:27:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33870 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229604AbiJRU1r (ORCPT ); Tue, 18 Oct 2022 16:27:47 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6A4D47F13F; Tue, 18 Oct 2022 13:27:47 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 05B7D616EA; Tue, 18 Oct 2022 20:27:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A16D7C433D6; Tue, 18 Oct 2022 20:27:45 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="AfpjIH9c" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1666124863; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Z9dNg5RUH3ZUYvEP9bPk55wn/6KP5eKiCL7817xOPJo=; b=AfpjIH9cDCFgTUBq9oDwFF23ExG/kMnTNG/BdqNSodzUqas/Qs1Ff+i/Tkfdk3qCikxF2A Gf1m5C/q+h9bIvjQfT62a63b1Gd1YOBJqzdqAtD7sPIpvc6Ugpa1AJlT5JSGx84LUXVQ4o nTBiOSN2Eqnjn7VirEb05LDPLfwmF2E= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 3a8f4031 (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Tue, 18 Oct 2022 20:27:43 +0000 (UTC) From: "Jason A. Donenfeld" To: linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: "Jason A. Donenfeld" , Andrew Morton , Andy Shevchenko , Stanislaw Gruszka , Helmut Schaa , Kalle Valo Subject: [PATCH] wifi: rt2x00: use explicitly signed type for clamping Date: Tue, 18 Oct 2022 14:27:34 -0600 Message-Id: <20221018202734.140489-1-Jason@zx2c4.com> In-Reply-To: <202210190108.ESC3pc3D-lkp@intel.com> References: <202210190108.ESC3pc3D-lkp@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On some platforms, `char` is unsigned, which makes casting -7 to char overflow, which in turn makes the clamping operation bogus. Instead, deal with an explicit `s8` type, so that the comparison is always signed, and return an s8 result from the function as well. Note that this function's result is assigned to a `short`, which is always signed. Cc: Andrew Morton Cc: Andy Shevchenko Cc: Stanislaw Gruszka Cc: Helmut Schaa Cc: Kalle Valo Signed-off-by: Jason A. Donenfeld --- drivers/net/wireless/ralink/rt2x00/rt2800lib.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/net/wireless/ralink/rt2x00/rt2800lib.c b/drivers/net/wireless/ralink/rt2x00/rt2800lib.c index cbbb1a4849cf..e233ef9892b3 100644 --- a/drivers/net/wireless/ralink/rt2x00/rt2800lib.c +++ b/drivers/net/wireless/ralink/rt2x00/rt2800lib.c @@ -4035,23 +4035,23 @@ static void rt2800_iq_calibrate(struct rt2x00_dev *rt2x00dev, int channel) rt2800_bbp_write(rt2x00dev, 159, cal != 0xff ? cal : 0); } -static char rt2800_txpower_to_dev(struct rt2x00_dev *rt2x00dev, +static s8 rt2800_txpower_to_dev(struct rt2x00_dev *rt2x00dev, unsigned int channel, - char txpower) + s8 txpower) { if (rt2x00_rt(rt2x00dev, RT3593) || rt2x00_rt(rt2x00dev, RT3883)) txpower = rt2x00_get_field8(txpower, EEPROM_TXPOWER_ALC); if (channel <= 14) - return clamp_t(char, txpower, MIN_G_TXPOWER, MAX_G_TXPOWER); + return clamp_t(s8, txpower, MIN_G_TXPOWER, MAX_G_TXPOWER); if (rt2x00_rt(rt2x00dev, RT3593) || rt2x00_rt(rt2x00dev, RT3883)) - return clamp_t(char, txpower, MIN_A_TXPOWER_3593, + return clamp_t(s8, txpower, MIN_A_TXPOWER_3593, MAX_A_TXPOWER_3593); else - return clamp_t(char, txpower, MIN_A_TXPOWER, MAX_A_TXPOWER); + return clamp_t(s8, txpower, MIN_A_TXPOWER, MAX_A_TXPOWER); } static void rt3883_bbp_adjust(struct rt2x00_dev *rt2x00dev,