From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6028DECDFC0 for ; Tue, 11 Sep 2018 09:26:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 161E620865 for ; Tue, 11 Sep 2018 09:26:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="SrNg/AC5"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="SrNg/AC5" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 161E620865 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726912AbeIKOZF (ORCPT ); Tue, 11 Sep 2018 10:25:05 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:44420 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726569AbeIKOZE (ORCPT ); Tue, 11 Sep 2018 10:25:04 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id D08E9609BD; Tue, 11 Sep 2018 09:26:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1536657997; bh=je+ux1fNPM0rDNJIXO6MU0PLVknQA2juJxQKvdOojWQ=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=SrNg/AC5tSxxtHDuYxW+R1PeJMJ0GGulqwSwNc+6Zqcozct0+fOnytmZBm4oOkxYS 2e6F42XnpO4lfh4g8CkzeFiIPJVbMnbfNd7D2+udVLq8VGE2Ei67ojTfTk6qEbfNtM Boz297B/7+8z3fm6VTbqqAw5DvJ77RM8dOArLofs= Received: from [10.204.110.203] (blr-c-bdr-fw-01_globalnat_allzones-outside.qualcomm.com [103.229.19.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: rohitkr@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id D9526607EB; Tue, 11 Sep 2018 09:26:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1536657997; bh=je+ux1fNPM0rDNJIXO6MU0PLVknQA2juJxQKvdOojWQ=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=SrNg/AC5tSxxtHDuYxW+R1PeJMJ0GGulqwSwNc+6Zqcozct0+fOnytmZBm4oOkxYS 2e6F42XnpO4lfh4g8CkzeFiIPJVbMnbfNd7D2+udVLq8VGE2Ei67ojTfTk6qEbfNtM Boz297B/7+8z3fm6VTbqqAw5DvJ77RM8dOArLofs= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org D9526607EB Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=rohitkr@codeaurora.org Subject: Re: [alsa-devel] [PATCH] ASoC: Fix UBSAN warning at snd_soc_get/put_volsw_sx() To: Takashi Iwai Cc: rohkumar@qti.qualcomm.com, alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org, lgirdwood@gmail.com, broonie@kernel.org References: <1536600836-12153-1-git-send-email-rohitkr@codeaurora.org> From: Rohit Kumar Message-ID: <3ac92f3a-059f-3513-4942-23eb41222490@codeaurora.org> Date: Tue, 11 Sep 2018 14:56:32 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Thanks Takashi for reviewing. On 9/10/2018 11:56 PM, Takashi Iwai wrote: > On Mon, 10 Sep 2018 19:33:56 +0200, > Rohit kumar wrote: >> In functions snd_soc_get_volsw_sx() or snd_soc_put_volsw_sx(), >> if the result of (min + max) is negative, then fls() returns >> signed integer with value as 32. This leads to signed integer >> overflow as complete operation is considered as signed integer. >> >> UBSAN: Undefined behaviour in sound/soc/soc-ops.c:382:50 >> signed integer overflow: >> -2147483648 - 1 cannot be represented in type 'int' >> Call trace: >> [] __dump_stack lib/dump_stack.c:15 [inline] >> [] dump_stack+0xec/0x158 lib/dump_stack.c:51 >> [] ubsan_epilogue+0x18/0x50 lib/ubsan.c:164 >> [] handle_overflow+0xf8/0x130 lib/ubsan.c:195 >> [] __ubsan_handle_sub_overflow+0x34/0x44 lib/ubsan.c:211 >> [] snd_soc_get_volsw_sx+0x1a8/0x1f8 sound/soc/soc-ops.c:382 >> >> Typecast the operation to unsigned int to fix the issue. >> >> Signed-off-by: Rohit kumar >> --- >> sound/soc/soc-ops.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/sound/soc/soc-ops.c b/sound/soc/soc-ops.c >> index 592efb3..f8e3190 100644 >> --- a/sound/soc/soc-ops.c >> +++ b/sound/soc/soc-ops.c >> @@ -373,7 +373,7 @@ int snd_soc_get_volsw_sx(struct snd_kcontrol *kcontrol, >> unsigned int rshift = mc->rshift; >> int max = mc->max; >> int min = mc->min; >> - unsigned int mask = (1 << (fls(min + max) - 1)) - 1; >> + unsigned int mask = ((unsigned int)(1 << (fls(min + max) - 1)) - 1); > Cat it be simpler like below instead? > unsigned int mask = (1U << (fls(min + max) - 1)) - 1; Yes, let me just update it. > > thanks, > > Takashi > >> unsigned int val; >> int ret; >> >> @@ -418,7 +418,7 @@ int snd_soc_put_volsw_sx(struct snd_kcontrol *kcontrol, >> unsigned int rshift = mc->rshift; >> int max = mc->max; >> int min = mc->min; >> - unsigned int mask = (1 << (fls(min + max) - 1)) - 1; >> + unsigned int mask = ((unsigned int)(1 << (fls(min + max) - 1)) - 1); >> int err = 0; >> unsigned int val, val_mask, val2 = 0; >> >> -- >> Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc., >> is a member of Code Aurora Forum, a Linux Foundation Collaborative Project. >> >> > _______________________________________________ > Alsa-devel mailing list > Alsa-devel@alsa-project.org > http://mailman.alsa-project.org/mailman/listinfo/alsa-devel Thanks, Rohit