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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 45C9CC433FE for ; Mon, 21 Nov 2022 10:48:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229831AbiKUKsL (ORCPT ); Mon, 21 Nov 2022 05:48:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49498 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229711AbiKUKsC (ORCPT ); Mon, 21 Nov 2022 05:48:02 -0500 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0E84F1001 for ; Mon, 21 Nov 2022 02:47:31 -0800 (PST) Received: from canpemm500005.china.huawei.com (unknown [172.30.72.57]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4NG3sq0dvDzFqSg; Mon, 21 Nov 2022 18:44:15 +0800 (CST) Received: from [10.174.178.197] (10.174.178.197) by canpemm500005.china.huawei.com (7.192.104.229) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Mon, 21 Nov 2022 18:47:28 +0800 Message-ID: <8e6ba5d1-ed34-1a17-35cb-4b80f1cdb38e@huawei.com> Date: Mon, 21 Nov 2022 18:47:27 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.4.1 Subject: Re: [PATCH -next] ALSA: pcm: fix undefined behavior in bit shift for SNDRV_PCM_RATE_KNOT To: Takashi Iwai CC: , , , , , References: <20221121023329.2423665-1-zhongbaisong@huawei.com> <87h6yswq7c.wl-tiwai@suse.de> From: zhongbaisong Organization: huawei In-Reply-To: <87h6yswq7c.wl-tiwai@suse.de> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.174.178.197] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To canpemm500005.china.huawei.com (7.192.104.229) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2022/11/21 18:35, Takashi Iwai 写道: > On Mon, 21 Nov 2022 03:33:29 +0100, > Baisong Zhong wrote: >> >> Shifting signed 32-bit value by 31 bits is undefined, so changing >> significant bit to unsigned. The UBSAN warning calltrace like below: >> >> UBSAN: shift-out-of-bounds in sound/core/pcm_native.c:2676:21 >> left shift of 1 by 31 places cannot be represented in type 'int' >> ... >> Call Trace: >> >> dump_stack_lvl+0x8d/0xcf >> ubsan_epilogue+0xa/0x44 >> __ubsan_handle_shift_out_of_bounds+0x1e7/0x208 >> snd_pcm_open_substream+0x9f0/0xa90 >> snd_pcm_oss_open.part.26+0x313/0x670 >> snd_pcm_oss_open+0x30/0x40 >> soundcore_open+0x18b/0x2e0 >> chrdev_open+0xe2/0x270 >> do_dentry_open+0x2f7/0x620 >> path_openat+0xd66/0xe70 >> do_filp_open+0xe3/0x170 >> do_sys_openat2+0x357/0x4a0 >> do_sys_open+0x87/0xd0 >> do_syscall_64+0x34/0x80 >> >> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") >> Signed-off-by: Baisong Zhong >> --- >> include/sound/pcm.h | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/include/sound/pcm.h b/include/sound/pcm.h >> index 7b1a022910e8..ec28c2ec89de 100644 >> --- a/include/sound/pcm.h >> +++ b/include/sound/pcm.h >> @@ -123,7 +123,7 @@ struct snd_pcm_ops { >> #define SNDRV_PCM_RATE_384000 (1<<14) /* 384000Hz */ >> >> #define SNDRV_PCM_RATE_CONTINUOUS (1<<30) /* continuous range */ >> -#define SNDRV_PCM_RATE_KNOT (1<<31) /* supports more non-continuos rates */ >> +#define SNDRV_PCM_RATE_KNOT (1U<<31) /* supports more non-continuos rates */ > > Could you rather update all SNDRV_PCM_RATE_* to 1U? > Otherwise it'll look inconsistent. > > > thanks, > > Takashi Hi, Takashi Thank you for your suggestion. I will update all SNDRV_PCM_RATE_* to 1U for consistency in v2. Baisong Zhong .