From nobody Wed Apr 15 19:44:58 2026 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 0C3C9C43219 for ; Mon, 21 Nov 2022 11:22:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230023AbiKULWP (ORCPT ); Mon, 21 Nov 2022 06:22:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46102 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230251AbiKULVf (ORCPT ); Mon, 21 Nov 2022 06:21:35 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9B8EAC1F40 for ; Mon, 21 Nov 2022 03:16:32 -0800 (PST) Received: from canpemm500005.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4NG4VY4QvJzqSNF; Mon, 21 Nov 2022 19:12:37 +0800 (CST) Received: from huawei.com (10.175.104.82) 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 19:16:30 +0800 From: Baisong Zhong To: , CC: , , , Subject: [PATCH -next v2] ALSA: seq: fix undefined behavior in bit shift for SNDRV_SEQ_FILTER_USE_EVENT Date: Mon, 21 Nov 2022 19:16:30 +0800 Message-ID: <20221121111630.3119259-1-zhongbaisong@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.104.82] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) 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 Content-Type: text/plain; charset="utf-8" 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/seq/seq_clientmgr.c:509:22 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_seq_deliver_single_event.constprop.21+0x191/0x2f0 snd_seq_deliver_event+0x1a2/0x350 snd_seq_kernel_client_dispatch+0x8b/0xb0 snd_seq_client_notify_subscription+0x72/0xa0 snd_seq_ioctl_subscribe_port+0x128/0x160 snd_seq_kernel_client_ctl+0xce/0xf0 snd_seq_oss_create_client+0x109/0x15b alsa_seq_oss_init+0x11c/0x1aa do_one_initcall+0x80/0x440 kernel_init_freeable+0x370/0x3c3 kernel_init+0x1b/0x190 ret_from_fork+0x1f/0x30 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Baisong Zhong --- v2: update all SNDRV_SEQ_FILTER_* to 1U to keep consistent --- include/uapi/sound/asequencer.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/include/uapi/sound/asequencer.h b/include/uapi/sound/asequence= r.h index 6d4a2c60808d..00d2703e8fca 100644 --- a/include/uapi/sound/asequencer.h +++ b/include/uapi/sound/asequencer.h @@ -328,10 +328,10 @@ typedef int __bitwise snd_seq_client_type_t; #define KERNEL_CLIENT ((__force snd_seq_client_type_t) 2) =20 /* event filter flags */ -#define SNDRV_SEQ_FILTER_BROADCAST (1<<0) /* accept broadcast messages */ -#define SNDRV_SEQ_FILTER_MULTICAST (1<<1) /* accept multicast messages */ -#define SNDRV_SEQ_FILTER_BOUNCE (1<<2) /* accept bounce event in error */ -#define SNDRV_SEQ_FILTER_USE_EVENT (1<<31) /* use event filter */ +#define SNDRV_SEQ_FILTER_BROADCAST (1U<<0) /* accept broadcast messages */ +#define SNDRV_SEQ_FILTER_MULTICAST (1U<<1) /* accept multicast messages */ +#define SNDRV_SEQ_FILTER_BOUNCE (1U<<2) /* accept bounce event in error */ +#define SNDRV_SEQ_FILTER_USE_EVENT (1U<<31) /* use event filter */ =20 struct snd_seq_client_info { int client; /* client number to inquire */ --=20 2.25.1