From patchwork Thu Sep 1 17:50:21 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cezary Rojewski X-Patchwork-Id: 12963020 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 alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 91E33ECAAD1 for ; Thu, 1 Sep 2022 17:42:01 +0000 (UTC) Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 8EEC5163D; Thu, 1 Sep 2022 19:41:09 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 8EEC5163D DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1662054119; bh=QpLq53kDMbsQj6L9fHeAwbwgO0XWugT9uvq/PRVvdGI=; h=From:To:Subject:Date:In-Reply-To:References:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=c74Fnr0uK84pq5MGYTooiutF+rfip1wswP74h4pBACqn5/9xOidhM6R4CfMD5do8l 4Uxe1nKogo/MOwLiSGHLUUFlgF281vamHeMzSYui2xAk/8oj1Wv8o/h0F0F2MIBpgN z6t1iXPY8I7NvVMFzC+FDe1L4Z3PfI/eqOLIOtK8= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id CC6F0F804CF; Thu, 1 Sep 2022 19:40:42 +0200 (CEST) Received: by alsa1.perex.cz (Postfix, from userid 50401) id DBBF4F80525; Thu, 1 Sep 2022 19:40:41 +0200 (CEST) Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id 2F89CF8026A for ; Thu, 1 Sep 2022 19:40:34 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 2F89CF8026A Authentication-Results: alsa1.perex.cz; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="a0Fjy31w" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1662054036; x=1693590036; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=QpLq53kDMbsQj6L9fHeAwbwgO0XWugT9uvq/PRVvdGI=; b=a0Fjy31ws1/4hQADh6NwGM9opAHFPMZwojaWBgBQtUgYiWrf38HIwhKH mONSOU7ASuhRXbl2rWRS/KfHJ9nSXyt4VKKBb16uE+8740dfEhVyN6SV+ 4RmXeyCSEemBIAI60BN8AhTKInOttcQdwlBejTY2TMG6JgnIcPMmx2djm BcGVwzQhUNJBacmAyWByBRJKW/a8SA+9I7y06Eklg4PYAB6660e/PtgYu fYryXDfmTQ44QRZvdvdZzdaKG5obBgSdw4Qq4yvFBy2JsgfrmcyuRCbOt 2mcoQpmwO1E5eb4IfM++4U9IX+/PySaF3VKC0TPyojC/PEzQWSExkCAfI Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10457"; a="295792339" X-IronPort-AV: E=Sophos;i="5.93,281,1654585200"; d="scan'208";a="295792339" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Sep 2022 10:40:33 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.93,281,1654585200"; d="scan'208";a="680960379" Received: from crojewsk-ctrl.igk.intel.com ([10.102.9.28]) by fmsmga004.fm.intel.com with ESMTP; 01 Sep 2022 10:40:29 -0700 From: Cezary Rojewski To: alsa-devel@alsa-project.org, broonie@kernel.org Subject: [PATCH v3 1/2] lib/string_helpers: Introduce tokenize_user_input() Date: Thu, 1 Sep 2022 19:50:21 +0200 Message-Id: <20220901175022.334824-2-cezary.rojewski@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220901175022.334824-1-cezary.rojewski@intel.com> References: <20220901175022.334824-1-cezary.rojewski@intel.com> MIME-Version: 1.0 Cc: andy@kernel.org, Cezary Rojewski , kai.vehmanen@linux.intel.com, yung-chuan.liao@linux.intel.com, tiwai@suse.com, pierre-louis.bossart@linux.intel.com, willy@infradead.org, lgirdwood@gmail.com, hdegoede@redhat.com, Andy Shevchenko , ranjani.sridharan@linux.intel.com, amadeuszx.slawinski@linux.intel.com, peter.ujfalusi@linux.intel.com, linux-kernel@vger.kernel.org X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" Add new helper function to allow for splitting specified user string into a sequence of integers. Internally it makes use of get_options() so the returned sequence contains the integers extracted plus an additional element that begins the sequence and specifies the integers count. Suggested-by: Andy Shevchenko Signed-off-by: Cezary Rojewski Reviewed-by: Andy Shevchenko --- include/linux/string_helpers.h | 2 ++ lib/string_helpers.c | 45 ++++++++++++++++++++++++++++++++++ 2 files changed, 47 insertions(+) diff --git a/include/linux/string_helpers.h b/include/linux/string_helpers.h index 4d72258d42fd..97583dae556f 100644 --- a/include/linux/string_helpers.h +++ b/include/linux/string_helpers.h @@ -21,6 +21,8 @@ enum string_size_units { void string_get_size(u64 size, u64 blk_size, enum string_size_units units, char *buf, int len); +int tokenize_user_input(const char __user *from, size_t count, int **tkns); + #define UNESCAPE_SPACE BIT(0) #define UNESCAPE_OCTAL BIT(1) #define UNESCAPE_HEX BIT(2) diff --git a/lib/string_helpers.c b/lib/string_helpers.c index 5ed3beb066e6..f878afccab4c 100644 --- a/lib/string_helpers.c +++ b/lib/string_helpers.c @@ -131,6 +131,51 @@ void string_get_size(u64 size, u64 blk_size, const enum string_size_units units, } EXPORT_SYMBOL(string_get_size); +/** + * tokenize_user_input - Split string into a sequence of integers + * @from: The user space buffer to read from + * @ppos: The current position in the buffer + * @count: The maximum number of bytes to read + * @tkns: Returned pointer to sequence of integers + * + * On success @tkns is allocated and initialized with a sequence of + * integers extracted from the @from plus an additional element that + * begins the sequence and specifies the integers count. + * + * Caller takes responsibility for freeing @tkns when it is no longer + * needed. + */ +int tokenize_user_input(const char __user *from, size_t count, int **tkns) +{ + int *ints, nints; + char *buf; + int ret = 0; + + buf = memdup_user_nul(from, count); + if (IS_ERR(buf)) + return PTR_ERR(buf); + + get_options(buf, 0, &nints); + if (!nints) { + ret = -ENOENT; + goto free_buf; + } + + ints = kcalloc(nints + 1, sizeof(*ints), GFP_KERNEL); + if (!ints) { + ret = -ENOMEM; + goto free_buf; + } + + get_options(buf, nints + 1, ints); + *tkns = ints; + +free_buf: + kfree(buf); + return ret; +} +EXPORT_SYMBOL(tokenize_user_input); + static bool unescape_space(char **src, char **dst) { char *p = *dst, *q = *src;