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 45F26C05027 for ; Sat, 21 Jan 2023 01:30:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229493AbjAUBaZ (ORCPT ); Fri, 20 Jan 2023 20:30:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38122 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229485AbjAUBaZ (ORCPT ); Fri, 20 Jan 2023 20:30:25 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 456705CE68 for ; Fri, 20 Jan 2023 17:30:24 -0800 (PST) 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 C108F620F1 for ; Sat, 21 Jan 2023 01:30:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 198DFC433EF; Sat, 21 Jan 2023 01:30:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1674264623; bh=hKI5tjJQpeVyqWhB9W2kM79wjE0/TukJ6eF4s16z9Ag=; h=Date:To:From:Subject:From; b=idN3Q7707oFiaEeLVejS5ok8z/G0AVTZDE52S8h0+R5Q9ny2qEjQhYVgRrRfWv/gA nKN1xtpdV0S16AYO46nRkqTfqkt4Vzf0QtFOEWiuNIuHGIMSAJweqYgtd9XGXkpfgG 4ksy6anBVWTmitoknKnXDLuxhbGwvRUJprY60ezw= Date: Fri, 20 Jan 2023 17:30:22 -0800 To: mm-commits@vger.kernel.org, yukuai3@huawei.com, yi.zhang@huawei.com, yangerkun@huawei.com, tj@kernel.org, james.smart@broadcom.com, jack@suse.cz, houtao1@huawei.com, ebiggers@google.com, bingjingc@synology.com, axboe@kernel.dk, lilingfeng3@huawei.com, akpm@linux-foundation.org From: Andrew Morton Subject: + lib-parser-optimize-match_number-apis-to-use-local-array.patch added to mm-nonmm-unstable branch Message-Id: <20230121013023.198DFC433EF@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: lib: parser: optimize match_NUMBER apis to use local array has been added to the -mm mm-nonmm-unstable branch. Its filename is lib-parser-optimize-match_number-apis-to-use-local-array.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/lib-parser-optimize-match_number-apis-to-use-local-array.patch This patch will later appear in the mm-nonmm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Li Lingfeng Subject: lib: parser: optimize match_NUMBER apis to use local array Date: Fri, 20 Jan 2023 11:23:52 +0800 Memory will be allocated to store substring_t in match_strdup(), which means the caller of match_strdup() may need to be scheduled out to wait for reclaiming memory. Using local array to store substring_t to remove the restriction. Link: https://lore.kernel.org/all/20221104023938.2346986-5-yukuai1@huaweicloud.com/ Link: https://lkml.kernel.org/r/20230120032352.242767-1-lilingfeng3@huawei.com Signed-off-by: Li Lingfeng Cc: BingJing Chang Cc: Eric Biggers Cc: Hou Tao Cc: James Smart Cc: Jan Kara Cc: Jens Axboe Cc: Tejun Heo Cc: yangerkun Cc: Yu Kuai Cc: Zhang Yi Signed-off-by: Andrew Morton --- --- a/lib/parser.c~lib-parser-optimize-match_number-apis-to-use-local-array +++ a/lib/parser.c @@ -11,6 +11,15 @@ #include #include +/* + * max size needed by different bases to express U64 + * HEX: "0xFFFFFFFFFFFFFFFF" --> 18 + * DEC: "18446744073709551615" --> 20 + * OCT: "01777777777777777777777" --> 23 + * pick the max one to define NUMBER_BUF_LEN + */ +#define NUMBER_BUF_LEN 24 + /** * match_one - Determines if a string matches a simple pattern * @s: the string to examine for presence of the pattern @@ -129,14 +138,12 @@ EXPORT_SYMBOL(match_token); static int match_number(substring_t *s, int *result, int base) { char *endp; - char *buf; + char buf[NUMBER_BUF_LEN]; int ret; long val; - buf = match_strdup(s); - if (!buf) - return -ENOMEM; - + if (match_strlcpy(buf, s, NUMBER_BUF_LEN) >= NUMBER_BUF_LEN) + return -ERANGE; ret = 0; val = simple_strtol(buf, &endp, base); if (endp == buf) @@ -145,7 +152,6 @@ static int match_number(substring_t *s, ret = -ERANGE; else *result = (int) val; - kfree(buf); return ret; } @@ -163,18 +169,15 @@ static int match_number(substring_t *s, */ static int match_u64int(substring_t *s, u64 *result, int base) { - char *buf; + char buf[NUMBER_BUF_LEN]; int ret; u64 val; - buf = match_strdup(s); - if (!buf) - return -ENOMEM; - + if (match_strlcpy(buf, s, NUMBER_BUF_LEN) >= NUMBER_BUF_LEN) + return -ERANGE; ret = kstrtoull(buf, base, &val); if (!ret) *result = val; - kfree(buf); return ret; } @@ -206,14 +209,12 @@ EXPORT_SYMBOL(match_int); */ int match_uint(substring_t *s, unsigned int *result) { - int err = -ENOMEM; - char *buf = match_strdup(s); + char buf[NUMBER_BUF_LEN]; - if (buf) { - err = kstrtouint(buf, 10, result); - kfree(buf); - } - return err; + if (match_strlcpy(buf, s, NUMBER_BUF_LEN) >= NUMBER_BUF_LEN) + return -ERANGE; + + return kstrtouint(buf, 10, result); } EXPORT_SYMBOL(match_uint); _ Patches currently in -mm which might be from lilingfeng3@huawei.com are lib-parser-optimize-match_number-apis-to-use-local-array.patch