From patchwork Tue Jun 27 14:04:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joe Simmons-Talbott X-Patchwork-Id: 71732 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 4A047385842D for ; Tue, 27 Jun 2023 14:05:50 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 4A047385842D DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1687874750; bh=UmEMNPL8uAYehPa2Ba/ilxKjQkOpKLtwMCI3m0z37Rg=; h=To:Cc:Subject:Date:List-Id:List-Unsubscribe:List-Archive: List-Post:List-Help:List-Subscribe:From:Reply-To:From; b=AYqRGevhvDDh2SIOJT2flCwPur94y2V3UhaVD6v8LgzecczuVKI1iOcDcVyn7FsJC FZss+8twMqrYLBHgySx70Ip/DKMCKVq+FMSwTAuJGCyPtpBnIMzdQP9g7T+WLeDsyr TY1Gwqna+ZxleAGjTYApbPdkB9MblSmYAmIgpc/w= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTPS id A89133858D33 for ; Tue, 27 Jun 2023 14:05:27 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org A89133858D33 Received: from mail-qv1-f72.google.com (mail-qv1-f72.google.com [209.85.219.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-58-V780NjbxOXuou3bCjdATsQ-1; Tue, 27 Jun 2023 10:04:58 -0400 X-MC-Unique: V780NjbxOXuou3bCjdATsQ-1 Received: by mail-qv1-f72.google.com with SMTP id 6a1803df08f44-635f38834acso4722716d6.0 for ; Tue, 27 Jun 2023 07:04:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1687874673; x=1690466673; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=UmEMNPL8uAYehPa2Ba/ilxKjQkOpKLtwMCI3m0z37Rg=; b=bsW46guCiUpJApuHfOW3opb7O4x+ECV1ZO3kvHVvZkEAO6akQwFnFX/sXJTK0k4hDp gQQw7MY4Ar0xtEepqA8JD3lH87nuSQdKjpNVlhlWJLh6EzOsL+wmJzGCH0Jxvh79DdmQ j0+pPtpyVOHdFjTGOBDahF5QKb+uZUMocDU89MmWUqv8YJmBgSQgwkzYH+ts6VrJKSsk IbjF17+KbYPhwPOtmOxb4KLn4DVZiZZw35b4Ud6GQgszHACIO+eAhZiuy3n4cMj/FNfR Jn0/UZ8Lj6H4a94pziURfqbbTg8qTAyfLnnJojIM5C7NiNqHNse/0aar9I/0tX6MeB/F s47A== X-Gm-Message-State: AC+VfDxXYqulFRIz3JLjv+OPfU/n/y1F4vbyXCGB3npjNBFmfQPGAqdw scyRgaa6jT+7acsb9OISSP/edkPS2hdfzLyMCBjK9CHb3Uk5hqrLVLFGm+zJMyKzkuD1ljBcZiN bSxJuZaafJEEcrrLNRepK9Wcqnjb4K7HUqpA3F7v4aB8BN6+Imr6QgSNshNtkLr7jj0sjj4KbFR RMjYgn X-Received: by 2002:a05:6214:528b:b0:62d:ddeb:3788 with SMTP id kj11-20020a056214528b00b0062dddeb3788mr19571672qvb.38.1687874673547; Tue, 27 Jun 2023 07:04:33 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ5hmFOC0H5qYwXOPkb7H06rpA5MKdA8s5ickxKR5WEervXcBqc0Ckw5WbO4arDEKjR5qn+cQA== X-Received: by 2002:a05:6214:528b:b0:62d:ddeb:3788 with SMTP id kj11-20020a056214528b00b0062dddeb3788mr19571643qvb.38.1687874673128; Tue, 27 Jun 2023 07:04:33 -0700 (PDT) Received: from oak.redhat.com (c-71-206-142-238.hsd1.va.comcast.net. [71.206.142.238]) by smtp.gmail.com with ESMTPSA id g1-20020ac84b61000000b00402ed9adfa1sm207993qts.87.2023.06.27.07.04.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 27 Jun 2023 07:04:32 -0700 (PDT) To: libc-alpha@sourceware.org Cc: Joe Simmons-Talbott Subject: [PATCH v2] setenv.c: Get rid of alloca. Date: Tue, 27 Jun 2023 10:04:30 -0400 Message-Id: <20230627140430.3191075-1-josimmon@redhat.com> X-Mailer: git-send-email 2.40.1 MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Spam-Status: No, score=-12.5 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H5, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Joe Simmons-Talbott via Libc-alpha From: Joe Simmons-Talbott Reply-To: Joe Simmons-Talbott Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" Use malloc rather than alloca to avoid potential stack overflow. --- Changes to v1: * Use malloc since alloca'd memory is later malloc'd anyway. * Fix free logic that was breaking several testcases. stdlib/setenv.c | 42 ++++++++---------------------------------- 1 file changed, 8 insertions(+), 34 deletions(-) diff --git a/stdlib/setenv.c b/stdlib/setenv.c index ba5257d3bf..4d9848e263 100644 --- a/stdlib/setenv.c +++ b/stdlib/setenv.c @@ -44,6 +44,8 @@ extern int errno; # include #endif +#include + #if !_LIBC # define __environ environ # ifndef HAVE_ENVIRON_DECL @@ -182,18 +184,11 @@ __add_to_environ (const char *name, const char *value, const char *combined, { const size_t varlen = namelen + 1 + vallen; #ifdef USE_TSEARCH - char *new_value; - int use_alloca = __libc_use_alloca (varlen); - if (__builtin_expect (use_alloca, 1)) - new_value = (char *) alloca (varlen); - else + char *new_value = malloc (varlen); + if (new_value == NULL) { - new_value = malloc (varlen); - if (new_value == NULL) - { - UNLOCK; - return -1; - } + UNLOCK; + return -1; } # ifdef _LIBC __mempcpy (__mempcpy (__mempcpy (new_value, name, namelen), "=", 1), @@ -209,35 +204,14 @@ __add_to_environ (const char *name, const char *value, const char *combined, #endif { #ifdef USE_TSEARCH - if (__glibc_unlikely (! use_alloca)) - np = new_value; - else -#endif - { - np = malloc (varlen); - if (__glibc_unlikely (np == NULL)) - { - UNLOCK; - return -1; - } - -#ifdef USE_TSEARCH - memcpy (np, new_value, varlen); -#else - memcpy (np, name, namelen); - np[namelen] = '='; - memcpy (&np[namelen + 1], value, vallen); + np = new_value; #endif - } /* And remember the value. */ STORE_VALUE (np); } #ifdef USE_TSEARCH else - { - if (__glibc_unlikely (! use_alloca)) - free (new_value); - } + free (new_value); #endif }