From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: 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 6496D3858404 for ; Thu, 1 Sep 2022 18:41:28 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 6496D3858404 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1662057688; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=nDvzLSB374cUtx18lGp8Vk532w4M0yW66T0hrcedVv8=; b=AgdsV27U1XOKSYUuLsi4OcLrhLSJrmvq3vMFd0ID0n1NAREvfodFJ9Wn4BuBMXIvA0z49a NaoicLqYdjQjmKJV9cyJUQfyetba7q/2KhKAQglm8zB6Jtxj1Jdrh67Di8SnVpQgRubuAK DaFhVx79UetV3cm9f7I9rSCBaK4tn2A= Received: from mail-yw1-f200.google.com (mail-yw1-f200.google.com [209.85.128.200]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-144-y99F6PmaOvOugIMiVN3urw-1; Thu, 01 Sep 2022 14:41:26 -0400 X-MC-Unique: y99F6PmaOvOugIMiVN3urw-1 Received: by mail-yw1-f200.google.com with SMTP id 00721157ae682-340c6cfc388so187080547b3.20 for ; Thu, 01 Sep 2022 11:41:26 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date; bh=nDvzLSB374cUtx18lGp8Vk532w4M0yW66T0hrcedVv8=; b=KpAIMqVZo+QKQnijOIAQ9B/Ysjg4Tz5essOUw5uJ49OCfTB3PmIa7bXWnBQslkMw3Q +YTqTVV6nUtXVZsdc67Ey4F9+5jx3lkirTqMeNRgoeO065MbV2AcqsqE02UdBd3Pl8X7 K5tu191OSNXe85RItOPvhUdHcec3EwBbrDBRiZLHD1WL661pz4qjQnm+gJYRrT31UxCN OBx8QvrOvaVawCGchGlxmu6kE5Ofm0h1AIRxeUx2tyn66pZXMdKYBYA9XwUdaEK5lPVo 5bwyIc1UOkf9TBzbGwW/34rwHS5UiSS538XOcuCMibLmicxy8FLQDo7RhAbnOrhrf3qJ Stmg== X-Gm-Message-State: ACgBeo3MOVzc64uOG+VGa4BHjrceZ2jEWo7turQlct6F91TkrIEXVtbg mkFE1nJRHgg8SiorLxNA+RswuCLXpb8ZSJxcRc5d9YnZOOMJf9xuRSus3Kg7eX3sLxVFoxnYNi+ nCZzDSk6YtQfvaRIpylQEkoWwSWPgX4c= X-Received: by 2002:a81:7255:0:b0:33d:d0ce:d8ce with SMTP id n82-20020a817255000000b0033dd0ced8cemr23874422ywc.239.1662057686042; Thu, 01 Sep 2022 11:41:26 -0700 (PDT) X-Google-Smtp-Source: AA6agR6b8r6/7aG857xRq1Y1dnCGPth8AmUoH6pWTY212kash7jpMpe4ISFeEvKeV8iOc2qyCk+fsT47hRZB61swPLI= X-Received: by 2002:a81:7255:0:b0:33d:d0ce:d8ce with SMTP id n82-20020a817255000000b0033dd0ced8cemr23874409ywc.239.1662057685820; Thu, 01 Sep 2022 11:41:25 -0700 (PDT) MIME-Version: 1.0 References: <20220830135625.2247198-1-torbjorn.svensson@foss.st.com> In-Reply-To: <20220830135625.2247198-1-torbjorn.svensson@foss.st.com> From: Jeff Johnston Date: Thu, 1 Sep 2022 14:41:15 -0400 Message-ID: Subject: Re: [PATCH 1/2] Used chunk needs to be removed from free_list To: =?UTF-8?Q?Torbj=C3=B6rn_SVENSSON?= Cc: Newlib X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Spam-Status: No, score=-11.1 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, HTML_MESSAGE, RCVD_IN_DNSWL_NONE, 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 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.29 X-BeenThere: newlib@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Newlib mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 01 Sep 2022 18:41:29 -0000 Patch applied. Thanks. -- Jeff J. On Tue, Aug 30, 2022 at 9:57 AM Torbj=C3=B6rn SVENSSON < torbjorn.svensson@foss.st.com> wrote: > When using nano malloc and the remaning heap space is not big enough to > fullfill the allocation, malloc will attempt to merge the last chunk in > the free list with a new allocation in order to create a bigger chunk. > This is successful, but the chunk still remains in the free_list, so > any later call to malloc can give out the same region without it first > being freed. > > Possible sequence to verify: > > void *p1 =3D malloc(3000); > void *p2 =3D malloc(4000); > void *p3 =3D malloc(5000); > void *p4 =3D malloc(6000); > void *p5 =3D malloc(7000); > free(p2); > free(p4); > void *p6 =3D malloc(35000); > free(p6); > void *p7 =3D malloc(42000); > void *p8 =3D malloc(32000); > > Without the change, p7 and p8 points to the same address. > Requirement, after malloc(35000), there is less than 42000 bytes > available on the heap. > > Contributed by STMicroelectronics > > Signed-off-by: Torbj=C3=B6rn SVENSSON > --- > newlib/libc/stdlib/nano-mallocr.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/newlib/libc/stdlib/nano-mallocr.c > b/newlib/libc/stdlib/nano-mallocr.c > index 99ad60dd0..43eb20e07 100644 > --- a/newlib/libc/stdlib/nano-mallocr.c > +++ b/newlib/libc/stdlib/nano-mallocr.c > @@ -336,6 +336,15 @@ void * nano_malloc(RARG malloc_size_t s) > if (sbrk_aligned(RCALL alloc_size) !=3D (void *)-1) > { > p->size +=3D alloc_size; > + > + /* Remove chunk from free_list */ > + r =3D free_list; > + while (r && p !=3D r->next) > + { > + r =3D r->next; > + } > + r->next =3D NULL; > + > r =3D p; > } > else > -- > 2.25.1 > >