From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f46.google.com (mail-ej1-f46.google.com [209.85.218.46]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 813D11C29 for ; Mon, 12 Sep 2022 19:01:58 +0000 (UTC) Received: by mail-ej1-f46.google.com with SMTP id go34so22417388ejc.2 for ; Mon, 12 Sep 2022 12:01:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date; bh=QL2G+Z3yBqHl6Q9wDdG1B1IyQZxcQ2fd6sZYS00IKk8=; b=KaDcDv2IbsCh9YwvPaaVG2U/f2fp5o46Sqr+Q/9I765Q4UsVSbkx+NgVnIyMCfA5r8 GM7n/rFotCqjc02mww8Aa8SImJcEARjkDvIOA/DdFfAoqeQ1zjiZp7vX2J6XJyanJrf8 Wxpz18fue/J+0g1Q8ur+rQF78OnrSVaZeu/KcvJcGeal02KLbzFZeb22NA9kTih1GJ6m qzxGzjYHINkQFywYI57mUNWEJRghsmq8qOHtCxW3rsBATM1NyMn7J0vrZfSx/mXWeHB8 XZw7XibiMrrJpofw7+leylJreHtaj1hWgsCuoLJRxFbXw5coGiuXcbCZGiXo0ISKyI5r nuVA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date; bh=QL2G+Z3yBqHl6Q9wDdG1B1IyQZxcQ2fd6sZYS00IKk8=; b=oLZzEN06xVORaBZewg8bxBcNs1urLP6Kdp7F09HYzmQjZ9LneLedPcJ5q5nHCAkpC5 YehFcOzLns0pOJcmF8sHf8fKnfxV0bgD+gHDj1vem1q2AA7yBfJOZivHOFoUmiREV/Pe NN8r53K3lVkOkLt0OHnLO/q7b/v0B9cPTXR1AkzVtJ21CkMKrTqBrRiUU8RllfDf9/XA DK+GzAerDteloJz9QrAYlnitF87aT8ElA+5MYKPtgKUzcCoktuCxhY8Ve2Iu5sDqJdPg pgxEDC8mbkPTtE761Q+aYhBYMmaTbHXeR9hZGx+AxKY3FHE75i4lKE/gkmyOi5MboCbs S7nw== X-Gm-Message-State: ACgBeo2N6UrW8/AdTupOcHZHMD06Bv157lIinSQfekHVcYHySIylVyZU rQvm/Dn85YLAYn2k+OvlAyw= X-Google-Smtp-Source: AA6agR503aOnMXLayIX0kaimdhtgCuqRgd3iWelN2bHrjINufBj8J+VIwrRT/SFXmt7/J2NhwxrVhQ== X-Received: by 2002:a17:907:c23:b0:779:237a:4218 with SMTP id ga35-20020a1709070c2300b00779237a4218mr13716539ejc.277.1663009316669; Mon, 12 Sep 2022 12:01:56 -0700 (PDT) Received: from [192.168.1.101] (p57ba2cf5.dip0.t-ipconnect.de. [87.186.44.245]) by smtp.gmail.com with ESMTPSA id l18-20020a170907915200b00722e50dab2csm4843880ejs.109.2022.09.12.12.01.55 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 12 Sep 2022 12:01:55 -0700 (PDT) Message-ID: <2b11e266-2266-b0da-3fb1-3df26236e012@gmail.com> Date: Mon, 12 Sep 2022 21:01:44 +0200 Precedence: bulk X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH] staging: vt6655: fix some erroneous memory clean-up loops Content-Language: en-US To: Nam Cao , forest@alittletooquiet.net, gregkh@linuxfoundation.org Cc: ji_hun.kim@samsung.com, dan.carpenter@oracle.com, linux-kernel@vger.kernel.org, linux-staging@lists.linux.dev References: <20220912170429.29852-1-namcaov@gmail.com> From: Philipp Hortmann In-Reply-To: <20220912170429.29852-1-namcaov@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 9/12/22 19:04, Nam Cao wrote: > In some initialization functions of this driver, memory is allocated with > 'i' acting as an index variable and increasing from 0. The commit in > "Fixes" introduces some clean-up codes in case of allocation failure, > which free memory in reverse order with 'i' decreasing to 0. However, > there are some problems: > - The case i=0 is left out. Thus memory is leaked. > - In case memory allocation fails right from the start, the memory > freeing loops will start with i=-1 and invalid memory locations will > be accessed. > > One of these loops has been fixed in commit c8ff91535880 ("staging: > vt6655: fix potential memory leak"). Fix the remaining erroneous loops. > > Link: https://lore.kernel.org/linux-staging/Yx9H1zSpxmNqx6Xc@kadam/ > Reported-by: Dan Carpenter > Fixes: 5341ee0adb17 ("staging: vt6655: check for memory allocation failures") > Signed-off-by: Nam Cao > --- > drivers/staging/vt6655/device_main.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/staging/vt6655/device_main.c b/drivers/staging/vt6655/device_main.c > index 04d737012cef..56c3cf3ba53d 100644 > --- a/drivers/staging/vt6655/device_main.c > +++ b/drivers/staging/vt6655/device_main.c > @@ -631,7 +631,7 @@ static int device_init_rd0_ring(struct vnt_private *priv) > kfree(desc->rd_info); > > err_free_desc: > - while (--i) { > + while (i--) { > desc = &priv->aRD0Ring[i]; > device_free_rx_buf(priv, desc); > kfree(desc->rd_info); > @@ -677,7 +677,7 @@ static int device_init_rd1_ring(struct vnt_private *priv) > kfree(desc->rd_info); > > err_free_desc: > - while (--i) { > + while (i--) { > desc = &priv->aRD1Ring[i]; > device_free_rx_buf(priv, desc); > kfree(desc->rd_info); > @@ -782,7 +782,7 @@ static int device_init_td1_ring(struct vnt_private *priv) > return 0; > > err_free_desc: > - while (--i) { > + while (i--) { > desc = &priv->apTD1Rings[i]; > kfree(desc->td_info); > } Tested-by: Philipp Hortmann