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 X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9F95FC4320E for ; Wed, 1 Sep 2021 18:54:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8C5C260F11 for ; Wed, 1 Sep 2021 18:54:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245572AbhIASzW (ORCPT ); Wed, 1 Sep 2021 14:55:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244827AbhIASzP (ORCPT ); Wed, 1 Sep 2021 14:55:15 -0400 Received: from mail-qk1-x736.google.com (mail-qk1-x736.google.com [IPv6:2607:f8b0:4864:20::736]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 90FF1C061575 for ; Wed, 1 Sep 2021 11:54:17 -0700 (PDT) Received: by mail-qk1-x736.google.com with SMTP id a10so508529qka.12 for ; Wed, 01 Sep 2021 11:54:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=itfac-mrt-ac-lk.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=yACBHeKeTEMDk9G3lLdGdDWvtaeZqYr0jQBUvqwglB4=; b=Idwyh/ZOPXWdXddScG9pysT9Y1D20q4/aaYdSHfPuGvxdq8UBrqgS0gGKzb2RyhlFG 1ixEQaGyJhPCSvAIC9kVBRrsdpYew405vHVNIMYDMr2eCGTJT5aNsIennOISX/1fSbLB vw0hxgb9xxUjp5BnURN8EsrzaTSVLcoqF18z4bqyAsWyeb4EZJdmVa1YIGjA5BKRW83M c+R0ypRvgnYpol8jKW5URb6aIZ8R57CHUt66XSfw2GJe6RwKawG6pI8KBuT8dzCDAY1T ++89cqPwwX4CefMn1INBz7ULDzTtB40xZ344utxHy1zRKa9QDMKQxLlZ87RofmhBTNE5 f3bA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=yACBHeKeTEMDk9G3lLdGdDWvtaeZqYr0jQBUvqwglB4=; b=d1wsJVDhpTEq/mik40CQPJNTUyIduBYzblY44mufdi4jAQDyvgy1dZ4b0Ksb3BldsZ nM6GUH/KOmpBbjGBHOttZfXq5Fw3tangxi/+XIAvIYbxpywikDRmAchCGJ6eKC92sHkp 7U9YZwuKSBFKu0bab+gHemF/qOs5pWM07zE1samJ9d66Vq4xQRrLqfEQPG7QMnfXgt9A tz3xGL9SL9Ev+Uq4Shixq5Sd7VR2x7fbxsUjlKCPfIvoIjpV3/fj0eTuWpr/DspRHNf4 fS6nnN/htKmX/OZPC+gXvcqzKh9qEnr6T5VdEMtEqxf9b2P2qdC4EU/2Hj6F2BrnSYgn YpAg== X-Gm-Message-State: AOAM530tpd8MKcNPs0oyhF2Aid+ytNwzsiEKYXV+Ys0haH83vTBKHdUQ bh2Mv3EC0ntUS3HlAFApPK2bzY7oSdV8VTZATRmRy5FcgwaV X-Google-Smtp-Source: ABdhPJwxUAWGvA4IBMn5mMg38sMi31Mre6YzUnRruh8cQT7hDfLAJ8Qn5kmdWmS5DDnWKzNCtLE9LtF6dBqjhJRtPZ8= X-Received: by 2002:a05:620a:1379:: with SMTP id d25mr1128331qkl.238.1630522456666; Wed, 01 Sep 2021 11:54:16 -0700 (PDT) MIME-Version: 1.0 References: <20210830193355.11338-1-asha.16@itfac.mrt.ac.lk> <20210831084735.GL12231@kadam> In-Reply-To: <20210831084735.GL12231@kadam> From: "F.A. SULAIMAN" Date: Thu, 2 Sep 2021 00:24:05 +0530 Message-ID: Subject: Re: [PATCH] staging: rtl8723bs: fix memory leak error To: Dan Carpenter Cc: Greg KH , devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 31, 2021 at 2:18 PM Dan Carpenter wrote: > > On Tue, Aug 31, 2021 at 01:03:55AM +0530, F.A.Sulaiman wrote: > > Smatch reported memory leak bug in rtl8723b_FirmwareDownload function. > > The problem is pFirmware memory is not released in release_fw1. > > Instead of redirecting to release_fw1 we can turn it into exit > > and free the memory. > > > > Signed-off-by: F.A. SULAIMAN > > --- > > drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c | 3 +-- > > 1 file changed, 1 insertion(+), 2 deletions(-) > > > > diff --git a/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c b/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c > > index de8caa6cd418..b59c2aa3a9d8 100644 > > --- a/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c > > +++ b/drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c > > @@ -436,7 +436,7 @@ s32 rtl8723b_FirmwareDownload(struct adapter *padapter, bool bUsedWoWLANFw) > > if (pFirmware->fw_length > FW_8723B_SIZE) { > > rtStatus = _FAIL; > > DBG_871X_LEVEL(_drv_emerg_, "Firmware size:%u exceed %u\n", pFirmware->fw_length, FW_8723B_SIZE); > > - goto release_fw1; > > + goto exit; > > } > > The current tree doesn't have DBG_871X_LEVEL() so you must be working > against something old. You need to work against linux-next or staging > next. > > Your patch fixes a bug, but it would be better to just re-write the > error handling for this function. There is another bug that a bunch > of error paths don't call release_firmware(fw). Use the "Free the Last > Thing" method. > > pFirmware = kzalloc(sizeof(struct rt_firmware), GFP_KERNEL); > if (!pFirmware) > return _FAIL; > > The last thing we allocated is "pFirmware" so free that if we have an > error. > > pBTFirmware = kzalloc(sizeof(struct rt_firmware), GFP_KERNEL); > if (!pBTFirmware) { > rtStatus = _FAIL; > goto free_firmware; > } > > Now the last thing is pBTFirmware. > > rtStatus = request_firmware(&fw, fwfilepath, device); > if (rtStatus) { > rtStatus = _FAIL; > goto free_bt_firmware; > } > > Now the last thing is "fw". But this is a bit tricky because we're > going to release it as soon as possible and not wait until the end of > the function. There isn't a reason for this... We can change that or > keep it as-is. If we keep it as is, then the we'll just call > release_firmware(fw); before the goto free_bt_firmware; The current > code leaks fw on a bunch of error paths. > > pFirmware->fw_buffer_sz = kmemdup(fw->data, fw->size, GFP_KERNEL); > if (!pFirmware->fw_buffer_sz) { > rtStatus = _FAIL; > release_firmware(fw); > goto free_bt_firmware; > } > > Or: > > pFirmware->fw_buffer_sz = kmemdup(fw->data, fw->size, GFP_KERNEL); > if (!pFirmware->fw_buffer_sz) { > rtStatus = _FAIL; > goto release_fw; > } > > Now the last thing is pFirmware->fw_buffer_sz. Etc. > > Then at the end it's just: > > free_fw_buffer: > kfree(pFirmware->fw_buffer_sz); > release_fw: > release_firmware(fw); > free_bt_firmware: > kfree(pBTFirmware); > free_firmware: > kfree(pFirmware); > > return rtStatus; > } > Thank you! I'll do the changes and send you a v2 patch. Best Regards, Asha Sulaiman.