From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-lj1-f174.google.com (mail-lj1-f174.google.com [209.85.208.174]) (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 D8C3D7C for ; Sun, 24 Apr 2022 19:00:14 +0000 (UTC) Received: by mail-lj1-f174.google.com with SMTP id 16so285309lju.13 for ; Sun, 24 Apr 2022 12:00:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=Ba1Aw9kjvnX8uBMGIJqvqtuzJCenFMSeGdyyYUkepxk=; b=NFnMcysY/M74wUOTLWsJ3sFRyqsdUE+AYkgczwqIpA6rDA3a+wfKXXF+YsKp6AWVNt jKC59xVvScndOiyOSQAqeq8AFPvwMod/EFfPZi6ZCg3L+JuGjbUM2Fu29yCzP5wDlWGH K0nMWgoxo1T+1cldA5F2+qyOG8X1RIldYE9q0yGmPa0qyoRbqcoNZHLoIjQ7dWZXeGeD D6U0pvddImO/Zwzm4YiDoyUh97jqszNsheMb/PJFNtBPBUGg6j8D7eyDj9cIwYVG+YFk kH3y4L9dWxKPMOhcNYnVt3lindfG+TazDXNmfvHxgyYNG6yTifwbxPL6WYaL3x1XqIbN 2ItA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=Ba1Aw9kjvnX8uBMGIJqvqtuzJCenFMSeGdyyYUkepxk=; b=sBbi8OZROR62rxIKTf4l7KboD/+IPzSsh3JjSt0jDDpjt6RiG4Xrd2HuXqZVbpCu3s TSOEsMVfsnPaumTJizzwdP8oq7ciJzzE0qDsoV+c0k7mE7NBdOTFCHKxTR80KHTbkMZD ipapQe05cyegzOBxCsaimB9ygYS8X8lDlKEp1HK+jAaHcj2b9pwLskGbiJJQSzkuvXd4 VkX23S+DcIVzrD6avs9tJR+OXcdaFQes1Pcq82IYgQVmSTGph4hjLDbuEH0Uk0ynam3h ZGB8UBSgD44AEQ9GKL8R4n8BrppwlzRIMWzUdoRwd/GoP3jSxOZZQ8b6IWltEXbaaJue +AoA== X-Gm-Message-State: AOAM533buan6CudfqiN4bhJ2m96nHGQEW90VCXtxG7rW5PMcQHA26bPN nZXCPyLfeeDWZ4iid9qW+dE= X-Google-Smtp-Source: ABdhPJzl1hVYcrCRpTkY9tsTwBZLAxRGlAQCUsllOHHecXAYYp9U31ke66oM5c4aKPk+1VzlO1zUmw== X-Received: by 2002:a2e:83c9:0:b0:24d:a95d:7b7a with SMTP id s9-20020a2e83c9000000b0024da95d7b7amr9100632ljh.254.1650826812966; Sun, 24 Apr 2022 12:00:12 -0700 (PDT) Received: from [192.168.1.11] ([94.103.225.17]) by smtp.gmail.com with ESMTPSA id f9-20020ac24989000000b0046f5d523564sm1107014lfl.84.2022.04.24.12.00.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 24 Apr 2022 12:00:11 -0700 (PDT) Message-ID: <2e4fa41d-cd06-75e4-17ac-120127fe9b2a@gmail.com> Date: Sun, 24 Apr 2022 22:00:10 +0300 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/91.7.0 Subject: Re: [PATCH 3/3] staging: r8188eu: fix null check in _rtw_free_mlme_priv Content-Language: en-US To: Vihas Makwana , Larry Finger , Phillip Potter , Greg Kroah-Hartman , Michael Straube Cc: linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org, Dan Carpenter References: <20220424163132.37007-1-makvihas@gmail.com> <20220424163132.37007-4-makvihas@gmail.com> From: Pavel Skripkin In-Reply-To: <20220424163132.37007-4-makvihas@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi Vihas, On 4/24/22 19:31, Vihas Makwana wrote: > There's a NULL check on pmlmepriv in rtw_mlme.c:112 which makes no sense > as rtw_free_mlme_priv_ie_data() dereferences it unconditionally and it > would have already crashed at this point. > Fix this by moving rtw_free_mlme_priv_ie_data() inside the check. > > Signed-off-by: Vihas Makwana That's good catch, but looks like the check is just redundant This function is called only from it's wrapper called rtw_free_mlme_priv() and rtw_free_mlme_priv() is called from 2 places: 4 drivers/staging/r8188eu/os_dep/os_intfs.c|531 col 2| rtw_free_mlme_priv(&padapter->mlmepriv); 5 drivers/staging/r8188eu/os_dep/os_intfs.c|579 col 2| rtw_free_mlme_priv(&padapter->mlmepriv); _Very_ unlikely that `&padapter->mlmepriv` expression will become NULL. > --- > drivers/staging/r8188eu/core/rtw_mlme.c | 8 +++----- > 1 file changed, 3 insertions(+), 5 deletions(-) > > diff --git a/drivers/staging/r8188eu/core/rtw_mlme.c b/drivers/staging/r8188eu/core/rtw_mlme.c > index 081c02417..87c754462 100644 > --- a/drivers/staging/r8188eu/core/rtw_mlme.c > +++ b/drivers/staging/r8188eu/core/rtw_mlme.c > @@ -109,12 +109,10 @@ void rtw_free_mlme_priv_ie_data(struct mlme_priv *pmlmepriv) > > void _rtw_free_mlme_priv(struct mlme_priv *pmlmepriv) > { > - > - rtw_free_mlme_priv_ie_data(pmlmepriv); > - > - if (pmlmepriv) > + if (pmlmepriv) { > + rtw_free_mlme_priv_ie_data(pmlmepriv); > vfree(pmlmepriv->free_bss_buf); > - > + } > } > > struct wlan_network *_rtw_alloc_network(struct mlme_priv *pmlmepriv)/* _queue *free_queue) */ With regards, Pavel Skripkin