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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 CB1F7C432BE for ; Fri, 13 Aug 2021 17:47:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B0C8E6103A for ; Fri, 13 Aug 2021 17:47:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232186AbhHMRrn (ORCPT ); Fri, 13 Aug 2021 13:47:43 -0400 Received: from home.keithp.com ([63.227.221.253]:53698 "EHLO elaine.keithp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229919AbhHMRrm (ORCPT ); Fri, 13 Aug 2021 13:47:42 -0400 X-Greylist: delayed 515 seconds by postgrey-1.27 at vger.kernel.org; Fri, 13 Aug 2021 13:47:42 EDT Received: from localhost (localhost [127.0.0.1]) by elaine.keithp.com (Postfix) with ESMTP id 18CD23F305B7; Fri, 13 Aug 2021 10:38:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=keithp.com; s=mail; t=1628876297; bh=C899dx3Df3AlBcC6RWdM9Ct3+jWx0MfYIIh4qIowBy4=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=XNpjLFqEaE+lVTXQIyoF7fyW7xynfMQrnC+oTY140zTc2Kv7Uja9mNxoEdf4MJRNZ QsNwrwIO4PTqo5g8CN0X1/Cb4AJ9lomKgaLkaVT5dRMQ8TMfbcuSne28+KbLVMk+DH 8E6zELU5tRq+lrNB4hiGrsgxwmPAdPnlrAbXgAEskIVPVvKS1BF951kT9b7pYt7I4v GOupgWlQ6ShPfSaVSpaMOBggWnmtPW5Ys8+ScyIM96kpTpnTdwpsGtEwtQ6MesZ2u8 hwo1129wooZyg9QjrPcP/5sfXMFHtiVvNItrkJQqiRRvILUw6HAz1O1dGF/mqFH4TX O//JxFCQONEnA== X-Virus-Scanned: Debian amavisd-new at keithp.com Received: from elaine.keithp.com ([127.0.0.1]) by localhost (elaine.keithp.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id Lh7T-VbpyHUU; Fri, 13 Aug 2021 10:38:12 -0700 (PDT) Received: from keithp.com (koto.keithp.com [192.168.11.2]) by elaine.keithp.com (Postfix) with ESMTPSA id 502D13F305B6; Fri, 13 Aug 2021 10:38:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=keithp.com; s=mail; t=1628876292; bh=C899dx3Df3AlBcC6RWdM9Ct3+jWx0MfYIIh4qIowBy4=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=WMUxnb716BUu/6RWZggAojWV5Ms3XYq97jzlCiJPwldHoADb4VBLxcFjrRw2wVVuS 6aMOXrLVGGuXkOf+H+kEykM1JdyIxzge+ZvExd5WiK0kcc9D79fY6MF4m7LNA4ae6V ibGkitZWlaAqEp3Z5BIrd6Bsojjedp2/ElwxAXbupEqeKqeuqnOiehJZ3wWs+KJIC7 DKar7ZgOSLwVkxDicaUt7mwRzOx1RgIHFl7YdzHvc/t1Yj1S2ssMYjaPa4EkZGfB9d nuwz3UmHGrW352OX8jMp6FA8wcc9Yi22UBlWTsCy5oBiuTNJtaOm7wrzns/zol7T+R iWuCRRWnZuWsA== Received: by keithp.com (Postfix, from userid 1000) id 62D8C1E60119; Fri, 13 Aug 2021 10:38:34 -0700 (PDT) From: Keith Packard To: Salah Triki , Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] usb: misc: chaoskey: remove useless else In-Reply-To: <20210813164049.GA2310720@pc> References: <20210813164049.GA2310720@pc> Date: Fri, 13 Aug 2021 10:38:34 -0700 Message-ID: <87bl61utwl.fsf@keithp.com> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha256; protocol="application/pgp-signature" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-=-= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable Salah Triki writes: > Remove useless else in order to make the code cleaner. > - if (!dev->present) { > - if (dev->open =3D=3D 0) { > - mutex_unlock(&dev->lock); > + mutex_unlock(&dev->lock); > + > + if (!dev->present) > + if (dev->open =3D=3D 0) > chaoskey_free(dev); > - } else > - mutex_unlock(&dev->lock); > - } else > - mutex_unlock(&dev->lock); This accesses dev->present outside of the lock region introducing a potential race condition. =2D-=20 =2Dkeith --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEw4O3eCVWE9/bQJ2R2yIaaQAAABEFAmEWrhoACgkQ2yIaaQAA ABGrbQ/+O0U3SxZLR2Hizm26TbH06UsEA5Mx4futZ23knkILxyPzMwSDeR2HFOTM ZrYOSgs+1aTKW5a3rHbQQMMB8btXuyORcZTLwJCRrbIXX4O7vQbzdT9+iuPUqbbd tlOleHpZLCCQipK3MUV02tpN+UH7IQ4UxmONjpLvFQBBA0mqNichpZ1Q0P2px4W8 ecjz4rS+jES3iLZLbQHkhLx37wePDzavUJ++yxDKlJ798PHfN6Jhint8W25IpyQ6 iaJdagoC6Xxo1IGXp+XJepu0PcqVTox4akS15PGhMQ7Kgdn9N5s3Bmv8QQ5JgjL3 DMFEt3hSmxdnZtFGbq++L4NS6s0Fmds21Da9zj4yZ3XKZ3vVkOsF/lXDOrdnmiVD KwhtYqz3zbf0mTd4vUbnym6wTCONYnOb/hEahu6DFJL3wbC/NxvIIn7L68DgOHzC 7WTyfdqOkAeFPRY4oIxOQLCdDf3Q5hD9k9VOj9ymkL1iKbx5bcw+0g+5e145e4yG f/in1d6EormuSTWyEwgMGDGxXEUHXJyHEqMBuXXtoeySIeEKXl8fzQAezDqxnh0J b4irU4usWAA2+BuNxZ/bfaKrrRqWBDsWJt8oKaNrRaTeaPSFvtBfG6iAjndqm4oq erMg5gpd6r0jd+44IBKHoIVRjT76n8+3PxxqYPlVctAvUMLX3NQ= =GgHp -----END PGP SIGNATURE----- --=-=-=--