From patchwork Wed May 27 14:11:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: chengkaitao X-Patchwork-Id: 11573093 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5D90D90 for ; Wed, 27 May 2020 14:12:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 458022084C for ; Wed, 27 May 2020 14:12:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Yv9N3dC8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729302AbgE0OMU (ORCPT ); Wed, 27 May 2020 10:12:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41758 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726069AbgE0OMT (ORCPT ); Wed, 27 May 2020 10:12:19 -0400 Received: from mail-pl1-x641.google.com (mail-pl1-x641.google.com [IPv6:2607:f8b0:4864:20::641]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7B457C08C5C1; Wed, 27 May 2020 07:12:19 -0700 (PDT) Received: by mail-pl1-x641.google.com with SMTP id x10so10169554plr.4; Wed, 27 May 2020 07:12:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=We66kIGMrTaCnuQtcIJQeGN/sJ3B/1sOBKzRUBIfQgA=; b=Yv9N3dC83R49iaR5Fc+lwe+9USxD9sL8CisYiRTpbUHP1OgtAF/ZZ0L04a+iLnnPWN 3hOvPreSdLy8BKaQkzOGDu/pot5wrIdFJdNBv+psJn0xBY7uTBj/kE58w56IckM/0GfI CN2CoNlebqr9KrMtITdFFw+cSWRCDqnPWNQ1h8SHqigvP0uXgOeikkA6UgKmcXSVd71s eRZ3jQzsRG4iSOEEGYDFAu3VjzxFMt8Q5VKoORPQkEqbrpaD0ss2o1+u4XB9mJnI2eCF dOBjpoSojg3jQvSjHRecP32HLF5+TROlXQprSOVmpEUcnczu4bsT9CsjvihLYx2KLBfK i/Yw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=We66kIGMrTaCnuQtcIJQeGN/sJ3B/1sOBKzRUBIfQgA=; b=NAGQZi2HRT33w4B3K6yPh9K05yFUZd+vqvzJLG5+R/nhElans4iJmoCEEHsgmNdHzz DVq/u9rRcXgR8QjDJhqwpmfcfkJvM2fC5gp+4mdfKA5fg64/HN1nQHPHui3Ua99w/hzi FwyiOvImqcEISiSWbDiIDBuaaFPf0dMaPrQ+mtFocCYiKomHqF++bBvvPmNOcSnsEvd+ +INsyJ4cW2ydy4OLPzIp+79PzFROR0YdkUhfVED9s4/q5bKOu9RCACD2cQoGbiIS0R26 g69VkYiRh3Wv2tIxH3r+Ssj2Zbl9myVVNmUNCgHKDUNCPZgIMCss1Yttha7+h371B8Vp bxlw== X-Gm-Message-State: AOAM532v9mu33qa184RwfCCcdgchAn4Q3TzWrRMnxqvOYye17OeOSpIH HOGf9HuIP9l5Vx6cFl9zvhuhgeWz X-Google-Smtp-Source: ABdhPJxC7SGcYFRflzvW2QJRicTCmgs4zKhVh4LyLSmRdyrkyLy0+S0kxreXvLSPySELQBIQMhKpfw== X-Received: by 2002:a17:90a:e30e:: with SMTP id x14mr5408544pjy.141.1590588739093; Wed, 27 May 2020 07:12:19 -0700 (PDT) Received: from Smcdef-MBP.lan ([103.136.220.66]) by smtp.gmail.com with ESMTPSA id w190sm2194684pfw.35.2020.05.27.07.12.14 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 27 May 2020 07:12:18 -0700 (PDT) From: Kaitao Cheng To: adobriyan@gmail.com Cc: christian@brauner.io, ebiederm@xmission.com, akpm@linux-foundation.org, gladkov.alexey@gmail.com, guro@fb.com, walken@google.com, avagin@gmail.com, khlebnikov@yandex-team.ru, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Kaitao Cheng Subject: [PATCH] proc/base: Skip assignment to len when there is no error on d_path in do_proc_readlink. Date: Wed, 27 May 2020 22:11:55 +0800 Message-Id: <20200527141155.47554-1-pilgrimtao@gmail.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org we don't need {len = PTR_ERR(pathname)} when IS_ERR(pathname) is false, it's better to move it into if(IS_ERR(pathname)){}. Signed-off-by: Kaitao Cheng --- fs/proc/base.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index d86c0afc8a85..9509e0d42610 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1753,9 +1753,10 @@ static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) return -ENOMEM; pathname = d_path(path, tmp, PAGE_SIZE); - len = PTR_ERR(pathname); - if (IS_ERR(pathname)) + if (IS_ERR(pathname)) { + len = PTR_ERR(pathname); goto out; + } len = tmp + PAGE_SIZE - 1 - pathname; if (len > buflen)