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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 B5A5EC07E9A for ; Mon, 12 Jul 2021 14:21:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9386761026 for ; Mon, 12 Jul 2021 14:21:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234992AbhGLOXt (ORCPT ); Mon, 12 Jul 2021 10:23:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54742 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233949AbhGLOXs (ORCPT ); Mon, 12 Jul 2021 10:23:48 -0400 Received: from mail-wr1-x42f.google.com (mail-wr1-x42f.google.com [IPv6:2a00:1450:4864:20::42f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 43BADC0613DD; Mon, 12 Jul 2021 07:20:59 -0700 (PDT) Received: by mail-wr1-x42f.google.com with SMTP id v5so25878354wrt.3; Mon, 12 Jul 2021 07:20:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=McfcRUwTJvvEYnGyx2zdV84R9Ua8X5MJL0mSzDDl3X4=; b=CWROun1CdjvGboSFTQkv6sAppvuuPS7f/l3PB0E3owikaOeqb3QUYdUA8EKGraNI40 sGpwFUAQad1jcHO8OpB04og6pmdgnkYlGL9JvgR5MXlLbjNXFOi2U1p+EtMfBCKoh6SU bWYI8AH/ki/7khGQD1zCeWfVwMoghgNmaOOHyTki8ALhdPtYuWiKGK8zK+pFoqN8OFop yHWyshAjGPkFswLS1uYoO29xmFNEDepggh1QBrEw/Azz283rLG7S0H6RCDeuIDrPjs07 KZ2y9ISe4n+tRS4jlsiDQWyzhiCt7ZgyO+2AZ08obLfQ8e2iSTEp7XhS51tX6XGclKa/ 1ETA== 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=McfcRUwTJvvEYnGyx2zdV84R9Ua8X5MJL0mSzDDl3X4=; b=GKooTqY4zj/YN03ZPbcDdzQ8XpcjLZN5QQLJ5xuTPA20zXabMZbbhg84aWih1q1wPz +k7Q6x2aqEb//v6f0BrIGnPiaSndQUb4HIyo8u1LAnJ073K7RPa/boWkLga2CaeRoiKB rr5dMz8Ke4urjOltiaXQiypFl6Nyj2HAmwghXJC7P/PhU33I3zrZ1sNH5WK3/mozPiay 8wea57+K8Z7RnpFFBZ9bU/TvkCBw6l2TUb1o9Nxrexo7bm8KFabY2H5XtwkNJwAjCldO RHbTSN4PUJkaSowWBrb6Cq4N3ddWZXYSULKjC2l0bdWFpoSKhdGpDBL3tHqoGOFkawXJ Uynw== X-Gm-Message-State: AOAM532B+Ozujqcla8om1Vgxv2ulQqVZ1gCQ3XllaZZ/lgc4mo0LLyik TdYqGDI1f9tfBb4TrF8bhXvqyvRvAp1IgSC3Qrw= X-Google-Smtp-Source: ABdhPJyYd9ZGZO8Zy9KQ4TQfI1VbC3hvQCkAR0yvDXiUTY27zHOidGVlcOMRfd35ZqGKgtbYnT8ZTmVl+s+zu16wlMc= X-Received: by 2002:a5d:420b:: with SMTP id n11mr15661968wrq.395.1626099657917; Mon, 12 Jul 2021 07:20:57 -0700 (PDT) MIME-Version: 1.0 References: <162609463116.3133237.11899334298425929820.stgit@warthog.procyon.org.uk> <162609464716.3133237.10354897554363093252.stgit@warthog.procyon.org.uk> In-Reply-To: <162609464716.3133237.10354897554363093252.stgit@warthog.procyon.org.uk> From: Marc Dionne Date: Mon, 12 Jul 2021 11:20:47 -0300 Message-ID: Subject: Re: [PATCH 2/3] afs: check function return To: David Howells Cc: linux-afs@lists.infradead.org, Tom Rix , linux-fsdevel@vger.kernel.org, Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 12, 2021 at 9:57 AM David Howells wrote: > > From: Tom Rix > > Static analysis reports this problem > > write.c:773:29: warning: Assigned value is garbage or undefined > mapping->writeback_index = next; > ^ ~~~~ > The call to afs_writepages_region() can return without setting > next. So check the function return before using next. > > Fixes: e87b03f5830e ("afs: Prepare for use of THPs") > Signed-off-by: Tom Rix > Signed-off-by: David Howells > Link: https://lore.kernel.org/r/20210430155031.3287870-1-trix@redhat.com > --- > > fs/afs/write.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/afs/write.c b/fs/afs/write.c > index 3104b62c2082..2794147f82ff 100644 > --- a/fs/afs/write.c > +++ b/fs/afs/write.c > @@ -777,7 +777,7 @@ int afs_writepages(struct address_space *mapping, > mapping->writeback_index = next / PAGE_SIZE; Isn't there the same issue with the use of next here. > } else if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) { > ret = afs_writepages_region(mapping, wbc, 0, LLONG_MAX, &next); > - if (wbc->nr_to_write > 0) > + if (wbc->nr_to_write > 0 && ret == 0) > mapping->writeback_index = next; Unrelated to this patch, but since next is a byte offset, should this also divide by PAGE_SIZE as above. > } else { > ret = afs_writepages_region(mapping, wbc, > > Marc