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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 D0569C4338F for ; Fri, 20 Aug 2021 06:08:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A031D60FDC for ; Fri, 20 Aug 2021 06:08:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235390AbhHTGJH (ORCPT ); Fri, 20 Aug 2021 02:09:07 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:49640 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232732AbhHTGJF (ORCPT ); Fri, 20 Aug 2021 02:09:05 -0400 Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 4754021FAF; Fri, 20 Aug 2021 06:08:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1629439707; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=DzPobBwT/2VH+4sOJwojCOpyVUOdu0cJq20bNzwRRKU=; b=Voidr3lev68Q1jWFEZ+JNgbM89+3v5MNnvznqn8kZtQWZcvOnQlgdft2i5Z8PP7nzchzzH A31lMuQvoPT29pcihOVRAvqAUvb/w3wYP3z81EQTSH29j/ZPNdSAZ5p48ONR8C4D0PSEXH LEhip8bDFD9RJvMxEPi7zZNs0B3FFKA= Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap1.suse-dmz.suse.de (Postfix) with ESMTPS id 0F7CB13883; Fri, 20 Aug 2021 06:08:27 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap1.suse-dmz.suse.de with ESMTPSA id ekidANtGH2EsLgAAGKfGzw (envelope-from ); Fri, 20 Aug 2021 06:08:27 +0000 Subject: Re: [PATCH v2] btrfs: reflink: Initialize return value in btrfs_extent_same() To: Sidong Yang , linux-btrfs , David Sterba References: <20210820004100.35823-1-realwakka@gmail.com> From: Nikolay Borisov Message-ID: <6902f367-03d3-f732-5864-7c8b19a0f9e1@suse.com> Date: Fri, 20 Aug 2021 09:08:26 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210820004100.35823-1-realwakka@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 20.08.21 г. 3:41, Sidong Yang wrote: > btrfs_extent_same() cannot be called with zero length. This patch add > code that initialize ret as -EINVAL to make it safe. > > Signed-off-by: Sidong Yang Reviewed-by: Nikolay Borisov One minor nit: In this case the variable could have been initialized during definition to save 1 extra line of code. > --- > v2: > - Removed assert and added initializing ret > --- > fs/btrfs/reflink.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/fs/btrfs/reflink.c b/fs/btrfs/reflink.c > index 9b0814318e72..864f42198c5c 100644 > --- a/fs/btrfs/reflink.c > +++ b/fs/btrfs/reflink.c > @@ -653,6 +653,7 @@ static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen, > u64 i, tail_len, chunk_count; > struct btrfs_root *root_dst = BTRFS_I(dst)->root; > > + ret = -EINVAL; > spin_lock(&root_dst->root_item_lock); > if (root_dst->send_in_progress) { > btrfs_warn_rl(root_dst->fs_info, >