From patchwork Sat Jan 18 00:15:51 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gerhard Heift X-Patchwork-Id: 3507671 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 994049F39C for ; Sat, 18 Jan 2014 00:16:27 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id C86FE2017B for ; Sat, 18 Jan 2014 00:16:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DD8862017D for ; Sat, 18 Jan 2014 00:16:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752803AbaARAQY (ORCPT ); Fri, 17 Jan 2014 19:16:24 -0500 Received: from mail-ea0-f175.google.com ([209.85.215.175]:35967 "EHLO mail-ea0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752144AbaARAQV (ORCPT ); Fri, 17 Jan 2014 19:16:21 -0500 Received: by mail-ea0-f175.google.com with SMTP id z10so2020242ead.6 for ; Fri, 17 Jan 2014 16:16:20 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references; bh=aJT0QpQPjh0lVcnDluIbQ6GL1tSa6OYGozpeD7/KSjg=; b=hvGwUUX03A8duuCa3wXCcDCkjsKcb5m21poUSjvGsc55cPG4H/yJxRZob+yzUSeMnj HRnWlCJgLCEFga2jtOLB9KGbZhSBVon8YphkiS3j9iGKg1qCxxgVFxl8EAETSJoQgZqy MB68PSt9gb3qgdUomXktWy/x2JtNEQ4N4pBt8YPD2DEtmOU4K94q5NqtaGQg1svivTF1 4+43IBnXFTecKugcYsXzeoXf8pMCMUwNFfa4emvxlj3jRC3v4Ubl8E88lCMd+PRr73G4 C7kFWOX3HzoZYlLmswHiYXUSx626nMUJT8/cAJow9+mrln5SQ4GnTs65nC2ZlDfANWxh IWdQ== X-Gm-Message-State: ALoCoQlAL1B87yO9/zcG+NPGI956zZ/PskT/pwiELYOJuG43T0FSZQv8T++khTSwUfqr9MDWCsJD X-Received: by 10.14.178.130 with SMTP id f2mr4784608eem.40.1390004179453; Fri, 17 Jan 2014 16:16:19 -0800 (PST) Received: from localhost (host-115-115.kawo1.rwth-aachen.de. [134.130.115.115]) by mx.google.com with ESMTPSA id z46sm30832425een.1.2014.01.17.16.16.18 for (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Fri, 17 Jan 2014 16:16:18 -0800 (PST) From: Gerhard Heift To: linux-btrfs@vger.kernel.org Subject: [PATCH RFC 3/5] btrfs: copy_to_sk returns EOVERFLOW for too small buffer Date: Sat, 18 Jan 2014 01:15:51 +0100 Message-Id: <1390004153-4228-4-git-send-email-Gerhard@Heift.Name> X-Mailer: git-send-email 1.8.5.3 In-Reply-To: <1390004153-4228-1-git-send-email-Gerhard@Heift.Name> References: <20140116150710.GL6498@suse.cz> <1390004153-4228-1-git-send-email-Gerhard@Heift.Name> Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-7.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In copy_to_sk, if an item is too large for the given buffer, it now returns -EOVERFLOW instead of copying a search_header with len = 0. For backward compatibility for the first item it still copies such a header to the buffer, but not any other following items, which could have fitted. tree_search changes -EOVERFLOW back to 0 to behave similiar to the way it behaved before this patch. Signed-off-by: Gerhard Heift --- fs/btrfs/ioctl.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 919d928..9fa222d 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1883,8 +1883,15 @@ static noinline int copy_to_sk(struct btrfs_root *root, if (!key_in_sk(key, sk)) continue; - if (sizeof(sh) + item_len > buf_size) + if (sizeof(sh) + item_len > buf_size) { + if (*num_found) { + ret = 1; + goto overflow; + } + item_len = 0; + ret = -EOVERFLOW; + } if (sizeof(sh) + item_len + *sk_offset > buf_size) { ret = 1; @@ -1910,6 +1917,9 @@ static noinline int copy_to_sk(struct btrfs_root *root, } (*num_found)++; + if (ret) /* -EOVERFLOW from above */ + goto overflow; + if (*num_found >= sk->nr_items) break; } @@ -1990,7 +2000,8 @@ static noinline int search_ioctl(struct inode *inode, break; } - ret = 0; + if (ret > 0) + ret = 0; err: sk->nr_items = num_found; btrfs_free_path(path); @@ -2013,6 +2024,8 @@ static noinline int btrfs_ioctl_tree_search(struct file *file, inode = file_inode(file); ret = search_ioctl(inode, &args->key, sizeof(args->buf), args->buf); + if (ret == -EOVERFLOW) + ret = 0; if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) ret = -EFAULT; kfree(args);