From mboxrd@z Thu Jan 1 00:00:00 1970 From: Niu Subject: e2fsprogs: Avoid infinite loop in ext2fs_find_block_device() Date: Thu, 03 Nov 2011 14:45:29 +0800 Message-ID: <4EB23889.1010807@whamcloud.com> Mime-Version: 1.0 Content-Type: text/plain; charset=GB2312 Content-Transfer-Encoding: 7bit Cc: linux-ext4@vger.kernel.org To: tytso@mit.edu Return-path: Received: from mail-iy0-f174.google.com ([209.85.210.174]:33900 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752572Ab1KCGqi (ORCPT ); Thu, 3 Nov 2011 02:46:38 -0400 Received: by iage36 with SMTP id e36so994858iag.19 for ; Wed, 02 Nov 2011 23:46:37 -0700 (PDT) Sender: linux-ext4-owner@vger.kernel.org List-ID: hello, Ted In my rhel5 system, there are lots of loop links in the /dev/.udev/failed folder, which makes the e2fsprogs 'make check' stuck in 't_ext_jnl_rm'. I'm not sure if the loop links are generated by udev defect or misconfiguration, but anyway, I think the ext2fs_find_block_device() should do some sanity check to avoid infinite loop. I made a simple patch which breaks the loop when depth reaching 5 in ext2fs_find_block_device(), any comments? Thank you. >>From 5ef3b82266e7fb5edbce4febc4924b0beaccacf1 Mon Sep 17 00:00:00 2001 From: Niu Yawei Date: Wed, 2 Nov 2011 04:31:11 +0800 Subject: [PATCH] Avoid infinite loop in ext2fs_find_block_device() The ext2fs_find_block_device() should stop searching when the directory depth reaching a certain threshold, otherwise, it could run into infinite loop if there are loop links in the device directory. Signed-off-by: Niu Yawei --- lib/ext2fs/finddev.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/lib/ext2fs/finddev.c b/lib/ext2fs/finddev.c index 13ef14b..61f9754 100644 --- a/lib/ext2fs/finddev.c +++ b/lib/ext2fs/finddev.c @@ -128,6 +128,7 @@ char *ext2fs_find_block_device(dev_t device) struct dir_list *list = 0, *new_list = 0; struct dir_list *current; char *ret_path = 0; + int level = 0; /* * Add the starting directories to search... @@ -154,6 +155,9 @@ char *ext2fs_find_block_device(dev_t device) if (list == 0) { list = new_list; new_list = 0; + /* Avoid infinite loop */ + if (++level > 5) + break; } } free_dirlist(&list); -- 1.7.1