From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sunil Mushran Date: Mon, 12 Jul 2010 16:46:59 +0000 Subject: Re: [patch] ocfs2: tighten up strlen() checking Message-Id: <4C3B4703.2000902@oracle.com> List-Id: References: <20100710143336.GB19184@bicker> In-Reply-To: <20100710143336.GB19184@bicker> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ocfs2-devel@oss.oracle.com Acked-by: Sunil Mushran On 07/10/2010 07:33 AM, Dan Carpenter wrote: > This function is only called from one place and it's like this: > dlm_register_domain(conn->cc_name, dlm_key,&fs_version); > > The "conn->cc_name" is 64 characters long. If strlen(conn->cc_name) > were equal to O2NM_MAX_NAME_LEN (64) that would be a bug because > strlen() doesn't count the NULL character. > > In fact, if you look how O2NM_MAX_NAME_LEN is used, it mostly describes > 64 character buffers. The only exception is nd_name from struct > o2nm_node. > > Anyway I looked into it and in this case the domain string comes from > osb->uuid_str in ocfs2_setup_osb_uuid(). That's 32 characters and NULL > which easily fits into O2NM_MAX_NAME_LEN. This patch doesn't change how > the code works, but I think it makes the code a little cleaner. > > Signed-off-by: Dan Carpenter > --- > Or we could get rid of check entirely. > > diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c > index 6b5a492..084b051 100644 > --- a/fs/ocfs2/dlm/dlmdomain.c > +++ b/fs/ocfs2/dlm/dlmdomain.c > @@ -1671,7 +1671,7 @@ struct dlm_ctxt * dlm_register_domain(const char *domain, > struct dlm_ctxt *dlm = NULL; > struct dlm_ctxt *new_ctxt = NULL; > > - if (strlen(domain)> O2NM_MAX_NAME_LEN) { > + if (strlen(domain)>= O2NM_MAX_NAME_LEN) { > ret = -ENAMETOOLONG; > mlog(ML_ERROR, "domain name length too long\n"); > goto leave; >