From: "J. Bruce Fields" Subject: [PATCH] nfs: Fix misparsing of nfsv4 fs_locations attribute Date: Fri, 9 May 2008 19:59:30 -0400 Message-ID: <20080509235930.GM1907@fieldses.org> References: <20080509011918.GK12690@fieldses.org> <1210309839.8657.0.camel@localhost> <20080509152750.GA325@fieldses.org> <20080509165204.GB1907@fieldses.org> <20080509171208.GC1907@fieldses.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Trond Myklebust , linux-nfs@vger.kernel.org, Manoj Naik To: Trond Myklebust Return-path: Received: from mail.fieldses.org ([66.93.2.214]:49537 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756638AbYEIX7i (ORCPT ); Fri, 9 May 2008 19:59:38 -0400 In-Reply-To: <20080509171208.GC1907@fieldses.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: From: J. Bruce Fields The code incorrectly assumes here that the server name (or ip address) is null-terminated. This can cause referrals to fail in some cases. Signed-off-by: J. Bruce Fields --- fs/nfs/nfs4namespace.c | 12 +++++++++--- 1 files changed, 9 insertions(+), 3 deletions(-) I think this was the bug causing the referral failures. There must be a less ugly solution, though. --b. diff --git a/fs/nfs/nfs4namespace.c b/fs/nfs/nfs4namespace.c index 5f9ba41..2684c65 100644 --- a/fs/nfs/nfs4namespace.c +++ b/fs/nfs/nfs4namespace.c @@ -96,11 +96,17 @@ static int nfs4_validate_fspath(const struct vfsmount *mnt_parent, /* * Check if the string represents a "valid" IPv4 address */ -static inline int valid_ipaddr4(const char *buf) +static inline int valid_ipaddr4(const struct nfs4_string *buf) { int rc, count, in[4]; - rc = sscanf(buf, "%d.%d.%d.%d", &in[0], &in[1], &in[2], &in[3]); + /* + * XXX: Depending on the knowledge that the following byte is + * either xdr padding or an xdr length that has already been + * copied: + */ + buf->data[buf->len] = '\0'; + rc = sscanf(buf->data, "%d.%d.%d.%d", &in[0], &in[1], &in[2], &in[3]); if (rc != 4) return -EINVAL; for (count = 0; count < 4; count++) { @@ -178,7 +184,7 @@ static struct vfsmount *nfs_follow_referral(const struct vfsmount *mnt_parent, }; if (location->servers[s].len <= 0 || - valid_ipaddr4(location->servers[s].data) < 0) { + valid_ipaddr4(&location->servers[s]) < 0) { s++; continue; } -- 1.5.5.rc1