Re: [PATCH] nfs: Fix misparsing of nfsv4 fs_locations attribute

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Should you use in4_pton() instead?

On May 9, 2008, at 4:59 PM, J. Bruce Fields wrote:

From: J. Bruce Fields <bfields@xxxxxxxxxxxxxx>

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 <bfields@xxxxxxxxxxxxxx>
---
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

--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

--
Chuck Lever
chuck[dot]lever[at]oracle[dot]com



--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Linux Filesystem Development]     [Linux USB Development]     [Linux Media Development]     [Video for Linux]     [Linux NILFS]     [Linux Audio Users]     [Yosemite Info]     [Linux SCSI]

  Powered by Linux