@@ -762,19 +762,34 @@ nfsd4_secinfo(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
__be32 err;
fh_init(&resfh, NFS4_FHSIZE);
- err = fh_verify(rqstp, &cstate->current_fh, S_IFDIR, NFSD_MAY_EXEC);
+ err = fh_verify(rqstp, &cstate->current_fh, S_IFDIR,
+ NFSD_MAY_EXEC|NFSD_MAY_BYPASS_GSS);
if (err)
return err;
+ /*
+ * XXX: arguably we should do this with elevated privileges, to
+ * ensure consistent results regardless of the cred used by the
+ * client:
+ */
err = nfsd_lookup_dentry(rqstp, &cstate->current_fh,
secinfo->si_name, secinfo->si_namelen,
&exp, &dentry);
if (err)
return err;
if (dentry->d_inode == NULL) {
+ /*
+ * An nfserr_noent return would tell the rpc caller
+ * (who may be unprivileged) that a file by that name
+ * does not exist in this directory. That may be
+ * information we don't want to give out. So return
+ * secinfo list for the parent in that case instead of
+ * failing here.
+ */
exp_put(exp);
- err = nfserr_noent;
- } else
- secinfo->si_exp = exp;
+ exp = cstate->current_fh.fh_export;
+ exp_get(exp);
+ }
+ secinfo->si_exp = exp;
dput(dentry);
if (cstate->minorversion)
/* See rfc 5661 section 2.6.3.1.1.8 */
Also planning to queue this up for 3.1.... Objections? commit ea53eb9a87848610f1a2465881d8ef6ab6c62c59 Author: J. Bruce Fields <bfields@redhat.com> Date: Wed Jun 29 18:33:11 2011 -0400 nfsd: allow secinfo to bypass gss checks PUTFH+SECINFO should succeed and return a security list even when using an authentication flavor not permitted on the given filehandle. There's the risk of a small information leak here: as part of the SECINFO, we have to do a lookup. If that lookup fails, we return the error from that lookup instead of a secinfo list. That allows an unprivileged user to answer the question "does a file named $x exist in directory $d" by guessing a filehandle for $d and then sending a secinfo request for $x and seeing whether or not they get NFS4ERR_NOENT. To avoid that, we return secinfo for the parent in the NOENT case. Reported-by: Olga Kornievskaia <aglo@citi.umich.edu> Signed-off-by: J. Bruce Fields <bfields@redhat.com> -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html