knfsd: nfsd4: return nfserr_wrongsec

Make the first actual use of the secinfo information by using it to return
nfserr_wrongsec when an export is found that doesn't allow the flavor used on
this request.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

4 files changed, 46 insertions, 0 deletions

diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index 4537a8f5cb9a..323cbdcc9bfd 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -1228,6 +1228,28 @@ exp_find(struct auth_domain *clp, int fsid_type, u32 *fsidv,
         return exp;
 }
 
+__be32 check_nfsd_access(struct svc_export *exp, struct svc_rqst *rqstp)
+{
+        struct exp_flavor_info *f;
+        struct exp_flavor_info *end = exp->ex_flavors + exp->ex_nflavors;
+
+        /* legacy gss-only clients are always OK: */
+        if (exp->ex_client == rqstp->rq_gssclient)
+                return 0;
+        /* ip-address based client; check sec= export option: */
+        for (f = exp->ex_flavors; f < end; f++) {
+                if (f->pseudoflavor == rqstp->rq_flavor)
+                        return 0;
+        }
+        /* defaults in absence of sec= options: */
+        if (exp->ex_nflavors == 0) {
+                if (rqstp->rq_flavor == RPC_AUTH_NULL ||
+                    rqstp->rq_flavor == RPC_AUTH_UNIX)
+                        return 0;
+        }
+        return nfserr_wrongsec;
+}
+
 /*
  * Uses rq_client and rq_gssclient to find an export; uses rq_client (an
  * auth_unix client) if it's available and has secinfo information;
@@ -1340,6 +1362,10 @@ exp_pseudoroot(struct svc_rqst *rqstp, struct svc_fh *fhp)
         if (IS_ERR(exp))
                 return nfserrno(PTR_ERR(exp));
         rv = fh_compose(fhp, exp, exp->ex_dentry, NULL);
+        if (rv)
+                goto out;
+        rv = check_nfsd_access(exp, rqstp);
+out:
         exp_put(exp);
         return rv;
 }
diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c
index 22cb5be79ad0..d5fe392b14fb 100644
--- a/fs/nfsd/nfsfh.c
+++ b/fs/nfsd/nfsfh.c
@@ -20,6 +20,7 @@
 
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/svc.h>
+#include <linux/sunrpc/svcauth_gss.h>
 #include <linux/nfsd/nfsd.h>
 
 #define NFSDDBG_FACILITY                NFSDDBG_FH
@@ -248,6 +249,11 @@ fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, int access)
         if (error)
                 goto out;
 
+        /* Check security flavor */
+        error = check_nfsd_access(exp, rqstp);
+        if (error)
+                goto out;
+
         /* Finally, check access permissions. */
         error = nfsd_permission(exp, dentry, access);
 
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 5c8192bcbced..a8c89ae4c743 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -494,6 +494,15 @@ out:
         module_put_and_exit(0);
 }
 
+static __be32 map_new_errors(u32 vers, __be32 nfserr)
+{
+        if (nfserr == nfserr_jukebox && vers == 2)
+                return nfserr_dropit;
+        if (nfserr == nfserr_wrongsec && vers < 4)
+                return nfserr_acces;
+        return nfserr;
+}
+
 int
 nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
 {
@@ -536,6 +545,7 @@ nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
 
         /* Now call the procedure handler, and encode NFS status. */
         nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
+        nfserr = map_new_errors(rqstp->rq_vers, nfserr);
         if (nfserr == nfserr_jukebox && rqstp->rq_vers == 2)
                 nfserr = nfserr_dropit;
         if (nfserr == nfserr_dropit) {
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 627f460a4007..8e109e586a74 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -240,6 +240,9 @@ nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
         err = nfsd_lookup_dentry(rqstp, fhp, name, len, &exp, &dentry);
         if (err)
                 return err;
+        err = check_nfsd_access(exp, rqstp);
+        if (err)
+                goto out;
         /*
          * Note: we compose the file handle now, but as the
          * dentry may be negative, it may need to be updated.
@@ -247,6 +250,7 @@ nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
         err = fh_compose(resfh, exp, dentry, fhp);
         if (!err && !dentry->d_inode)
                 err = nfserr_noent;
+out:
         dput(dentry);
         exp_put(exp);
         return err;