CRED: Pass credentials through dentry_open()

Pass credentials through dentry_open() so that the COW creds patch can have
SELinux's flush_unauthorized_files() pass the appropriate creds back to itself
when it opens its null chardev.

The security_dentry_open() call also now takes a creds pointer, as does the
dentry_open hook in struct security_operations.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: James Morris <jmorris@namei.org>

2 files changed, 4 insertions, 2 deletions

diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c
index a5e14e8695ea..632a50b4b371 100644
--- a/fs/nfsd/nfs4recover.c
+++ b/fs/nfsd/nfs4recover.c
@@ -226,7 +226,8 @@ nfsd4_list_rec_dir(struct dentry *dir, recdir_func *f)
 
         nfs4_save_user(&uid, &gid);
 
-        filp = dentry_open(dget(dir), mntget(rec_dir.mnt), O_RDONLY);
+        filp = dentry_open(dget(dir), mntget(rec_dir.mnt), O_RDONLY,
+                           current_cred());
         status = PTR_ERR(filp);
         if (IS_ERR(filp))
                 goto out;
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 890d9a68c852..b59ec5a6ed24 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -671,6 +671,7 @@ __be32
 nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
                         int access, struct file **filp)
 {
+        const struct cred *cred = current_cred();
         struct dentry   *dentry;
         struct inode    *inode;
         int             flags = O_RDONLY|O_LARGEFILE;
@@ -725,7 +726,7 @@ nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
                 DQUOT_INIT(inode);
         }
         *filp = dentry_open(dget(dentry), mntget(fhp->fh_export->ex_path.mnt),
-                                flags);
+                            flags, cred);
         if (IS_ERR(*filp))
                 host_err = PTR_ERR(*filp);
 out_nfserr: