nfsd: stop READDIRPLUS returning inconsistent attributes

The NFSv3 READDIRPLUS gets some of the returned attributes from the
readdir, and some from an inode returned from a new lookup.  The two
objects could be different thanks to intervening renames.

The attributes in READDIRPLUS are optional, so let's just skip them if
we notice this case.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 7 insertions, 5 deletions

diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c
index e4b2b4322553..f6e7cbabac5a 100644
--- a/fs/nfsd/nfs3xdr.c
+++ b/fs/nfsd/nfs3xdr.c
@@ -805,7 +805,7 @@ encode_entry_baggage(struct nfsd3_readdirres *cd, __be32 *p, const char *name,
 
 static __be32
 compose_entry_fh(struct nfsd3_readdirres *cd, struct svc_fh *fhp,
-                const char *name, int namlen)
+                 const char *name, int namlen, u64 ino)
 {
         struct svc_export       *exp;
         struct dentry           *dparent, *dchild;
@@ -830,19 +830,21 @@ compose_entry_fh(struct nfsd3_readdirres *cd, struct svc_fh *fhp,
                 goto out;
         if (d_really_is_negative(dchild))
                 goto out;
+        if (dchild->d_inode->i_ino != ino)
+                goto out;
         rv = fh_compose(fhp, exp, dchild, &cd->fh);
 out:
         dput(dchild);
         return rv;
 }
 
-static __be32 *encode_entryplus_baggage(struct nfsd3_readdirres *cd, __be32 *p, const char *name, int namlen)
+static __be32 *encode_entryplus_baggage(struct nfsd3_readdirres *cd, __be32 *p, const char *name, int namlen, u64 ino)
 {
         struct svc_fh   *fh = &cd->scratch;
         __be32 err;
 
         fh_init(fh, NFS3_FHSIZE);
-        err = compose_entry_fh(cd, fh, name, namlen);
+        err = compose_entry_fh(cd, fh, name, namlen, ino);
         if (err) {
                 *p++ = 0;
                 *p++ = 0;
@@ -927,7 +929,7 @@ encode_entry(struct readdir_cd *ccd, const char *name, int namlen,
                 p = encode_entry_baggage(cd, p, name, namlen, ino);
 
                 if (plus)
-                        p = encode_entryplus_baggage(cd, p, name, namlen);
+                        p = encode_entryplus_baggage(cd, p, name, namlen, ino);
                 num_entry_words = p - cd->buffer;
         } else if (*(page+1) != NULL) {
                 /* temporarily encode entry into next page, then move back to
@@ -941,7 +943,7 @@ encode_entry(struct readdir_cd *ccd, const char *name, int namlen,
                 p1 = encode_entry_baggage(cd, p1, name, namlen, ino);
 
                 if (plus)
-                        p1 = encode_entryplus_baggage(cd, p1, name, namlen);
+                        p1 = encode_entryplus_baggage(cd, p1, name, namlen, ino);
 
                 /* determine entry word length and lengths to go in pages */
                 num_entry_words = p1 - tmp;