NFS: Guard against READDIR loop when entry names exceed MAXNAMELEN
Commit 64cfca85bacd asserts the only valid return values for
nfs2/3_decode_dirent should not include -ENAMETOOLONG, but for a server
that sends a filename3 which exceeds MAXNAMELEN in a READDIR response the
client's behavior will be to endlessly retry the operation.
We could map -ENAMETOOLONG into -EBADCOOKIE, but that would produce
truncated listings without any error. The client should return an error
for this case to clearly assert that the server implementation must be
corrected.
Fixes: 64cfca85bacd ("NFS: Return valid errors from nfs2/3_decode_dirent()")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
diff --git a/fs/nfs/nfs3xdr.c b/fs/nfs/nfs3xdr.c
index 3b0b650..60f032b 100644
--- a/fs/nfs/nfs3xdr.c
+++ b/fs/nfs/nfs3xdr.c
@@ -1991,7 +1991,7 @@ int nfs3_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry,
error = decode_inline_filename3(xdr, &entry->name, &entry->len);
if (unlikely(error))
- return -EAGAIN;
+ return error == -ENAMETOOLONG ? -ENAMETOOLONG : -EAGAIN;
error = decode_cookie3(xdr, &new_cookie);
if (unlikely(error))
