NFS: Fix an Oops in encode_lookup()

It doesn't look as if the NFS file name limit is being initialised correctly
in the struct nfs_server. Make sure that we limit whatever is being set in
nfs_probe_fsinfo() and nfs_init_server().

Also ensure that readdirplus and nfs4_path_walk respect our file name
limits.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index ea97408e423e..e4a04d16b8b0 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1162,6 +1162,8 @@ static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc)
         }
         if (!desc->plus || !(entry->fattr->valid & NFS_ATTR_FATTR))
                 return NULL;
+        if (name.len > NFS_SERVER(dir)->namelen)
+                return NULL;
         /* Note: caller is already holding the dir->i_mutex! */
         dentry = d_alloc(parent, &name);
         if (dentry == NULL)