NFSv4: Ensure that idmap_pipe_downcall sanity-checks the downcall data
Use the idmapper upcall data to verify that the legacy idmapper daemon
is indeed responding to an upcall that we sent.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Bryan Schumaker <bjschuma@netapp.com>
diff --git a/fs/nfs/idmap.c b/fs/nfs/idmap.c
index 8222ad8..7ac93e0 100644
--- a/fs/nfs/idmap.c
+++ b/fs/nfs/idmap.c
@@ -55,18 +55,19 @@
static const struct cred *id_resolver_cache;
static struct key_type key_type_id_resolver_legacy;
-struct idmap {
- struct rpc_pipe *idmap_pipe;
- struct key_construction *idmap_key_cons;
- struct mutex idmap_mutex;
-};
-
struct idmap_legacy_upcalldata {
struct rpc_pipe_msg pipe_msg;
struct idmap_msg idmap_msg;
+ struct key_construction *key_cons;
struct idmap *idmap;
};
+struct idmap {
+ struct rpc_pipe *idmap_pipe;
+ struct idmap_legacy_upcalldata *idmap_upcall_data;
+ struct mutex idmap_mutex;
+};
+
/**
* nfs_fattr_init_names - initialise the nfs_fattr owner_name/group_name fields
* @fattr: fully initialised struct nfs_fattr
@@ -663,29 +664,30 @@
static bool
nfs_idmap_prepare_pipe_upcall(struct idmap *idmap,
- struct key_construction *cons)
+ struct idmap_legacy_upcalldata *data)
{
- if (idmap->idmap_key_cons != NULL) {
+ if (idmap->idmap_upcall_data != NULL) {
WARN_ON_ONCE(1);
return false;
}
- idmap->idmap_key_cons = cons;
+ idmap->idmap_upcall_data = data;
return true;
}
static void
nfs_idmap_complete_pipe_upcall_locked(struct idmap *idmap, int ret)
{
- struct key_construction *cons = idmap->idmap_key_cons;
+ struct key_construction *cons = idmap->idmap_upcall_data->key_cons;
- idmap->idmap_key_cons = NULL;
+ kfree(idmap->idmap_upcall_data);
+ idmap->idmap_upcall_data = NULL;
complete_request_key(cons, ret);
}
static void
nfs_idmap_abort_pipe_upcall(struct idmap *idmap, int ret)
{
- if (idmap->idmap_key_cons != NULL)
+ if (idmap->idmap_upcall_data != NULL)
nfs_idmap_complete_pipe_upcall_locked(idmap, ret);
}
@@ -714,14 +716,12 @@
goto out2;
ret = -EAGAIN;
- if (!nfs_idmap_prepare_pipe_upcall(idmap, cons))
+ if (!nfs_idmap_prepare_pipe_upcall(idmap, data))
goto out2;
ret = rpc_queue_upcall(idmap->idmap_pipe, msg);
- if (ret < 0) {
+ if (ret < 0)
nfs_idmap_abort_pipe_upcall(idmap, ret);
- kfree(data);
- }
return ret;
out2:
@@ -738,21 +738,32 @@
authkey);
}
-static int nfs_idmap_read_message(struct idmap_msg *im, struct key *key, struct key *authkey)
+static int nfs_idmap_read_and_verify_message(struct idmap_msg *im,
+ struct idmap_msg *upcall,
+ struct key *key, struct key *authkey)
{
char id_str[NFS_UINT_MAXLEN];
- int ret = -EINVAL;
+ int ret = -ENOKEY;
+ /* ret = -ENOKEY */
+ if (upcall->im_type != im->im_type || upcall->im_conv != im->im_conv)
+ goto out;
switch (im->im_conv) {
case IDMAP_CONV_NAMETOID:
+ if (strcmp(upcall->im_name, im->im_name) != 0)
+ break;
sprintf(id_str, "%d", im->im_id);
ret = nfs_idmap_instantiate(key, authkey, id_str);
break;
case IDMAP_CONV_IDTONAME:
+ if (upcall->im_id != im->im_id)
+ break;
ret = nfs_idmap_instantiate(key, authkey, im->im_name);
break;
+ default:
+ ret = -EINVAL;
}
-
+out:
return ret;
}
@@ -770,10 +781,11 @@
* will have been woken up and someone else may now have used
* idmap_key_cons - so after this point we may no longer touch it.
*/
- cons = idmap->idmap_key_cons;
- if (cons == NULL)
+ if (idmap->idmap_upcall_data == NULL)
goto out_noupcall;
+ cons = idmap->idmap_upcall_data->key_cons;
+
if (mlen != sizeof(im)) {
ret = -ENOSPC;
goto out;
@@ -793,9 +805,11 @@
if (namelen_in == 0 || namelen_in == IDMAP_NAMESZ) {
ret = -EINVAL;
goto out;
- }
+}
- ret = nfs_idmap_read_message(&im, cons->key, cons->authkey);
+ ret = nfs_idmap_read_and_verify_message(&im,
+ &idmap->idmap_upcall_data->idmap_msg,
+ cons->key, cons->authkey);
if (ret >= 0) {
key_set_timeout(cons->key, nfs_idmap_cache_timeout);
ret = mlen;
@@ -817,8 +831,6 @@
if (msg->errno)
nfs_idmap_abort_pipe_upcall(idmap, msg->errno);
- /* Free memory allocated in nfs_idmap_legacy_upcall() */
- kfree(data);
}
static void