NFS: Clear key construction data if the idmap upcall fails

idmap_pipe_downcall already clears this field if the upcall succeeds,
but if it fails (rpc.idmapd isn't running) the field will still be set
on the next call triggering a BUG_ON().  This patch tries to handle all
possible ways that the upcall could fail and clear the idmap key data
for each one.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Tested-by: William Dauchy <wdauchy@gmail.com>
Cc: stable@vger.kernel.org [>= 3.4]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Bryan Schumaker 2012-08-09 14:05:49 -04:00 committed by Trond Myklebust
parent cff298c721
commit c5066945b7
1 changed files with 42 additions and 14 deletions

View File

@ -61,6 +61,12 @@ struct idmap {
struct mutex idmap_mutex;
};
struct idmap_legacy_upcalldata {
struct rpc_pipe_msg pipe_msg;
struct idmap_msg idmap_msg;
struct idmap *idmap;
};
/**
* nfs_fattr_init_names - initialise the nfs_fattr owner_name/group_name fields
* @fattr: fully initialised struct nfs_fattr
@ -324,6 +330,7 @@ static ssize_t nfs_idmap_get_key(const char *name, size_t namelen,
ret = nfs_idmap_request_key(&key_type_id_resolver_legacy,
name, namelen, type, data,
data_size, idmap);
idmap->idmap_key_cons = NULL;
mutex_unlock(&idmap->idmap_mutex);
}
return ret;
@ -380,11 +387,13 @@ static const match_table_t nfs_idmap_tokens = {
static int nfs_idmap_legacy_upcall(struct key_construction *, const char *, void *);
static ssize_t idmap_pipe_downcall(struct file *, const char __user *,
size_t);
static void idmap_release_pipe(struct inode *);
static void idmap_pipe_destroy_msg(struct rpc_pipe_msg *);
static const struct rpc_pipe_ops idmap_upcall_ops = {
.upcall = rpc_pipe_generic_upcall,
.downcall = idmap_pipe_downcall,
.release_pipe = idmap_release_pipe,
.destroy_msg = idmap_pipe_destroy_msg,
};
@ -616,7 +625,8 @@ void nfs_idmap_quit(void)
nfs_idmap_quit_keyring();
}
static int nfs_idmap_prepare_message(char *desc, struct idmap_msg *im,
static int nfs_idmap_prepare_message(char *desc, struct idmap *idmap,
struct idmap_msg *im,
struct rpc_pipe_msg *msg)
{
substring_t substr;
@ -659,6 +669,7 @@ static int nfs_idmap_legacy_upcall(struct key_construction *cons,
const char *op,
void *aux)
{
struct idmap_legacy_upcalldata *data;
struct rpc_pipe_msg *msg;
struct idmap_msg *im;
struct idmap *idmap = (struct idmap *)aux;
@ -666,15 +677,15 @@ static int nfs_idmap_legacy_upcall(struct key_construction *cons,
int ret = -ENOMEM;
/* msg and im are freed in idmap_pipe_destroy_msg */
msg = kmalloc(sizeof(*msg), GFP_KERNEL);
if (!msg)
goto out0;
im = kmalloc(sizeof(*im), GFP_KERNEL);
if (!im)
data = kmalloc(sizeof(*data), GFP_KERNEL);
if (!data)
goto out1;
ret = nfs_idmap_prepare_message(key->description, im, msg);
msg = &data->pipe_msg;
im = &data->idmap_msg;
data->idmap = idmap;
ret = nfs_idmap_prepare_message(key->description, idmap, im, msg);
if (ret < 0)
goto out2;
@ -683,15 +694,15 @@ static int nfs_idmap_legacy_upcall(struct key_construction *cons,
ret = rpc_queue_upcall(idmap->idmap_pipe, msg);
if (ret < 0)
goto out2;
goto out3;
return ret;
out3:
idmap->idmap_key_cons = NULL;
out2:
kfree(im);
kfree(data);
out1:
kfree(msg);
out0:
complete_request_key(cons, ret);
return ret;
}
@ -775,9 +786,26 @@ out_incomplete:
static void
idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
{
struct idmap_legacy_upcalldata *data = container_of(msg,
struct idmap_legacy_upcalldata,
pipe_msg);
struct idmap *idmap = data->idmap;
struct key_construction *cons;
if (msg->errno) {
cons = ACCESS_ONCE(idmap->idmap_key_cons);
idmap->idmap_key_cons = NULL;
complete_request_key(cons, msg->errno);
}
/* Free memory allocated in nfs_idmap_legacy_upcall() */
kfree(msg->data);
kfree(msg);
kfree(data);
}
static void
idmap_release_pipe(struct inode *inode)
{
struct rpc_inode *rpci = RPC_I(inode);
struct idmap *idmap = (struct idmap *)rpci->private;
idmap->idmap_key_cons = NULL;
}
int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, __u32 *uid)