mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 08:19:28 +00:00
SUNRPC: Fix races in rpcauth_create
See the FIXME: auth_flavors[] really needs a lock and module refcounting. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
parent
07a2bf1da4
commit
fc1b356f56
1 changed files with 24 additions and 11 deletions
|
@ -18,6 +18,7 @@
|
|||
# define RPCDBG_FACILITY RPCDBG_AUTH
|
||||
#endif
|
||||
|
||||
static DEFINE_SPINLOCK(rpc_authflavor_lock);
|
||||
static struct rpc_authops * auth_flavors[RPC_AUTH_MAXFLAVOR] = {
|
||||
&authnull_ops, /* AUTH_NULL */
|
||||
&authunix_ops, /* AUTH_UNIX */
|
||||
|
@ -35,26 +36,34 @@ int
|
|||
rpcauth_register(struct rpc_authops *ops)
|
||||
{
|
||||
rpc_authflavor_t flavor;
|
||||
int ret = -EPERM;
|
||||
|
||||
if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
|
||||
return -EINVAL;
|
||||
if (auth_flavors[flavor] != NULL)
|
||||
return -EPERM; /* what else? */
|
||||
auth_flavors[flavor] = ops;
|
||||
return 0;
|
||||
spin_lock(&rpc_authflavor_lock);
|
||||
if (auth_flavors[flavor] == NULL) {
|
||||
auth_flavors[flavor] = ops;
|
||||
ret = 0;
|
||||
}
|
||||
spin_unlock(&rpc_authflavor_lock);
|
||||
return ret;
|
||||
}
|
||||
|
||||
int
|
||||
rpcauth_unregister(struct rpc_authops *ops)
|
||||
{
|
||||
rpc_authflavor_t flavor;
|
||||
int ret = -EPERM;
|
||||
|
||||
if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
|
||||
return -EINVAL;
|
||||
if (auth_flavors[flavor] != ops)
|
||||
return -EPERM; /* what else? */
|
||||
auth_flavors[flavor] = NULL;
|
||||
return 0;
|
||||
spin_lock(&rpc_authflavor_lock);
|
||||
if (auth_flavors[flavor] == ops) {
|
||||
auth_flavors[flavor] = NULL;
|
||||
ret = 0;
|
||||
}
|
||||
spin_unlock(&rpc_authflavor_lock);
|
||||
return ret;
|
||||
}
|
||||
|
||||
struct rpc_auth *
|
||||
|
@ -68,15 +77,19 @@ rpcauth_create(rpc_authflavor_t pseudoflavor, struct rpc_clnt *clnt)
|
|||
if (flavor >= RPC_AUTH_MAXFLAVOR)
|
||||
goto out;
|
||||
|
||||
/* FIXME - auth_flavors[] really needs an rw lock,
|
||||
* and module refcounting. */
|
||||
#ifdef CONFIG_KMOD
|
||||
if ((ops = auth_flavors[flavor]) == NULL)
|
||||
request_module("rpc-auth-%u", flavor);
|
||||
#endif
|
||||
if ((ops = auth_flavors[flavor]) == NULL)
|
||||
spin_lock(&rpc_authflavor_lock);
|
||||
ops = auth_flavors[flavor];
|
||||
if (ops == NULL || !try_module_get(ops->owner)) {
|
||||
spin_unlock(&rpc_authflavor_lock);
|
||||
goto out;
|
||||
}
|
||||
spin_unlock(&rpc_authflavor_lock);
|
||||
auth = ops->create(clnt, pseudoflavor);
|
||||
module_put(ops->owner);
|
||||
if (IS_ERR(auth))
|
||||
return auth;
|
||||
if (clnt->cl_auth)
|
||||
|
|
Loading…
Reference in a new issue