On Mon, 13 Aug 2012 15:37:31 +0400 Stanislav Kinsbursky <skinsbursky@xxxxxxxxxxxxx> wrote: > v2: > 1) rpc_clnt_set_nodename() prototype updated. > 2) fixed errors in comment. > > When child reaper exits, it can destroy mount namespace it belongs to, and if > there are NFS mounts inside, then it will try to umount them. But in this > point current->nsproxy is set to NULL and all namespaces will be destroyed one > by one. I.e. we can't dereference current->nsproxy to obtain uts namespace. > > Signed-off-by: Stanislav Kinsbursky <skinsbursky@xxxxxxxxxxxxx> > --- > net/sunrpc/clnt.c | 16 +++++++++++++--- > 1 files changed, 13 insertions(+), 3 deletions(-) > > diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c > index 9a9676e..8fbcbc8 100644 > --- a/net/sunrpc/clnt.c > +++ b/net/sunrpc/clnt.c > @@ -277,8 +277,18 @@ void rpc_clients_notifier_unregister(void) > return rpc_pipefs_notifier_unregister(&rpc_clients_block); > } > > -static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename) > +static void rpc_clnt_set_nodename(struct rpc_clnt *clnt) > { > + const char *nodename; > + > + /* > + * We have to protect against dying child reaper, which has released > + * its nsproxy already and is trying to destroy mount namespace. > + */ > + if (current->nsproxy == NULL) > + return; > + > + nodename = utsname()->nodename; > clnt->cl_nodelen = strlen(nodename); > if (clnt->cl_nodelen > UNX_MAXNODENAME) > clnt->cl_nodelen = UNX_MAXNODENAME; > @@ -365,7 +375,7 @@ static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, stru > } > > /* save the nodename */ > - rpc_clnt_set_nodename(clnt, utsname()->nodename); > + rpc_clnt_set_nodename(clnt); > rpc_register_client(clnt); > return clnt; > > @@ -524,7 +534,7 @@ rpc_clone_client(struct rpc_clnt *clnt) > err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name); > if (err != 0) > goto out_no_path; > - rpc_clnt_set_nodename(new, utsname()->nodename); > + rpc_clnt_set_nodename(new); > if (new->cl_auth) > atomic_inc(&new->cl_auth->au_count); > atomic_inc(&clnt->cl_count); > > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html Acked-by: Jeff Layton <jlayton@xxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html