diff options
| -rw-r--r-- | include/linux/nsproxy.h | 30 | ||||
| -rw-r--r-- | kernel/exit.c | 6 | ||||
| -rw-r--r-- | kernel/fork.c | 4 | ||||
| -rw-r--r-- | kernel/nsproxy.c | 16 |
4 files changed, 40 insertions, 16 deletions
diff --git a/include/linux/nsproxy.h b/include/linux/nsproxy.h index 0b9f0dc30d61..678e1d38effb 100644 --- a/include/linux/nsproxy.h +++ b/include/linux/nsproxy.h @@ -35,22 +35,30 @@ struct nsproxy *dup_namespaces(struct nsproxy *orig); int copy_namespaces(int flags, struct task_struct *tsk); void get_task_namespaces(struct task_struct *tsk); void free_nsproxy(struct nsproxy *ns); +struct nsproxy *put_nsproxy(struct nsproxy *ns); -static inline void put_nsproxy(struct nsproxy *ns) +static inline void finalize_put_nsproxy(struct nsproxy *ns) { - if (atomic_dec_and_test(&ns->count)) { + if (ns) free_nsproxy(ns); - } } -static inline void exit_task_namespaces(struct task_struct *p) +static inline void put_and_finalize_nsproxy(struct nsproxy *ns) { - struct nsproxy *ns = p->nsproxy; - if (ns) { - task_lock(p); - p->nsproxy = NULL; - task_unlock(p); - put_nsproxy(ns); - } + finalize_put_nsproxy(put_nsproxy(ns)); +} + +static inline struct nsproxy *preexit_task_namespaces(struct task_struct *p) +{ + return put_nsproxy(p->nsproxy); +} + +static inline void exit_task_namespaces(struct task_struct *p, + struct nsproxy *ns) +{ + task_lock(p); + p->nsproxy = NULL; + task_unlock(p); + finalize_put_nsproxy(ns); } #endif diff --git a/kernel/exit.c b/kernel/exit.c index 35401720635b..a5bf5329ff97 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -396,7 +396,7 @@ void daemonize(const char *name, ...) current->fs = fs; atomic_inc(&fs->count); - exit_task_namespaces(current); + put_and_finalize_nsproxy(current->nsproxy); current->nsproxy = init_task.nsproxy; get_task_namespaces(current); @@ -853,6 +853,7 @@ static void exit_notify(struct task_struct *tsk) fastcall NORET_TYPE void do_exit(long code) { struct task_struct *tsk = current; + struct nsproxy *ns; int group_dead; profile_task_exit(tsk); @@ -938,8 +939,9 @@ fastcall NORET_TYPE void do_exit(long code) tsk->exit_code = code; proc_exit_connector(tsk); + ns = preexit_task_namespaces(tsk); exit_notify(tsk); - exit_task_namespaces(tsk); + exit_task_namespaces(tsk, ns); #ifdef CONFIG_NUMA mpol_free(tsk->mempolicy); tsk->mempolicy = NULL; diff --git a/kernel/fork.c b/kernel/fork.c index fc723e595cd5..4cf868458f06 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1265,7 +1265,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, return p; bad_fork_cleanup_namespaces: - exit_task_namespaces(p); + put_and_finalize_nsproxy(p->nsproxy); bad_fork_cleanup_keys: exit_keys(p); bad_fork_cleanup_mm: @@ -1711,7 +1711,7 @@ asmlinkage long sys_unshare(unsigned long unshare_flags) } if (new_nsproxy) - put_nsproxy(new_nsproxy); + put_and_finalize_nsproxy(new_nsproxy); bad_unshare_cleanup_ipc: if (new_ipc) diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c index f5b9ee6f6bbb..7b05bce75cde 100644 --- a/kernel/nsproxy.c +++ b/kernel/nsproxy.c @@ -117,7 +117,7 @@ int copy_namespaces(int flags, struct task_struct *tsk) goto out_pid; out: - put_nsproxy(old_ns); + put_and_finalize_nsproxy(old_ns); return err; out_pid: @@ -135,6 +135,20 @@ out_ns: goto out; } +struct nsproxy *put_nsproxy(struct nsproxy *ns) +{ + if (ns) { + if (atomic_dec_and_test(&ns->count)) { + if (ns->mnt_ns) { + put_mnt_ns(ns->mnt_ns); + ns->mnt_ns = NULL; + } + return ns; + } + } + return NULL; +} + void free_nsproxy(struct nsproxy *ns) { if (ns->mnt_ns) |