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author | Richard Guy Briggs <rgb@redhat.com> | 2013-08-15 18:05:12 -0400 |
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committer | Eric Paris <eparis@redhat.com> | 2014-03-20 10:11:54 -0400 |
commit | ad36d28293936b03d6b7996e9d6aadfd73c0eb08 (patch) | |
tree | 695d01a5792f57356ed7c1b759ff781dabda5c22 /include/linux | |
parent | 4a3eb726d1543c4b616b9a0a4d4c53ddd276f5f4 (diff) | |
download | linux-stable-ad36d28293936b03d6b7996e9d6aadfd73c0eb08.tar.gz linux-stable-ad36d28293936b03d6b7996e9d6aadfd73c0eb08.tar.bz2 linux-stable-ad36d28293936b03d6b7996e9d6aadfd73c0eb08.zip |
pid: get pid_t ppid of task in init_pid_ns
Added the functions task_ppid_nr_ns() and task_ppid_nr() to abstract the lookup
of the PPID (real_parent's pid_t) of a process, including rcu locking, in the
arbitrary and init_pid_ns.
This provides an alternative to sys_getppid(), which is relative to the child
process' pid namespace.
(informed by ebiederman's 6c621b7e)
Cc: stable@vger.kernel.org
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Diffstat (limited to 'include/linux')
-rw-r--r-- | include/linux/sched.h | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index 53f97eb8dbc7..116e301fb13f 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1561,6 +1561,24 @@ static inline pid_t task_tgid_vnr(struct task_struct *tsk) } +static int pid_alive(const struct task_struct *p); +static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns) +{ + pid_t pid = 0; + + rcu_read_lock(); + if (pid_alive(tsk)) + pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns); + rcu_read_unlock(); + + return pid; +} + +static inline pid_t task_ppid_nr(const struct task_struct *tsk) +{ + return task_ppid_nr_ns(tsk, &init_pid_ns); +} + static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) { @@ -1600,7 +1618,7 @@ static inline pid_t task_pgrp_nr(struct task_struct *tsk) * * Return: 1 if the process is alive. 0 otherwise. */ -static inline int pid_alive(struct task_struct *p) +static inline int pid_alive(const struct task_struct *p) { return p->pids[PIDTYPE_PID].pid != NULL; } |