diff options
| -rw-r--r-- | include/linux/pid.h | 4 | ||||
| -rw-r--r-- | include/uapi/linux/wait.h | 1 | ||||
| -rw-r--r-- | kernel/exit.c | 33 | ||||
| -rw-r--r-- | kernel/fork.c | 8 | ||||
| -rw-r--r-- | kernel/signal.c | 7 |
5 files changed, 48 insertions, 5 deletions
diff --git a/include/linux/pid.h b/include/linux/pid.h index 2a83e434db9d..9645b1194c98 100644 --- a/include/linux/pid.h +++ b/include/linux/pid.h @@ -72,6 +72,10 @@ extern struct pid init_struct_pid; extern const struct file_operations pidfd_fops; +struct file; + +extern struct pid *pidfd_pid(const struct file *file); + static inline struct pid *get_pid(struct pid *pid) { if (pid) diff --git a/include/uapi/linux/wait.h b/include/uapi/linux/wait.h index ac49a220cf2a..85b809fc9f11 100644 --- a/include/uapi/linux/wait.h +++ b/include/uapi/linux/wait.h @@ -17,6 +17,7 @@ #define P_ALL 0 #define P_PID 1 #define P_PGID 2 +#define P_PIDFD 3 #endif /* _UAPI_LINUX_WAIT_H */ diff --git a/kernel/exit.c b/kernel/exit.c index a75b6a7f458a..64bb6893a37d 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -1552,6 +1552,23 @@ end: return retval; } +static struct pid *pidfd_get_pid(unsigned int fd) +{ + struct fd f; + struct pid *pid; + + f = fdget(fd); + if (!f.file) + return ERR_PTR(-EBADF); + + pid = pidfd_pid(f.file); + if (!IS_ERR(pid)) + get_pid(pid); + + fdput(f); + return pid; +} + static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop, int options, struct rusage *ru) { @@ -1574,19 +1591,29 @@ static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop, type = PIDTYPE_PID; if (upid <= 0) return -EINVAL; + + pid = find_get_pid(upid); break; case P_PGID: type = PIDTYPE_PGID; if (upid <= 0) return -EINVAL; + + pid = find_get_pid(upid); + break; + case P_PIDFD: + type = PIDTYPE_PID; + if (upid < 0) + return -EINVAL; + + pid = pidfd_get_pid(upid); + if (IS_ERR(pid)) + return PTR_ERR(pid); break; default: return -EINVAL; } - if (type < PIDTYPE_MAX) - pid = find_get_pid(upid); - wo.wo_type = type; wo.wo_pid = pid; wo.wo_flags = options; diff --git a/kernel/fork.c b/kernel/fork.c index d8ae0f1b4148..b169e2ca2d84 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1690,6 +1690,14 @@ static inline void rcu_copy_process(struct task_struct *p) #endif /* #ifdef CONFIG_TASKS_RCU */ } +struct pid *pidfd_pid(const struct file *file) +{ + if (file->f_op == &pidfd_fops) + return file->private_data; + + return ERR_PTR(-EBADF); +} + static int pidfd_release(struct inode *inode, struct file *file) { struct pid *pid = file->private_data; diff --git a/kernel/signal.c b/kernel/signal.c index 91b789dd6e72..2e567f64812f 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -3672,8 +3672,11 @@ static int copy_siginfo_from_user_any(kernel_siginfo_t *kinfo, siginfo_t *info) static struct pid *pidfd_to_pid(const struct file *file) { - if (file->f_op == &pidfd_fops) - return file->private_data; + struct pid *pid; + + pid = pidfd_pid(file); + if (!IS_ERR(pid)) + return pid; return tgid_pidfd_to_pid(file); } |