mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-11 21:38:32 +08:00
waitid(2): leave copyout of siginfo to syscall itself
have kernel_waitid() collect the information needed for siginfo into a small structure (waitid_info) passed to it; deal with copyout in sys_waitid()/compat_sys_waitid(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro
parent
359566faef
commit
67d7ddded3
168
kernel/exit.c
168
kernel/exit.c
@ -996,12 +996,19 @@ SYSCALL_DEFINE1(exit_group, int, error_code)
|
||||
return 0;
|
||||
}
|
||||
|
||||
struct waitid_info {
|
||||
pid_t pid;
|
||||
uid_t uid;
|
||||
int status;
|
||||
int cause;
|
||||
};
|
||||
|
||||
struct wait_opts {
|
||||
enum pid_type wo_type;
|
||||
int wo_flags;
|
||||
struct pid *wo_pid;
|
||||
|
||||
struct siginfo __user *wo_info;
|
||||
struct waitid_info *wo_info;
|
||||
int wo_stat;
|
||||
struct rusage *wo_rusage;
|
||||
|
||||
@ -1053,8 +1060,7 @@ eligible_child(struct wait_opts *wo, bool ptrace, struct task_struct *p)
|
||||
static int wait_noreap_copyout(struct wait_opts *wo, struct task_struct *p,
|
||||
pid_t pid, uid_t uid, int why, int status)
|
||||
{
|
||||
struct siginfo __user *infop;
|
||||
int retval = 0;
|
||||
struct waitid_info *infop;
|
||||
|
||||
if (wo->wo_rusage)
|
||||
getrusage(p, RUSAGE_BOTH, wo->wo_rusage);
|
||||
@ -1062,22 +1068,12 @@ static int wait_noreap_copyout(struct wait_opts *wo, struct task_struct *p,
|
||||
put_task_struct(p);
|
||||
infop = wo->wo_info;
|
||||
if (infop) {
|
||||
if (!retval)
|
||||
retval = put_user(SIGCHLD, &infop->si_signo);
|
||||
if (!retval)
|
||||
retval = put_user(0, &infop->si_errno);
|
||||
if (!retval)
|
||||
retval = put_user((short)why, &infop->si_code);
|
||||
if (!retval)
|
||||
retval = put_user(pid, &infop->si_pid);
|
||||
if (!retval)
|
||||
retval = put_user(uid, &infop->si_uid);
|
||||
if (!retval)
|
||||
retval = put_user(status, &infop->si_status);
|
||||
infop->cause = why;
|
||||
infop->pid = pid;
|
||||
infop->uid = uid;
|
||||
infop->status = status;
|
||||
}
|
||||
if (!retval)
|
||||
retval = pid;
|
||||
return retval;
|
||||
return pid;
|
||||
}
|
||||
|
||||
/*
|
||||
@ -1088,10 +1084,10 @@ static int wait_noreap_copyout(struct wait_opts *wo, struct task_struct *p,
|
||||
*/
|
||||
static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
|
||||
{
|
||||
int state, retval, status;
|
||||
int state, status;
|
||||
pid_t pid = task_pid_vnr(p);
|
||||
uid_t uid = from_kuid_munged(current_user_ns(), task_uid(p));
|
||||
struct siginfo __user *infop;
|
||||
struct waitid_info *infop;
|
||||
|
||||
if (!likely(wo->wo_flags & WEXITED))
|
||||
return 0;
|
||||
@ -1186,36 +1182,22 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
|
||||
|
||||
if (wo->wo_rusage)
|
||||
getrusage(p, RUSAGE_BOTH, wo->wo_rusage);
|
||||
retval = 0;
|
||||
status = (p->signal->flags & SIGNAL_GROUP_EXIT)
|
||||
? p->signal->group_exit_code : p->exit_code;
|
||||
wo->wo_stat = status;
|
||||
|
||||
infop = wo->wo_info;
|
||||
if (!retval && infop)
|
||||
retval = put_user(SIGCHLD, &infop->si_signo);
|
||||
if (!retval && infop)
|
||||
retval = put_user(0, &infop->si_errno);
|
||||
if (!retval && infop) {
|
||||
int why;
|
||||
|
||||
if (infop) {
|
||||
if ((status & 0x7f) == 0) {
|
||||
why = CLD_EXITED;
|
||||
status >>= 8;
|
||||
infop->cause = CLD_EXITED;
|
||||
infop->status = status >> 8;
|
||||
} else {
|
||||
why = (status & 0x80) ? CLD_DUMPED : CLD_KILLED;
|
||||
status &= 0x7f;
|
||||
infop->cause = (status & 0x80) ? CLD_DUMPED : CLD_KILLED;
|
||||
infop->status = status & 0x7f;
|
||||
}
|
||||
retval = put_user((short)why, &infop->si_code);
|
||||
if (!retval)
|
||||
retval = put_user(status, &infop->si_status);
|
||||
infop->pid = pid;
|
||||
infop->uid = uid;
|
||||
}
|
||||
if (!retval && infop)
|
||||
retval = put_user(pid, &infop->si_pid);
|
||||
if (!retval && infop)
|
||||
retval = put_user(uid, &infop->si_uid);
|
||||
if (!retval)
|
||||
retval = pid;
|
||||
|
||||
if (state == EXIT_TRACE) {
|
||||
write_lock_irq(&tasklist_lock);
|
||||
@ -1232,7 +1214,7 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
|
||||
if (state == EXIT_DEAD)
|
||||
release_task(p);
|
||||
|
||||
return retval;
|
||||
return pid;
|
||||
}
|
||||
|
||||
static int *task_stopped_code(struct task_struct *p, bool ptrace)
|
||||
@ -1268,8 +1250,8 @@ static int *task_stopped_code(struct task_struct *p, bool ptrace)
|
||||
static int wait_task_stopped(struct wait_opts *wo,
|
||||
int ptrace, struct task_struct *p)
|
||||
{
|
||||
struct siginfo __user *infop;
|
||||
int retval, exit_code, *p_code, why;
|
||||
struct waitid_info *infop;
|
||||
int exit_code, *p_code, why;
|
||||
uid_t uid = 0; /* unneeded, required by compiler */
|
||||
pid_t pid;
|
||||
|
||||
@ -1320,28 +1302,19 @@ unlock_sig:
|
||||
|
||||
if (wo->wo_rusage)
|
||||
getrusage(p, RUSAGE_BOTH, wo->wo_rusage);
|
||||
retval = 0;
|
||||
wo->wo_stat = (exit_code << 8) | 0x7f;
|
||||
|
||||
infop = wo->wo_info;
|
||||
if (!retval && infop)
|
||||
retval = put_user(SIGCHLD, &infop->si_signo);
|
||||
if (!retval && infop)
|
||||
retval = put_user(0, &infop->si_errno);
|
||||
if (!retval && infop)
|
||||
retval = put_user((short)why, &infop->si_code);
|
||||
if (!retval && infop)
|
||||
retval = put_user(exit_code, &infop->si_status);
|
||||
if (!retval && infop)
|
||||
retval = put_user(pid, &infop->si_pid);
|
||||
if (!retval && infop)
|
||||
retval = put_user(uid, &infop->si_uid);
|
||||
if (!retval)
|
||||
retval = pid;
|
||||
if (infop) {
|
||||
infop->cause = why;
|
||||
infop->status = exit_code;
|
||||
infop->pid = pid;
|
||||
infop->uid = uid;
|
||||
}
|
||||
put_task_struct(p);
|
||||
|
||||
BUG_ON(!retval);
|
||||
return retval;
|
||||
BUG_ON(!pid);
|
||||
return pid;
|
||||
}
|
||||
|
||||
/*
|
||||
@ -1618,7 +1591,7 @@ end:
|
||||
return retval;
|
||||
}
|
||||
|
||||
static long kernel_waitid(int which, pid_t upid, struct siginfo __user *infop,
|
||||
static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop,
|
||||
int options, struct rusage *ru)
|
||||
{
|
||||
struct wait_opts wo;
|
||||
@ -1660,27 +1633,8 @@ static long kernel_waitid(int which, pid_t upid, struct siginfo __user *infop,
|
||||
wo.wo_rusage = ru;
|
||||
ret = do_wait(&wo);
|
||||
|
||||
if (ret > 0) {
|
||||
if (ret > 0)
|
||||
ret = 0;
|
||||
} else if (infop) {
|
||||
/*
|
||||
* For a WNOHANG return, clear out all the fields
|
||||
* we would set so the user can easily tell the
|
||||
* difference.
|
||||
*/
|
||||
if (!ret)
|
||||
ret = put_user(0, &infop->si_signo);
|
||||
if (!ret)
|
||||
ret = put_user(0, &infop->si_errno);
|
||||
if (!ret)
|
||||
ret = put_user(0, &infop->si_code);
|
||||
if (!ret)
|
||||
ret = put_user(0, &infop->si_pid);
|
||||
if (!ret)
|
||||
ret = put_user(0, &infop->si_uid);
|
||||
if (!ret)
|
||||
ret = put_user(0, &infop->si_status);
|
||||
}
|
||||
|
||||
put_pid(pid);
|
||||
return ret;
|
||||
@ -1690,12 +1644,24 @@ SYSCALL_DEFINE5(waitid, int, which, pid_t, upid, struct siginfo __user *,
|
||||
infop, int, options, struct rusage __user *, ru)
|
||||
{
|
||||
struct rusage r;
|
||||
long err = kernel_waitid(which, upid, infop, options, ru ? &r : NULL);
|
||||
struct waitid_info info = {.status = 0};
|
||||
long err = kernel_waitid(which, upid, &info, options, ru ? &r : NULL);
|
||||
|
||||
if (!err) {
|
||||
if (ru && copy_to_user(ru, &r, sizeof(struct rusage)))
|
||||
return -EFAULT;
|
||||
}
|
||||
if (!infop)
|
||||
return err;
|
||||
|
||||
if (put_user(err ? 0 : SIGCHLD, &infop->si_signo) ||
|
||||
put_user(0, &infop->si_errno) ||
|
||||
put_user((short)info.cause, &infop->si_code) ||
|
||||
put_user(info.pid, &infop->si_pid) ||
|
||||
put_user(info.uid, &infop->si_uid) ||
|
||||
put_user(info.status, &infop->si_status))
|
||||
err = -EFAULT;
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
@ -1785,33 +1751,27 @@ COMPAT_SYSCALL_DEFINE5(waitid,
|
||||
struct compat_siginfo __user *, infop, int, options,
|
||||
struct compat_rusage __user *, uru)
|
||||
{
|
||||
siginfo_t info;
|
||||
struct rusage ru;
|
||||
long ret;
|
||||
mm_segment_t old_fs = get_fs();
|
||||
struct waitid_info info = {.status = 0};
|
||||
long err = kernel_waitid(which, pid, &info, options, uru ? &ru : NULL);
|
||||
|
||||
memset(&info, 0, sizeof(info));
|
||||
|
||||
set_fs(KERNEL_DS);
|
||||
ret = kernel_waitid(which, pid, (siginfo_t __user *)&info, options,
|
||||
uru ? &ru : NULL);
|
||||
set_fs(old_fs);
|
||||
|
||||
if ((ret < 0) || (info.si_signo == 0))
|
||||
return ret;
|
||||
|
||||
if (uru) {
|
||||
/* sys_waitid() overwrites everything in ru */
|
||||
if (!err && uru) {
|
||||
/* kernel_waitid() overwrites everything in ru */
|
||||
if (COMPAT_USE_64BIT_TIME)
|
||||
ret = copy_to_user(uru, &ru, sizeof(ru));
|
||||
err = copy_to_user(uru, &ru, sizeof(ru));
|
||||
else
|
||||
ret = put_compat_rusage(&ru, uru);
|
||||
if (ret)
|
||||
err = put_compat_rusage(&ru, uru);
|
||||
if (err)
|
||||
return -EFAULT;
|
||||
}
|
||||
|
||||
BUG_ON(info.si_code & __SI_MASK);
|
||||
info.si_code |= __SI_CHLD;
|
||||
return copy_siginfo_to_user32(infop, &info);
|
||||
if (put_user(err ? 0 : SIGCHLD, &infop->si_signo) ||
|
||||
put_user(0, &infop->si_errno) ||
|
||||
put_user((short)info.cause, &infop->si_code) ||
|
||||
put_user(info.pid, &infop->si_pid) ||
|
||||
put_user(info.uid, &infop->si_uid) ||
|
||||
put_user(info.status, &infop->si_status))
|
||||
err = -EFAULT;
|
||||
return err;
|
||||
}
|
||||
#endif
|
||||
|
||||
Loading…
Reference in New Issue
Block a user