[PATCH 4.14 41/44] alpha: fix osf_wait4() breakage

From: Greg Kroah-Hartman
Date: Mon Jul 23 2018 - 08:30:38 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

commit f88a333b44318643282b8acc92af90deda441f5e upstream.

kernel_wait4() expects a userland address for status - it's only
rusage that goes as a kernel one (and needs a copyout afterwards)

[ Also, fix the prototype of kernel_wait4() to have that __user
annotation - Linus ]

Fixes: 92ebce5ac55d ("osf_wait4: switch to kernel_wait4()")
Cc: stable@xxxxxxxxxx # v4.13+
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/alpha/kernel/osf_sys.c | 5 +----
include/linux/sched/task.h | 2 +-
2 files changed, 2 insertions(+), 5 deletions(-)

--- a/arch/alpha/kernel/osf_sys.c
+++ b/arch/alpha/kernel/osf_sys.c
@@ -1183,13 +1183,10 @@ SYSCALL_DEFINE2(osf_getrusage, int, who,
SYSCALL_DEFINE4(osf_wait4, pid_t, pid, int __user *, ustatus, int, options,
struct rusage32 __user *, ur)
{
- unsigned int status = 0;
struct rusage r;
- long err = kernel_wait4(pid, &status, options, &r);
+ long err = kernel_wait4(pid, ustatus, options, &r);
if (err <= 0)
return err;
- if (put_user(status, ustatus))
- return -EFAULT;
if (!ur)
return err;
if (put_tv32(&ur->ru_utime, &r.ru_utime))
--- a/include/linux/sched/task.h
+++ b/include/linux/sched/task.h
@@ -75,7 +75,7 @@ extern long _do_fork(unsigned long, unsi
extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
struct task_struct *fork_idle(int);
extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
-extern long kernel_wait4(pid_t, int *, int, struct rusage *);
+extern long kernel_wait4(pid_t, int __user *, int, struct rusage *);

extern void free_task(struct task_struct *tsk);