kernel/sys.c: fix prototype of prctl_get_tid_address()

tid_addr is not a "pointer to (pointer to int in userspace)"; it is in
fact a "pointer to (pointer to int in userspace) in userspace".  So
sparse rightfully complains about passing a kernel pointer to
put_user().

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Rasmus Villemoes 2020-10-24 03:04:26 +02:00 committed by Linus Torvalds
parent 23224e4500
commit 986b9eacb2

View File

@ -2238,12 +2238,12 @@ static int prctl_set_mm(int opt, unsigned long addr,
}
#ifdef CONFIG_CHECKPOINT_RESTORE
static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr)
static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr)
{
return put_user(me->clear_child_tid, tid_addr);
}
#else
static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr)
static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr)
{
return -EINVAL;
}
@ -2427,7 +2427,7 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
error = prctl_set_mm(arg2, arg3, arg4, arg5);
break;
case PR_GET_TID_ADDRESS:
error = prctl_get_tid_address(me, (int __user **)arg2);
error = prctl_get_tid_address(me, (int __user * __user *)arg2);
break;
case PR_SET_CHILD_SUBREAPER:
me->signal->is_child_subreaper = !!arg2;