signal: Clear si_sys_private before copying siginfo to userspace

In preparation for unconditionally copying the whole of siginfo
to userspace clear si_sys_private.  So this kernel internal
value is guaranteed not to make it to userspace.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This commit is contained in:
Eric W. Biederman 2017-07-24 14:53:03 -05:00
parent aba1be2f8c
commit 9943d3accb

View File

@ -643,6 +643,9 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
spin_unlock(&tsk->sighand->siglock);
posixtimer_rearm(info);
spin_lock(&tsk->sighand->siglock);
/* Don't expose the si_sys_private value to userspace */
info->si_sys_private = 0;
}
#endif
return signr;