From b6fe2d117e98805ee76352e6468f87d494a97292 Mon Sep 17 00:00:00 2001 From: Vitaly Mayatskikh Date: Wed, 23 Sep 2009 15:56:52 -0700 Subject: wait_noreap_copyout(): check for ->wo_info != NULL Current behaviour of sys_waitid() looks odd. If user passes infop == NULL, sys_waitid() returns success. When user additionally specifies flag WNOWAIT, sys_waitid() returns -EFAULT on the same conditions. When user combines WNOWAIT with WCONTINUED, sys_waitid() again returns success. This patch adds check for ->wo_info in wait_noreap_copyout(). User-visible change: starting from this commit, sys_waitid() always checks infop != NULL and does not fail if it is NULL. Signed-off-by: Vitaly Mayatskikh Reviewed-by: Oleg Nesterov Cc: Roland McGrath Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/exit.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) (limited to 'kernel/exit.c') diff --git a/kernel/exit.c b/kernel/exit.c index 2cc69eb8db2a..6c75ff83a8fe 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -1140,18 +1140,20 @@ static int wait_noreap_copyout(struct wait_opts *wo, struct task_struct *p, put_task_struct(p); infop = wo->wo_info; - 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); + 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); + } if (!retval) retval = pid; return retval; -- cgit v1.2.3