aio: add timeout validity check for io_[p]getevents

maillist inclusion
category: bugfix
bugzilla: 47445
CVE: NA

Reference: https://lore.kernel.org/lkml/1564451504-27906-1-git-send-email-yi.zhang@huawei.com/

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

io_[p]getevents syscall should return -EINVAL if timeout is out of
range, add this validity check.
Signed-off-by: Nzhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: NJeff Moyer <jmoyer@redhat.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Nyangerkun <yangerkun@huawei.com>
Reviewed-by: Nzhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

fs/aio.c

@@ -2050,10 +2050,17 @@ static long do_io_getevents(aio_context_t ctx_id,
 		struct io_event __user *events,
 		struct timespec64 *ts)
 {
-	ktime_t until = ts ? timespec64_to_ktime(*ts) : KTIME_MAX;
-	struct kioctx *ioctx = lookup_ioctx(ctx_id);
+	ktime_t until = KTIME_MAX;
+	struct kioctx *ioctx = NULL;
 	long ret = -EINVAL;
 
+	if (ts) {
+		if (!timespec64_valid(ts))
+			return ret;
+		until = timespec64_to_ktime(*ts);
+	}
+
+	ioctx = lookup_ioctx(ctx_id);
 	if (likely(ioctx)) {
 		if (likely(min_nr <= nr && min_nr >= 0))
 			ret = read_events(ioctx, min_nr, nr, events, until);