Similar to commit 6ada1fc0e1c4
("time: settimeofday: Validate the values of tv from user"),
an unvalidated user input is multiplied by a constant, which can result
in an undefined behaviour for large values. While this is validated
later, we should avoid triggering undefined behaviour.

Signed-off-by: zhengbin <zhengbi...@huawei.com>
---
 kernel/time/time.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/kernel/time/time.c b/kernel/time/time.c
index 7f7d691..5c54ca6 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -251,6 +251,10 @@ COMPAT_SYSCALL_DEFINE2(settimeofday, struct old_timeval32 
__user *, tv,
        if (tv) {
                if (compat_get_timeval(&user_tv, tv))
                        return -EFAULT;
+
+               if (!timeval_valid(&user_tv))
+                       return -EINVAL;
+
                new_ts.tv_sec = user_tv.tv_sec;
                new_ts.tv_nsec = user_tv.tv_usec * NSEC_PER_USEC;
        }
--
2.7.4

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