4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Li Jinyue <lijin...@huawei.com> commit fbe0e839d1e22d88810f3ee3e2f1479be4c0aa4a upstream. UBSAN reports signed integer overflow in kernel/futex.c: UBSAN: Undefined behaviour in kernel/futex.c:2041:18 signed integer overflow: 0 - -2147483648 cannot be represented in type 'int' Add a sanity check to catch negative values of nr_wake and nr_requeue. Signed-off-by: Li Jinyue <lijin...@huawei.com> Signed-off-by: Thomas Gleixner <t...@linutronix.de> Cc: pet...@infradead.org Cc: dvh...@infradead.org Link: https://lkml.kernel.org/r/1513242294-31786-1-git-send-email-lijin...@huawei.com Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- kernel/futex.c | 3 +++ 1 file changed, 3 insertions(+) --- a/kernel/futex.c +++ b/kernel/futex.c @@ -1711,6 +1711,9 @@ static int futex_requeue(u32 __user *uad struct futex_q *this, *next; WAKE_Q(wake_q); + if (nr_wake < 0 || nr_requeue < 0) + return -EINVAL; + if (requeue_pi) { /* * Requeue PI only works on two distinct uaddrs. This
