futex: Prevent overflow by strengthen input validation
authorLi Jinyue <lijinyue@huawei.com>
Thu, 14 Dec 2017 09:04:54 +0000 (17:04 +0800)
committerThomas Gleixner <tglx@linutronix.de>
Sun, 14 Jan 2018 17:55:03 +0000 (18:55 +0100)
commitfbe0e839d1e22d88810f3ee3e2f1479be4c0aa4a
tree43789fc1348223cbf15ac5ec425d830696c1f89b
parentc1e2f0eaf015fb7076d51a339011f2383e6dd389
futex: Prevent overflow by strengthen input validation

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 <lijinyue@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: peterz@infradead.org
Cc: dvhart@infradead.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1513242294-31786-1-git-send-email-lijinyue@huawei.com
kernel/futex.c