blob: d054de7db54f496bb501177dd895e57c57ddf179 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
|
From 17ae6ccfe5dd85605dc44534348b506f95d16a61 Mon Sep 17 00:00:00 2001
From: Li Jinyue <lijinyue@huawei.com>
Date: Thu, 14 Dec 2017 17:04:54 +0800
Subject: [PATCH] futex: Prevent overflow by strengthen input validation
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.
CVE: CVE-2018-6927
Upstream-Status: Backport [https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-4.14.y&id=17ae6ccfe5dd85605dc44534348b506f95d16a61]
Signed-off-by: Li Jinyue <lijinyue@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: peterz@infradead.org
Cc: dvhart@infradead.org
Link: https://lkml.kernel.org/r/1513242294-31786-1-git-send-email-lijinyue@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andreas Wellving <andreas.wellving@enea.com>
---
kernel/futex.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/kernel/futex.c b/kernel/futex.c
index 29ac5b64e7c7..52b3f4703158 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1878,6 +1878,9 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
struct futex_q *this, *next;
DEFINE_WAKE_Q(wake_q);
+ if (nr_wake < 0 || nr_requeue < 0)
+ return -EINVAL;
+
/*
* When PI not supported: return -ENOSYS if requeue_pi is true,
* consequently the compiler knows requeue_pi is always false past
--
2.20.1
|
