| From | Ben Hutchings <> | Date | Wed, 28 Feb 2018 15:20:18 +0000 | Subject | [PATCH 3.16 204/254] futex: Prevent overflow by strengthen input validation |
| |
3.16.55-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Li Jinyue <lijinyue@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 <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 [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> --- kernel/futex.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/kernel/futex.c +++ b/kernel/futex.c @@ -1531,6 +1531,9 @@ static int futex_requeue(u32 __user *uad struct futex_hash_bucket *hb1, *hb2; struct futex_q *this, *next; + if (nr_wake < 0 || nr_requeue < 0) + return -EINVAL; + if (requeue_pi) { /* * Requeue PI only works on two distinct uaddrs. This
|