From: Li Jinyue lijinyue@huawei.com
This patch has been added to the 4.1 stable tree. If you have any objections, please let us know.
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[ Upstream commit fbe0e839d1e22d88810f3ee3e2f1479be4c0aa4a ]
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.... Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- kernel/futex.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/kernel/futex.c b/kernel/futex.c index 959cc4fc6de5..4195616b27d9 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -1514,6 +1514,9 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags, 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