From: Dan Carpenter <dan.carpenter@oracle.com>
To: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: [PATCH] lib/test_kmod: Fix an integer overflow test
Date: Mon, 22 Jan 2018 10:27:54 +0000 [thread overview]
Message-ID: <20180122102754.GD23912@mwanda> (raw)
The main problem is that the parentheses are in the wrong place and the
unlikely() call returns either 0 or 1 so it's never less than zero. The
other problem is that signed integer overflows like "INT_MAX + 1" are
undefined behavior.
Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
diff --git a/lib/test_kmod.c b/lib/test_kmod.c
index e372b97eee13..30fd6d9e5361 100644
--- a/lib/test_kmod.c
+++ b/lib/test_kmod.c
@@ -1141,7 +1141,7 @@ static struct kmod_test_device *register_test_dev_kmod(void)
mutex_lock(®_dev_mutex);
/* int should suffice for number of devices, test for wrap */
- if (unlikely(num_test_devs + 1) < 0) {
+ if (num_test_devs = INT_MAX) {
pr_err("reached limit of number of test devices\n");
goto out;
}
next reply other threads:[~2018-01-22 10:27 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-22 10:27 Dan Carpenter [this message]
2018-02-24 2:59 ` [PATCH] lib/test_kmod: Fix an integer overflow test Luis R. Rodriguez
2018-02-24 8:45 ` Dan Carpenter
2018-02-24 22:06 ` Luis R. Rodriguez
2018-02-24 23:34 ` Dan Carpenter
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