Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Sender: "elver via sendgmr" <elver@elver.muc.corp.google.com>
Date:   Thu, 22 Oct 2020 13:45:52 +0200
Message-Id: <20201022114553.2440135-1-elver@google.com>
Mime-Version: 1.0
Subject: [PATCH v2 1/2] kcsan: selftest: Ensure that address is at least PAGE_SIZE
From:   Marco Elver <elver@google.com>
To:     elver@google.com, paulmck@kernel.org
Cc:     mark.rutland@arm.com, dvyukov@google.com,
        kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

In preparation of supporting only addresses not within the NULL page,
change the selftest to never use addresses that are less than PAGE_SIZE.

Signed-off-by: Marco Elver <elver@google.com>
---
v2:
* Introduce patch to series.
---
 kernel/kcsan/selftest.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/kcsan/selftest.c b/kernel/kcsan/selftest.c
index d98bc208d06d..9014a3a82cf9 100644
--- a/kernel/kcsan/selftest.c
+++ b/kernel/kcsan/selftest.c
@@ -33,6 +33,9 @@ static bool test_encode_decode(void)
 		unsigned long addr;
 
 		prandom_bytes(&addr, sizeof(addr));
+		if (addr < PAGE_SIZE)
+			addr = PAGE_SIZE;
+
 		if (WARN_ON(!check_encodable(addr, size)))
 			return false;
 
-- 
2.29.0.rc1.297.gfa9743e501-goog