From 06513916930125cdb4d0662f8b675d719abe7f32 Mon Sep 17 00:00:00 2001
From: Daniel Axtens <dja@axtens.net>
Date: Sat, 30 Nov 2019 17:54:53 -0800
Subject: [PATCH] kasan: add test for vmalloc
Test kasan vmalloc support by adding a new test to the module.
Link: http://lkml.kernel.org/r/20191031093909.9228-3-dja@axtens.net
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
lib/test_kasan.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/lib/test_kasan.c b/lib/test_kasan.c
index 49cc4d570a40b..328d33beae365 100644
--- a/lib/test_kasan.c
+++ b/lib/test_kasan.c
@@ -19,6 +19,7 @@
#include <linux/string.h>
#include <linux/uaccess.h>
#include <linux/io.h>
+#include <linux/vmalloc.h>
#include <asm/page.h>
@@ -748,6 +749,30 @@ static noinline void __init kmalloc_double_kzfree(void)
kzfree(ptr);
}
+#ifdef CONFIG_KASAN_VMALLOC
+static noinline void __init vmalloc_oob(void)
+{
+ void *area;
+
+ pr_info("vmalloc out-of-bounds\n");
+
+ /*
+ * We have to be careful not to hit the guard page.
+ * The MMU will catch that and crash us.
+ */
+ area = vmalloc(3000);
+ if (!area) {
+ pr_err("Allocation failed\n");
+ return;
+ }
+
+ ((volatile char *)area)[3100];
+ vfree(area);
+}
+#else
+static void __init vmalloc_oob(void) {}
+#endif
+
static int __init kmalloc_tests_init(void)
{
/*
@@ -793,6 +818,7 @@ static int __init kmalloc_tests_init(void)
kasan_strings();
kasan_bitops();
kmalloc_double_kzfree();
+ vmalloc_oob();
kasan_restore_multi_shot(multishot);
--
2.30.2