The patch titled
Subject: lib/test_kasan: add bitops tests
has been added to the -mm tree. Its filename is
lib-test_kasan-add-bitops-tests.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/lib-test_kasan-add-bitops-tests.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/lib-test_kasan-add-bitops-tests.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Marco Elver <elver@xxxxxxxxxx>
Subject: lib/test_kasan: add bitops tests
Patch series "Bitops instrumentation for KASAN", v5.
This patch (of 3):
This adds bitops tests to the test_kasan module. In a follow-up patch,
support for bitops instrumentation will be added.
Link: http://lkml.kernel.org/r/20190613125950.197667-2-elver@xxxxxxxxxx
Signed-off-by: Marco Elver <elver@xxxxxxxxxx>
Acked-by: Mark Rutland <mark.rutland@xxxxxxx>
Reviewed-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Cc: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/test_kasan.c | 81 +++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 78 insertions(+), 3 deletions(-)
--- a/lib/test_kasan.c~lib-test_kasan-add-bitops-tests
+++ a/lib/test_kasan.c
@@ -11,16 +11,17 @@
#define pr_fmt(fmt) "kasan test: %s " fmt, __func__
+#include <linux/bitops.h>
#include <linux/delay.h>
+#include <linux/kasan.h>
#include <linux/kernel.h>
-#include <linux/mman.h>
#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/module.h>
#include <linux/printk.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/uaccess.h>
-#include <linux/module.h>
-#include <linux/kasan.h>
/*
* Note: test functions are marked noinline so that their names appear in
@@ -623,6 +624,79 @@ static noinline void __init kasan_string
strnlen(ptr, 1);
}
+static noinline void __init kasan_bitops(void)
+{
+ /*
+ * Allocate 1 more byte, which causes kzalloc to round up to 16-bytes;
+ * this way we do not actually corrupt other memory.
+ */
+ long *bits = kzalloc(sizeof(*bits) + 1, GFP_KERNEL);
+ if (!bits)
+ return;
+
+ /*
+ * Below calls try to access bit within allocated memory; however, the
+ * below accesses are still out-of-bounds, since bitops are defined to
+ * operate on the whole long the bit is in.
+ */
+ pr_info("out-of-bounds in set_bit\n");
+ set_bit(BITS_PER_LONG, bits);
+
+ pr_info("out-of-bounds in __set_bit\n");
+ __set_bit(BITS_PER_LONG, bits);
+
+ pr_info("out-of-bounds in clear_bit\n");
+ clear_bit(BITS_PER_LONG, bits);
+
+ pr_info("out-of-bounds in __clear_bit\n");
+ __clear_bit(BITS_PER_LONG, bits);
+
+ pr_info("out-of-bounds in clear_bit_unlock\n");
+ clear_bit_unlock(BITS_PER_LONG, bits);
+
+ pr_info("out-of-bounds in __clear_bit_unlock\n");
+ __clear_bit_unlock(BITS_PER_LONG, bits);
+
+ pr_info("out-of-bounds in change_bit\n");
+ change_bit(BITS_PER_LONG, bits);
+
+ pr_info("out-of-bounds in __change_bit\n");
+ __change_bit(BITS_PER_LONG, bits);
+
+ /*
+ * Below calls try to access bit beyond allocated memory.
+ */
+ pr_info("out-of-bounds in test_and_set_bit\n");
+ test_and_set_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
+
+ pr_info("out-of-bounds in __test_and_set_bit\n");
+ __test_and_set_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
+
+ pr_info("out-of-bounds in test_and_set_bit_lock\n");
+ test_and_set_bit_lock(BITS_PER_LONG + BITS_PER_BYTE, bits);
+
+ pr_info("out-of-bounds in test_and_clear_bit\n");
+ test_and_clear_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
+
+ pr_info("out-of-bounds in __test_and_clear_bit\n");
+ __test_and_clear_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
+
+ pr_info("out-of-bounds in test_and_change_bit\n");
+ test_and_change_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
+
+ pr_info("out-of-bounds in __test_and_change_bit\n");
+ __test_and_change_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
+
+ pr_info("out-of-bounds in test_bit\n");
+ (void)test_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
+
+#if defined(clear_bit_unlock_is_negative_byte)
+ pr_info("out-of-bounds in clear_bit_unlock_is_negative_byte\n");
+ clear_bit_unlock_is_negative_byte(BITS_PER_LONG + BITS_PER_BYTE, bits);
+#endif
+ kfree(bits);
+}
+
static int __init kmalloc_tests_init(void)
{
/*
@@ -664,6 +738,7 @@ static int __init kmalloc_tests_init(voi
kasan_memchr();
kasan_memcmp();
kasan_strings();
+ kasan_bitops();
kasan_restore_multi_shot(multishot);
_
Patches currently in -mm which might be from elver@xxxxxxxxxx are
lib-test_kasan-add-bitops-tests.patch
x86-use-static_cpu_has-in-uaccess-region-to-avoid-instrumentation.patch
asm-generic-x86-add-bitops-instrumentation-for-kasan.patch
mm-kasan-print-frame-description-for-stack-bugs.patch
