aboutsummaryrefslogtreecommitdiffstats
path: root/lib
diff options
context:
space:
mode:
authorMark Rutland <mark.rutland@arm.com>2019-09-23 15:34:16 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-09-24 15:54:08 -0700
commitb92a953cb7f727c42a15ac2ea59bf3cf9c39370d (patch)
tree570be1078303f1f080a194accd659fc9d94a52c7 /lib
parentae8f06b31a83e54777514308a63f669a1fed519e (diff)
downloadlinux-yocto-b92a953cb7f727c42a15ac2ea59bf3cf9c39370d.tar.gz
linux-yocto-b92a953cb7f727c42a15ac2ea59bf3cf9c39370d.tar.bz2
linux-yocto-b92a953cb7f727c42a15ac2ea59bf3cf9c39370d.zip
lib/test_kasan.c: add roundtrip tests
In several places we need to be able to operate on pointers which have gone via a roundtrip: virt -> {phys,page} -> virt With KASAN_SW_TAGS, we can't preserve the tag for SLUB objects, and the {phys,page} -> virt conversion will use KASAN_TAG_KERNEL. This patch adds tests to ensure that this works as expected, without false positives which have recently been spotted [1,2] in testing. [1] https://lore.kernel.org/linux-arm-kernel/20190819114420.2535-1-walter-zh.wu@mediatek.com/ [2] https://lore.kernel.org/linux-arm-kernel/20190819132347.GB9927@lakrids.cambridge.arm.com/ [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/20190821153927.28630-1-mark.rutland@arm.com Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib')
-rw-r--r--lib/test_kasan.c41
1 files changed, 41 insertions, 0 deletions
diff --git a/lib/test_kasan.c b/lib/test_kasan.c
index b63b367a94e8..49cc4d570a40 100644
--- a/lib/test_kasan.c
+++ b/lib/test_kasan.c
@@ -18,6 +18,9 @@
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/uaccess.h>
+#include <linux/io.h>
+
+#include <asm/page.h>
/*
* Note: test functions are marked noinline so that their names appear in
@@ -337,6 +340,42 @@ static noinline void __init kmalloc_uaf2(void)
kfree(ptr2);
}
+static noinline void __init kfree_via_page(void)
+{
+ char *ptr;
+ size_t size = 8;
+ struct page *page;
+ unsigned long offset;
+
+ pr_info("invalid-free false positive (via page)\n");
+ ptr = kmalloc(size, GFP_KERNEL);
+ if (!ptr) {
+ pr_err("Allocation failed\n");
+ return;
+ }
+
+ page = virt_to_page(ptr);
+ offset = offset_in_page(ptr);
+ kfree(page_address(page) + offset);
+}
+
+static noinline void __init kfree_via_phys(void)
+{
+ char *ptr;
+ size_t size = 8;
+ phys_addr_t phys;
+
+ pr_info("invalid-free false positive (via phys)\n");
+ ptr = kmalloc(size, GFP_KERNEL);
+ if (!ptr) {
+ pr_err("Allocation failed\n");
+ return;
+ }
+
+ phys = virt_to_phys(ptr);
+ kfree(phys_to_virt(phys));
+}
+
static noinline void __init kmem_cache_oob(void)
{
char *p;
@@ -737,6 +776,8 @@ static int __init kmalloc_tests_init(void)
kmalloc_uaf();
kmalloc_uaf_memset();
kmalloc_uaf2();
+ kfree_via_page();
+ kfree_via_phys();
kmem_cache_oob();
memcg_accounted_kmem_cache();
kasan_stack_oob();