[PATCH v3 1/7] kasan: Modify kmalloc_large_oob_right(), add kmalloc_pagealloc_oob_right()

[Alexander Potapenko]

Rename kmalloc_large_oob_right() to kmalloc_pagealloc_oob_right(), as the
test only checks the page allocator functionality.
Also reimplement kmalloc_large_oob_right() so that the test allocates a
large enough chunk of memory that still does not trigger the page
allocator fallback.

Signed-off-by: Alexander Potapenko 
---
v2: - Merged "kasan: Change the behavior of kmalloc_large_oob_right" and
  "kasan: Changed kmalloc_large_oob_right, added kmalloc_pagealloc_oob_right"
  from v1

v3: - Minor description changes
---
 lib/test_kasan.c | 28 +++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/lib/test_kasan.c b/lib/test_kasan.c
index c32f3b0..90ad74f 100644
--- a/lib/test_kasan.c
+++ b/lib/test_kasan.c
@@ -65,11 +65,34 @@ static noinline void __init kmalloc_node_oob_right(void)
kfree(ptr);
 }
 
-static noinline void __init kmalloc_large_oob_right(void)
+#ifdef CONFIG_SLUB
+static noinline void __init kmalloc_pagealloc_oob_right(void)
 {
char *ptr;
size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
 
+   /* Allocate a chunk that does not fit into a SLUB cache to trigger
+* the page allocator fallback.
+*/
+   pr_info("kmalloc pagealloc allocation: out-of-bounds to right\n");
+   ptr = kmalloc(size, GFP_KERNEL);
+   if (!ptr) {
+   pr_err("Allocation failed\n");
+   return;
+   }
+
+   ptr[size] = 0;
+   kfree(ptr);
+}
+#endif
+
+static noinline void __init kmalloc_large_oob_right(void)
+{
+   char *ptr;
+   size_t size = KMALLOC_MAX_CACHE_SIZE - 256;
+   /* Allocate a chunk that is large enough, but still fits into a slab
+* and does not trigger the page allocator fallback in SLUB.
+*/
pr_info("kmalloc large allocation: out-of-bounds to right\n");
ptr = kmalloc(size, GFP_KERNEL);
if (!ptr) {
@@ -324,6 +347,9 @@ static int __init kmalloc_tests_init(void)
kmalloc_oob_right();
kmalloc_oob_left();
kmalloc_node_oob_right();
+#ifdef CONFIG_SLUB
+   kmalloc_pagealloc_oob_right();
+#endif
kmalloc_large_oob_right();
kmalloc_oob_krealloc_more();
kmalloc_oob_krealloc_less();
-- 
2.7.0.rc3.207.g0ac5344

[PATCH v3 1/7] kasan: Modify kmalloc_large_oob_right(), add kmalloc_pagealloc_oob_right()

[Alexander Potapenko]

Rename kmalloc_large_oob_right() to kmalloc_pagealloc_oob_right(), as the
test only checks the page allocator functionality.
Also reimplement kmalloc_large_oob_right() so that the test allocates a
large enough chunk of memory that still does not trigger the page
allocator fallback.

Signed-off-by: Alexander Potapenko 
---
v2: - Merged "kasan: Change the behavior of kmalloc_large_oob_right" and
  "kasan: Changed kmalloc_large_oob_right, added kmalloc_pagealloc_oob_right"
  from v1

v3: - Minor description changes
---
 lib/test_kasan.c | 28 +++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/lib/test_kasan.c b/lib/test_kasan.c
index c32f3b0..90ad74f 100644
--- a/lib/test_kasan.c
+++ b/lib/test_kasan.c
@@ -65,11 +65,34 @@ static noinline void __init kmalloc_node_oob_right(void)
kfree(ptr);
 }
 
-static noinline void __init kmalloc_large_oob_right(void)
+#ifdef CONFIG_SLUB
+static noinline void __init kmalloc_pagealloc_oob_right(void)
 {
char *ptr;
size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
 
+   /* Allocate a chunk that does not fit into a SLUB cache to trigger
+* the page allocator fallback.
+*/
+   pr_info("kmalloc pagealloc allocation: out-of-bounds to right\n");
+   ptr = kmalloc(size, GFP_KERNEL);
+   if (!ptr) {
+   pr_err("Allocation failed\n");
+   return;
+   }
+
+   ptr[size] = 0;
+   kfree(ptr);
+}
+#endif
+
+static noinline void __init kmalloc_large_oob_right(void)
+{
+   char *ptr;
+   size_t size = KMALLOC_MAX_CACHE_SIZE - 256;
+   /* Allocate a chunk that is large enough, but still fits into a slab
+* and does not trigger the page allocator fallback in SLUB.
+*/
pr_info("kmalloc large allocation: out-of-bounds to right\n");
ptr = kmalloc(size, GFP_KERNEL);
if (!ptr) {
@@ -324,6 +347,9 @@ static int __init kmalloc_tests_init(void)
kmalloc_oob_right();
kmalloc_oob_left();
kmalloc_node_oob_right();
+#ifdef CONFIG_SLUB
+   kmalloc_pagealloc_oob_right();
+#endif
kmalloc_large_oob_right();
kmalloc_oob_krealloc_more();
kmalloc_oob_krealloc_less();
-- 
2.7.0.rc3.207.g0ac5344