ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/drivers/misc/lkdtm/heap.c b/marvell/linux/drivers/misc/lkdtm/heap.c
new file mode 100644
index 0000000..1323bc1
--- /dev/null
+++ b/marvell/linux/drivers/misc/lkdtm/heap.c
@@ -0,0 +1,221 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This is for all the tests relating directly to heap memory, including
+ * page allocation and slab allocations.
+ */
+#include "lkdtm.h"
+#include <linux/slab.h>
+#include <linux/sched.h>
+
+static struct kmem_cache *double_free_cache;
+static struct kmem_cache *a_cache;
+static struct kmem_cache *b_cache;
+
+/*
+ * This tries to stay within the next largest power-of-2 kmalloc cache
+ * to avoid actually overwriting anything important if it's not detected
+ * correctly.
+ */
+void lkdtm_OVERWRITE_ALLOCATION(void)
+{
+ size_t len = 1020;
+ u32 *data = kmalloc(len, GFP_KERNEL);
+ if (!data)
+ return;
+
+ data[1024 / sizeof(u32)] = 0x12345678;
+ kfree(data);
+}
+
+void lkdtm_WRITE_AFTER_FREE(void)
+{
+ int *base, *again;
+ size_t len = 1024;
+ /*
+ * The slub allocator uses the first word to store the free
+ * pointer in some configurations. Use the middle of the
+ * allocation to avoid running into the freelist
+ */
+ size_t offset = (len / sizeof(*base)) / 2;
+
+ base = kmalloc(len, GFP_KERNEL);
+ if (!base)
+ return;
+ pr_info("Allocated memory %p-%p\n", base, &base[offset * 2]);
+ pr_info("Attempting bad write to freed memory at %p\n",
+ &base[offset]);
+ kfree(base);
+ base[offset] = 0x0abcdef0;
+ /* Attempt to notice the overwrite. */
+ again = kmalloc(len, GFP_KERNEL);
+ kfree(again);
+ if (again != base)
+ pr_info("Hmm, didn't get the same memory range.\n");
+}
+
+void lkdtm_READ_AFTER_FREE(void)
+{
+ int *base, *val, saw;
+ size_t len = 1024;
+ /*
+ * The slub allocator will use the either the first word or
+ * the middle of the allocation to store the free pointer,
+ * depending on configurations. Store in the second word to
+ * avoid running into the freelist.
+ */
+ size_t offset = sizeof(*base);
+
+ base = kmalloc(len, GFP_KERNEL);
+ if (!base) {
+ pr_info("Unable to allocate base memory.\n");
+ return;
+ }
+
+ val = kmalloc(len, GFP_KERNEL);
+ if (!val) {
+ pr_info("Unable to allocate val memory.\n");
+ kfree(base);
+ return;
+ }
+
+ *val = 0x12345678;
+ base[offset] = *val;
+ pr_info("Value in memory before free: %x\n", base[offset]);
+
+ kfree(base);
+
+ pr_info("Attempting bad read from freed memory\n");
+ saw = base[offset];
+ if (saw != *val) {
+ /* Good! Poisoning happened, so declare a win. */
+ pr_info("Memory correctly poisoned (%x)\n", saw);
+ BUG();
+ }
+ pr_info("Memory was not poisoned\n");
+
+ kfree(val);
+}
+
+void lkdtm_WRITE_BUDDY_AFTER_FREE(void)
+{
+ unsigned long p = __get_free_page(GFP_KERNEL);
+ if (!p) {
+ pr_info("Unable to allocate free page\n");
+ return;
+ }
+
+ pr_info("Writing to the buddy page before free\n");
+ memset((void *)p, 0x3, PAGE_SIZE);
+ free_page(p);
+ schedule();
+ pr_info("Attempting bad write to the buddy page after free\n");
+ memset((void *)p, 0x78, PAGE_SIZE);
+ /* Attempt to notice the overwrite. */
+ p = __get_free_page(GFP_KERNEL);
+ free_page(p);
+ schedule();
+}
+
+void lkdtm_READ_BUDDY_AFTER_FREE(void)
+{
+ unsigned long p = __get_free_page(GFP_KERNEL);
+ int saw, *val;
+ int *base;
+
+ if (!p) {
+ pr_info("Unable to allocate free page\n");
+ return;
+ }
+
+ val = kmalloc(1024, GFP_KERNEL);
+ if (!val) {
+ pr_info("Unable to allocate val memory.\n");
+ free_page(p);
+ return;
+ }
+
+ base = (int *)p;
+
+ *val = 0x12345678;
+ base[0] = *val;
+ pr_info("Value in memory before free: %x\n", base[0]);
+ free_page(p);
+ pr_info("Attempting to read from freed memory\n");
+ saw = base[0];
+ if (saw != *val) {
+ /* Good! Poisoning happened, so declare a win. */
+ pr_info("Memory correctly poisoned (%x)\n", saw);
+ BUG();
+ }
+ pr_info("Buddy page was not poisoned\n");
+
+ kfree(val);
+}
+
+void lkdtm_SLAB_FREE_DOUBLE(void)
+{
+ int *val;
+
+ val = kmem_cache_alloc(double_free_cache, GFP_KERNEL);
+ if (!val) {
+ pr_info("Unable to allocate double_free_cache memory.\n");
+ return;
+ }
+
+ /* Just make sure we got real memory. */
+ *val = 0x12345678;
+ pr_info("Attempting double slab free ...\n");
+ kmem_cache_free(double_free_cache, val);
+ kmem_cache_free(double_free_cache, val);
+}
+
+void lkdtm_SLAB_FREE_CROSS(void)
+{
+ int *val;
+
+ val = kmem_cache_alloc(a_cache, GFP_KERNEL);
+ if (!val) {
+ pr_info("Unable to allocate a_cache memory.\n");
+ return;
+ }
+
+ /* Just make sure we got real memory. */
+ *val = 0x12345679;
+ pr_info("Attempting cross-cache slab free ...\n");
+ kmem_cache_free(b_cache, val);
+}
+
+void lkdtm_SLAB_FREE_PAGE(void)
+{
+ unsigned long p = __get_free_page(GFP_KERNEL);
+
+ pr_info("Attempting non-Slab slab free ...\n");
+ kmem_cache_free(NULL, (void *)p);
+ free_page(p);
+}
+
+/*
+ * We have constructors to keep the caches distinctly separated without
+ * needing to boot with "slab_nomerge".
+ */
+static void ctor_double_free(void *region)
+{ }
+static void ctor_a(void *region)
+{ }
+static void ctor_b(void *region)
+{ }
+
+void __init lkdtm_heap_init(void)
+{
+ double_free_cache = kmem_cache_create("lkdtm-heap-double_free",
+ 64, 0, 0, ctor_double_free);
+ a_cache = kmem_cache_create("lkdtm-heap-a", 64, 0, 0, ctor_a);
+ b_cache = kmem_cache_create("lkdtm-heap-b", 64, 0, 0, ctor_b);
+}
+
+void __exit lkdtm_heap_exit(void)
+{
+ kmem_cache_destroy(double_free_cache);
+ kmem_cache_destroy(a_cache);
+ kmem_cache_destroy(b_cache);
+}