task_xstate_cachep =
kmem_cache_create("task_xstate", xstate_size,
__alignof__(union thread_xstate),
- SLAB_PANIC, NULL);
+ SLAB_PANIC | SLAB_NOTRACK, NULL);
}
/*
#define __GFP_THISNODE ((__force gfp_t)0x40000u)/* No fallback, no policies */
#define __GFP_RECLAIMABLE ((__force gfp_t)0x80000u) /* Page is reclaimable */
#define __GFP_MOVABLE ((__force gfp_t)0x100000u) /* Page is movable */
+#define __GFP_NOTRACK ((__force gfp_t)0x200000u) /* Don't track with kmemcheck */
-#define __GFP_BITS_SHIFT 21 /* Room for 21 __GFP_FOO bits */
+/*
+ * This may seem redundant, but it's a way of annotating false positives vs.
+ * allocations that simply cannot be supported (e.g. page tables).
+ */
+#define __GFP_NOTRACK_FALSE_POSITIVE (__GFP_NOTRACK)
+
+#define __GFP_BITS_SHIFT 22 /* Room for 22 __GFP_FOO bits */
#define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
/* This equals 0, but use constants in case they ever change */
#ifdef CONFIG_KMEMCHECK
extern int kmemcheck_enabled;
+/* The slab-related functions. */
+void kmemcheck_alloc_shadow(struct kmem_cache *s, gfp_t flags, int node,
+ struct page *page, int order);
+void kmemcheck_free_shadow(struct kmem_cache *s, struct page *page, int order);
+void kmemcheck_slab_alloc(struct kmem_cache *s, gfp_t gfpflags, void *object,
+ size_t size);
+void kmemcheck_slab_free(struct kmem_cache *s, void *object, size_t size);
+
+void kmemcheck_show_pages(struct page *p, unsigned int n);
+void kmemcheck_hide_pages(struct page *p, unsigned int n);
+
+bool kmemcheck_page_is_tracked(struct page *p);
+
+void kmemcheck_mark_unallocated(void *address, unsigned int n);
+void kmemcheck_mark_uninitialized(void *address, unsigned int n);
+void kmemcheck_mark_initialized(void *address, unsigned int n);
+void kmemcheck_mark_freed(void *address, unsigned int n);
+
+void kmemcheck_mark_unallocated_pages(struct page *p, unsigned int n);
+void kmemcheck_mark_uninitialized_pages(struct page *p, unsigned int n);
+
int kmemcheck_show_addr(unsigned long address);
int kmemcheck_hide_addr(unsigned long address);
#else
#define kmemcheck_enabled 0
+static inline void
+kmemcheck_alloc_shadow(struct kmem_cache *s, gfp_t flags, int node,
+ struct page *page, int order)
+{
+}
+
+static inline void
+kmemcheck_free_shadow(struct kmem_cache *s, struct page *page, int order)
+{
+}
+
+static inline void
+kmemcheck_slab_alloc(struct kmem_cache *s, gfp_t gfpflags, void *object,
+ size_t size)
+{
+}
+
+static inline void kmemcheck_slab_free(struct kmem_cache *s, void *object,
+ size_t size)
+{
+}
+
+static inline bool kmemcheck_page_is_tracked(struct page *p)
+{
+ return false;
+}
#endif /* CONFIG_KMEMCHECK */
#endif /* LINUX_KMEMCHECK_H */
#define SLAB_NOLEAKTRACE 0x00800000UL /* Avoid kmemleak tracing */
+/* Don't track use of uninitialized memory */
+#ifdef CONFIG_KMEMCHECK
+# define SLAB_NOTRACK 0x01000000UL
+#else
+# define SLAB_NOTRACK 0x00000000UL
+#endif
+
/* The following flags affect the page allocator grouping pages by mobility */
#define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */
#define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */
/* create a slab on which task_structs can be allocated */
task_struct_cachep =
kmem_cache_create("task_struct", sizeof(struct task_struct),
- ARCH_MIN_TASKALIGN, SLAB_PANIC, NULL);
+ ARCH_MIN_TASKALIGN, SLAB_PANIC | SLAB_NOTRACK, NULL);
#endif
/* do the arch specific task caches init */
{
sighand_cachep = kmem_cache_create("sighand_cache",
sizeof(struct sighand_struct), 0,
- SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_DESTROY_BY_RCU,
- sighand_ctor);
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_DESTROY_BY_RCU|
+ SLAB_NOTRACK, sighand_ctor);
signal_cachep = kmem_cache_create("signal_cache",
sizeof(struct signal_struct), 0,
- SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_NOTRACK, NULL);
files_cachep = kmem_cache_create("files_cache",
sizeof(struct files_struct), 0,
- SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_NOTRACK, NULL);
fs_cachep = kmem_cache_create("fs_cache",
sizeof(struct fs_struct), 0,
- SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_NOTRACK, NULL);
mm_cachep = kmem_cache_create("mm_struct",
sizeof(struct mm_struct), ARCH_MIN_MMSTRUCT_ALIGN,
- SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_NOTRACK, NULL);
vm_area_cachep = KMEM_CACHE(vm_area_struct, SLAB_PANIC);
mmap_init();
}
obj-$(CONFIG_PAGE_POISONING) += debug-pagealloc.o
obj-$(CONFIG_SLAB) += slab.o
obj-$(CONFIG_SLUB) += slub.o
+obj-$(CONFIG_KMEMCHECK) += kmemcheck.o
obj-$(CONFIG_FAILSLAB) += failslab.o
obj-$(CONFIG_MEMORY_HOTPLUG) += memory_hotplug.o
obj-$(CONFIG_FS_XIP) += filemap_xip.o
--- /dev/null
+#include <linux/mm_types.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/kmemcheck.h>
+
+void kmemcheck_alloc_shadow(struct kmem_cache *s, gfp_t flags, int node,
+ struct page *page, int order)
+{
+ struct page *shadow;
+ int pages;
+ int i;
+
+ pages = 1 << order;
+
+ /*
+ * With kmemcheck enabled, we need to allocate a memory area for the
+ * shadow bits as well.
+ */
+ shadow = alloc_pages_node(node, flags, order);
+ if (!shadow) {
+ if (printk_ratelimit())
+ printk(KERN_ERR "kmemcheck: failed to allocate "
+ "shadow bitmap\n");
+ return;
+ }
+
+ for(i = 0; i < pages; ++i)
+ page[i].shadow = page_address(&shadow[i]);
+
+ /*
+ * Mark it as non-present for the MMU so that our accesses to
+ * this memory will trigger a page fault and let us analyze
+ * the memory accesses.
+ */
+ kmemcheck_hide_pages(page, pages);
+
+ /*
+ * Objects from caches that have a constructor don't get
+ * cleared when they're allocated, so we need to do it here.
+ */
+ if (s->ctor)
+ kmemcheck_mark_uninitialized_pages(page, pages);
+ else
+ kmemcheck_mark_unallocated_pages(page, pages);
+}
+
+void kmemcheck_free_shadow(struct kmem_cache *s, struct page *page, int order)
+{
+ struct page *shadow;
+ int pages;
+ int i;
+
+ pages = 1 << order;
+
+ kmemcheck_show_pages(page, pages);
+
+ shadow = virt_to_page(page[0].shadow);
+
+ for(i = 0; i < pages; ++i)
+ page[i].shadow = NULL;
+
+ __free_pages(shadow, order);
+}
+
+void kmemcheck_slab_alloc(struct kmem_cache *s, gfp_t gfpflags, void *object,
+ size_t size)
+{
+ /*
+ * Has already been memset(), which initializes the shadow for us
+ * as well.
+ */
+ if (gfpflags & __GFP_ZERO)
+ return;
+
+ /* No need to initialize the shadow of a non-tracked slab. */
+ if (s->flags & SLAB_NOTRACK)
+ return;
+
+ if (!kmemcheck_enabled || gfpflags & __GFP_NOTRACK) {
+ /*
+ * Allow notracked objects to be allocated from
+ * tracked caches. Note however that these objects
+ * will still get page faults on access, they just
+ * won't ever be flagged as uninitialized. If page
+ * faults are not acceptable, the slab cache itself
+ * should be marked NOTRACK.
+ */
+ kmemcheck_mark_initialized(object, size);
+ } else if (!s->ctor) {
+ /*
+ * New objects should be marked uninitialized before
+ * they're returned to the called.
+ */
+ kmemcheck_mark_uninitialized(object, size);
+ }
+}
+
+void kmemcheck_slab_free(struct kmem_cache *s, void *object, size_t size)
+{
+ /* TODO: RCU freeing is unsupported for now; hide false positives. */
+ if (!s->ctor && !(s->flags & SLAB_DESTROY_BY_RCU))
+ kmemcheck_mark_freed(object, size);
+}
projects / platform / kernel / linux-exynos.git / commitdiff