diff mbox series

[v8,01/20] kasan, mm: change hooks signatures

Message ID 8b30f2d3e325de843f892e32f076fe9cc726191d.1537383101.git.andreyknvl@google.com (mailing list archive)
State New, archived
Headers show
Series kasan: add software tag-based mode for arm64 | expand

Commit Message

Andrey Konovalov Sept. 19, 2018, 6:54 p.m. UTC 
Tag-based KASAN changes the value of the top byte of pointers returned
from the kernel allocation functions (such as kmalloc). This patch updates
KASAN hooks signatures and their usage in SLAB and SLUB code to reflect
that.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
 include/linux/kasan.h | 43 +++++++++++++++++++++++++++++--------------
 mm/kasan/kasan.c      | 30 ++++++++++++++++++------------
 mm/slab.c             | 12 ++++++------
 mm/slab.h             |  2 +-
 mm/slab_common.c      |  4 ++--
 mm/slub.c             | 15 +++++++--------
 6 files changed, 63 insertions(+), 43 deletions(-)

Comments

kernel test robot Sept. 21, 2018, 4:05 a.m. UTC | #1 
Hi Andrey,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on v4.19-rc4 next-20180919]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Andrey-Konovalov/kasan-add-software-tag-based-mode-for-arm64/20180920-172444
config: x86_64-randconfig-x013-201837 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All errors (new ones prefixed by >>):

   In file included from include/linux/slab.h:129:0,
                    from include/linux/crypto.h:24,
                    from arch/x86/kernel/asm-offsets.c:9:
   include/linux/kasan.h: In function 'kasan_init_slab_obj':
>> include/linux/kasan.h:111:9: error: 'ptr' undeclared (first use in this function)
     return ptr;
            ^~~
   include/linux/kasan.h:111:9: note: each undeclared identifier is reported only once for each function it appears in
   make[2]: *** [arch/x86/kernel/asm-offsets.s] Error 1
   make[2]: Target '__build' not remade because of errors.
   make[1]: *** [prepare0] Error 2
   make[1]: Target 'prepare' not remade because of errors.
   make: *** [sub-make] Error 2

vim +/ptr +111 include/linux/kasan.h

   102	
   103	static inline void kasan_poison_slab(struct page *page) {}
   104	static inline void kasan_unpoison_object_data(struct kmem_cache *cache,
   105						void *object) {}
   106	static inline void kasan_poison_object_data(struct kmem_cache *cache,
   107						void *object) {}
   108	static inline void *kasan_init_slab_obj(struct kmem_cache *cache,
   109					const void *object)
   110	{
 > 111		return ptr;
   112	}
   113	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
kernel test robot Sept. 21, 2018, 7:03 a.m. UTC | #2 
Hi Andrey,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on v4.19-rc4 next-20180919]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Andrey-Konovalov/kasan-add-software-tag-based-mode-for-arm64/20180920-172444
config: microblaze-mmu_defconfig (attached as .config)
compiler: microblaze-linux-gcc (GCC) 8.1.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        GCC_VERSION=8.1.0 make.cross ARCH=microblaze 

All errors (new ones prefixed by >>):

   In file included from include/linux/slab.h:129,
                    from include/linux/irq.h:21,
                    from include/asm-generic/hardirq.h:13,
                    from ./arch/microblaze/include/generated/asm/hardirq.h:1,
                    from include/linux/hardirq.h:9,
                    from include/linux/interrupt.h:11,
                    from include/linux/kernel_stat.h:9,
                    from arch/microblaze/kernel/asm-offsets.c:14:
   include/linux/kasan.h: In function 'kasan_init_slab_obj':
>> include/linux/kasan.h:111:9: error: 'ptr' undeclared (first use in this function); did you mean 'qstr'?
     return ptr;
            ^~~
            qstr
   include/linux/kasan.h:111:9: note: each undeclared identifier is reported only once for each function it appears in
   make[2]: *** [arch/microblaze/kernel/asm-offsets.s] Error 1
   make[2]: Target '__build' not remade because of errors.
   make[1]: *** [prepare0] Error 2
   make[1]: Target 'prepare' not remade because of errors.
   make: *** [sub-make] Error 2

vim +111 include/linux/kasan.h

   102	
   103	static inline void kasan_poison_slab(struct page *page) {}
   104	static inline void kasan_unpoison_object_data(struct kmem_cache *cache,
   105						void *object) {}
   106	static inline void kasan_poison_object_data(struct kmem_cache *cache,
   107						void *object) {}
   108	static inline void *kasan_init_slab_obj(struct kmem_cache *cache,
   109					const void *object)
   110	{
 > 111		return ptr;
   112	}
   113	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
Andrey Konovalov Sept. 21, 2018, 12:13 p.m. UTC | #3 
On Fri, Sep 21, 2018 at 6:05 AM, kbuild test robot <lkp@intel.com> wrote:
> Hi Andrey,
>
> Thank you for the patch! Yet something to improve:
>
> [auto build test ERROR on linus/master]
> [also build test ERROR on v4.19-rc4 next-20180919]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>
> url:    https://github.com/0day-ci/linux/commits/Andrey-Konovalov/kasan-add-software-tag-based-mode-for-arm64/20180920-172444
> config: x86_64-randconfig-x013-201837 (attached as .config)
> compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
> reproduce:
>         # save the attached .config to linux build tree
>         make ARCH=x86_64
>
> All errors (new ones prefixed by >>):
>
>    In file included from include/linux/slab.h:129:0,
>                     from include/linux/crypto.h:24,
>                     from arch/x86/kernel/asm-offsets.c:9:
>    include/linux/kasan.h: In function 'kasan_init_slab_obj':
>>> include/linux/kasan.h:111:9: error: 'ptr' undeclared (first use in this function)
>      return ptr;
>             ^~~

Right, will fix in v9.

>    include/linux/kasan.h:111:9: note: each undeclared identifier is reported only once for each function it appears in
>    make[2]: *** [arch/x86/kernel/asm-offsets.s] Error 1
>    make[2]: Target '__build' not remade because of errors.
>    make[1]: *** [prepare0] Error 2
>    make[1]: Target 'prepare' not remade because of errors.
>    make: *** [sub-make] Error 2
>
> vim +/ptr +111 include/linux/kasan.h
>
>    102
>    103  static inline void kasan_poison_slab(struct page *page) {}
>    104  static inline void kasan_unpoison_object_data(struct kmem_cache *cache,
>    105                                          void *object) {}
>    106  static inline void kasan_poison_object_data(struct kmem_cache *cache,
>    107                                          void *object) {}
>    108  static inline void *kasan_init_slab_obj(struct kmem_cache *cache,
>    109                                  const void *object)
>    110  {
>  > 111          return ptr;
>    112  }
>    113
>
> ---
> 0-DAY kernel test infrastructure                Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
>
> --
> You received this message because you are subscribed to the Google Groups "kasan-dev" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@googlegroups.com.
> To post to this group, send email to kasan-dev@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/201809211218.10PA6RGy%25fengguang.wu%40intel.com.
> For more options, visit https://groups.google.com/d/optout.
diff mbox series

Patch

diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index 46aae129917c..3b019db87892 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -51,16 +51,16 @@  void kasan_cache_shutdown(struct kmem_cache *cache);
 void kasan_poison_slab(struct page *page);
 void kasan_unpoison_object_data(struct kmem_cache *cache, void *object);
 void kasan_poison_object_data(struct kmem_cache *cache, void *object);
-void kasan_init_slab_obj(struct kmem_cache *cache, const void *object);
+void *kasan_init_slab_obj(struct kmem_cache *cache, const void *object);
 
-void kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags);
+void *kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags);
 void kasan_kfree_large(void *ptr, unsigned long ip);
 void kasan_poison_kfree(void *ptr, unsigned long ip);
-void kasan_kmalloc(struct kmem_cache *s, const void *object, size_t size,
+void *kasan_kmalloc(struct kmem_cache *s, const void *object, size_t size,
 		  gfp_t flags);
-void kasan_krealloc(const void *object, size_t new_size, gfp_t flags);
+void *kasan_krealloc(const void *object, size_t new_size, gfp_t flags);
 
-void kasan_slab_alloc(struct kmem_cache *s, void *object, gfp_t flags);
+void *kasan_slab_alloc(struct kmem_cache *s, void *object, gfp_t flags);
 bool kasan_slab_free(struct kmem_cache *s, void *object, unsigned long ip);
 
 struct kasan_cache {
@@ -105,19 +105,34 @@  static inline void kasan_unpoison_object_data(struct kmem_cache *cache,
 					void *object) {}
 static inline void kasan_poison_object_data(struct kmem_cache *cache,
 					void *object) {}
-static inline void kasan_init_slab_obj(struct kmem_cache *cache,
-				const void *object) {}
+static inline void *kasan_init_slab_obj(struct kmem_cache *cache,
+				const void *object)
+{
+	return ptr;
+}
 
-static inline void kasan_kmalloc_large(void *ptr, size_t size, gfp_t flags) {}
+static inline void *kasan_kmalloc_large(void *ptr, size_t size, gfp_t flags)
+{
+	return ptr;
+}
 static inline void kasan_kfree_large(void *ptr, unsigned long ip) {}
 static inline void kasan_poison_kfree(void *ptr, unsigned long ip) {}
-static inline void kasan_kmalloc(struct kmem_cache *s, const void *object,
-				size_t size, gfp_t flags) {}
-static inline void kasan_krealloc(const void *object, size_t new_size,
-				 gfp_t flags) {}
+static inline void *kasan_kmalloc(struct kmem_cache *s, const void *object,
+				size_t size, gfp_t flags)
+{
+	return (void *)object;
+}
+static inline void *kasan_krealloc(const void *object, size_t new_size,
+				 gfp_t flags)
+{
+	return (void *)object;
+}
 
-static inline void kasan_slab_alloc(struct kmem_cache *s, void *object,
-				   gfp_t flags) {}
+static inline void *kasan_slab_alloc(struct kmem_cache *s, void *object,
+				   gfp_t flags)
+{
+	return object;
+}
 static inline bool kasan_slab_free(struct kmem_cache *s, void *object,
 				   unsigned long ip)
 {
diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c
index c3bd5209da38..55deff17a4d9 100644
--- a/mm/kasan/kasan.c
+++ b/mm/kasan/kasan.c
@@ -474,20 +474,22 @@  struct kasan_free_meta *get_free_info(struct kmem_cache *cache,
 	return (void *)object + cache->kasan_info.free_meta_offset;
 }
 
-void kasan_init_slab_obj(struct kmem_cache *cache, const void *object)
+void *kasan_init_slab_obj(struct kmem_cache *cache, const void *object)
 {
 	struct kasan_alloc_meta *alloc_info;
 
 	if (!(cache->flags & SLAB_KASAN))
-		return;
+		return (void *)object;
 
 	alloc_info = get_alloc_info(cache, object);
 	__memset(alloc_info, 0, sizeof(*alloc_info));
+
+	return (void *)object;
 }
 
-void kasan_slab_alloc(struct kmem_cache *cache, void *object, gfp_t flags)
+void *kasan_slab_alloc(struct kmem_cache *cache, void *object, gfp_t flags)
 {
-	kasan_kmalloc(cache, object, cache->object_size, flags);
+	return kasan_kmalloc(cache, object, cache->object_size, flags);
 }
 
 static bool __kasan_slab_free(struct kmem_cache *cache, void *object,
@@ -528,7 +530,7 @@  bool kasan_slab_free(struct kmem_cache *cache, void *object, unsigned long ip)
 	return __kasan_slab_free(cache, object, ip, true);
 }
 
-void kasan_kmalloc(struct kmem_cache *cache, const void *object, size_t size,
+void *kasan_kmalloc(struct kmem_cache *cache, const void *object, size_t size,
 		   gfp_t flags)
 {
 	unsigned long redzone_start;
@@ -538,7 +540,7 @@  void kasan_kmalloc(struct kmem_cache *cache, const void *object, size_t size,
 		quarantine_reduce();
 
 	if (unlikely(object == NULL))
-		return;
+		return NULL;
 
 	redzone_start = round_up((unsigned long)(object + size),
 				KASAN_SHADOW_SCALE_SIZE);
@@ -551,10 +553,12 @@  void kasan_kmalloc(struct kmem_cache *cache, const void *object, size_t size,
 
 	if (cache->flags & SLAB_KASAN)
 		set_track(&get_alloc_info(cache, object)->alloc_track, flags);
+
+	return (void *)object;
 }
 EXPORT_SYMBOL(kasan_kmalloc);
 
-void kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags)
+void *kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags)
 {
 	struct page *page;
 	unsigned long redzone_start;
@@ -564,7 +568,7 @@  void kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags)
 		quarantine_reduce();
 
 	if (unlikely(ptr == NULL))
-		return;
+		return NULL;
 
 	page = virt_to_page(ptr);
 	redzone_start = round_up((unsigned long)(ptr + size),
@@ -574,21 +578,23 @@  void kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags)
 	kasan_unpoison_shadow(ptr, size);
 	kasan_poison_shadow((void *)redzone_start, redzone_end - redzone_start,
 		KASAN_PAGE_REDZONE);
+
+	return (void *)ptr;
 }
 
-void kasan_krealloc(const void *object, size_t size, gfp_t flags)
+void *kasan_krealloc(const void *object, size_t size, gfp_t flags)
 {
 	struct page *page;
 
 	if (unlikely(object == ZERO_SIZE_PTR))
-		return;
+		return ZERO_SIZE_PTR;
 
 	page = virt_to_head_page(object);
 
 	if (unlikely(!PageSlab(page)))
-		kasan_kmalloc_large(object, size, flags);
+		return kasan_kmalloc_large(object, size, flags);
 	else
-		kasan_kmalloc(page->slab_cache, object, size, flags);
+		return kasan_kmalloc(page->slab_cache, object, size, flags);
 }
 
 void kasan_poison_kfree(void *ptr, unsigned long ip)
diff --git a/mm/slab.c b/mm/slab.c
index aa76a70e087e..6fdca9ec2ea4 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3551,7 +3551,7 @@  void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags)
 {
 	void *ret = slab_alloc(cachep, flags, _RET_IP_);
 
-	kasan_slab_alloc(cachep, ret, flags);
+	ret = kasan_slab_alloc(cachep, ret, flags);
 	trace_kmem_cache_alloc(_RET_IP_, ret,
 			       cachep->object_size, cachep->size, flags);
 
@@ -3617,7 +3617,7 @@  kmem_cache_alloc_trace(struct kmem_cache *cachep, gfp_t flags, size_t size)
 
 	ret = slab_alloc(cachep, flags, _RET_IP_);
 
-	kasan_kmalloc(cachep, ret, size, flags);
+	ret = kasan_kmalloc(cachep, ret, size, flags);
 	trace_kmalloc(_RET_IP_, ret,
 		      size, cachep->size, flags);
 	return ret;
@@ -3641,7 +3641,7 @@  void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid)
 {
 	void *ret = slab_alloc_node(cachep, flags, nodeid, _RET_IP_);
 
-	kasan_slab_alloc(cachep, ret, flags);
+	ret = kasan_slab_alloc(cachep, ret, flags);
 	trace_kmem_cache_alloc_node(_RET_IP_, ret,
 				    cachep->object_size, cachep->size,
 				    flags, nodeid);
@@ -3660,7 +3660,7 @@  void *kmem_cache_alloc_node_trace(struct kmem_cache *cachep,
 
 	ret = slab_alloc_node(cachep, flags, nodeid, _RET_IP_);
 
-	kasan_kmalloc(cachep, ret, size, flags);
+	ret = kasan_kmalloc(cachep, ret, size, flags);
 	trace_kmalloc_node(_RET_IP_, ret,
 			   size, cachep->size,
 			   flags, nodeid);
@@ -3679,7 +3679,7 @@  __do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller)
 	if (unlikely(ZERO_OR_NULL_PTR(cachep)))
 		return cachep;
 	ret = kmem_cache_alloc_node_trace(cachep, flags, node, size);
-	kasan_kmalloc(cachep, ret, size, flags);
+	ret = kasan_kmalloc(cachep, ret, size, flags);
 
 	return ret;
 }
@@ -3715,7 +3715,7 @@  static __always_inline void *__do_kmalloc(size_t size, gfp_t flags,
 		return cachep;
 	ret = slab_alloc(cachep, flags, caller);
 
-	kasan_kmalloc(cachep, ret, size, flags);
+	ret = kasan_kmalloc(cachep, ret, size, flags);
 	trace_kmalloc(caller, ret,
 		      size, cachep->size, flags);
 
diff --git a/mm/slab.h b/mm/slab.h
index 58c6c1c2a78e..4190c24ef0e9 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -441,7 +441,7 @@  static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags,
 
 		kmemleak_alloc_recursive(object, s->object_size, 1,
 					 s->flags, flags);
-		kasan_slab_alloc(s, object, flags);
+		p[i] = kasan_slab_alloc(s, object, flags);
 	}
 
 	if (memcg_kmem_enabled())
diff --git a/mm/slab_common.c b/mm/slab_common.c
index fea3376f9816..3abfa0f86118 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -1183,7 +1183,7 @@  void *kmalloc_order(size_t size, gfp_t flags, unsigned int order)
 	page = alloc_pages(flags, order);
 	ret = page ? page_address(page) : NULL;
 	kmemleak_alloc(ret, size, 1, flags);
-	kasan_kmalloc_large(ret, size, flags);
+	ret = kasan_kmalloc_large(ret, size, flags);
 	return ret;
 }
 EXPORT_SYMBOL(kmalloc_order);
@@ -1461,7 +1461,7 @@  static __always_inline void *__do_krealloc(const void *p, size_t new_size,
 		ks = ksize(p);
 
 	if (ks >= new_size) {
-		kasan_krealloc((void *)p, new_size, flags);
+		p = kasan_krealloc((void *)p, new_size, flags);
 		return (void *)p;
 	}
 
diff --git a/mm/slub.c b/mm/slub.c
index 8da34a8af53d..b2172284d421 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1334,10 +1334,10 @@  static inline void dec_slabs_node(struct kmem_cache *s, int node,
  * Hooks for other subsystems that check memory allocations. In a typical
  * production configuration these hooks all should produce no code at all.
  */
-static inline void kmalloc_large_node_hook(void *ptr, size_t size, gfp_t flags)
+static inline void *kmalloc_large_node_hook(void *ptr, size_t size, gfp_t flags)
 {
 	kmemleak_alloc(ptr, size, 1, flags);
-	kasan_kmalloc_large(ptr, size, flags);
+	return kasan_kmalloc_large(ptr, size, flags);
 }
 
 static __always_inline void kfree_hook(void *x)
@@ -2730,7 +2730,7 @@  void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size)
 {
 	void *ret = slab_alloc(s, gfpflags, _RET_IP_);
 	trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags);
-	kasan_kmalloc(s, ret, size, gfpflags);
+	ret = kasan_kmalloc(s, ret, size, gfpflags);
 	return ret;
 }
 EXPORT_SYMBOL(kmem_cache_alloc_trace);
@@ -2758,7 +2758,7 @@  void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
 	trace_kmalloc_node(_RET_IP_, ret,
 			   size, s->size, gfpflags, node);
 
-	kasan_kmalloc(s, ret, size, gfpflags);
+	ret = kasan_kmalloc(s, ret, size, gfpflags);
 	return ret;
 }
 EXPORT_SYMBOL(kmem_cache_alloc_node_trace);
@@ -3748,7 +3748,7 @@  void *__kmalloc(size_t size, gfp_t flags)
 
 	trace_kmalloc(_RET_IP_, ret, size, s->size, flags);
 
-	kasan_kmalloc(s, ret, size, flags);
+	ret = kasan_kmalloc(s, ret, size, flags);
 
 	return ret;
 }
@@ -3765,8 +3765,7 @@  static void *kmalloc_large_node(size_t size, gfp_t flags, int node)
 	if (page)
 		ptr = page_address(page);
 
-	kmalloc_large_node_hook(ptr, size, flags);
-	return ptr;
+	return kmalloc_large_node_hook(ptr, size, flags);
 }
 
 void *__kmalloc_node(size_t size, gfp_t flags, int node)
@@ -3793,7 +3792,7 @@  void *__kmalloc_node(size_t size, gfp_t flags, int node)
 
 	trace_kmalloc_node(_RET_IP_, ret, size, s->size, flags, node);
 
-	kasan_kmalloc(s, ret, size, flags);
+	ret = kasan_kmalloc(s, ret, size, flags);
 
 	return ret;
 }