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[023/262] kasan: generic: introduce kasan_record_aux_stack_noalloc()

Message ID 20211105203546.DpiM4aEip%akpm@linux-foundation.org (mailing list archive)
State New
Headers show
Series [001/262] scripts/spelling.txt: add more spellings to spelling.txt | expand

Commit Message

Andrew Morton Nov. 5, 2021, 8:35 p.m. UTC 
From: Marco Elver <elver@google.com>
Subject: kasan: generic: introduce kasan_record_aux_stack_noalloc()

Introduce a variant of kasan_record_aux_stack() that does not do any
memory allocation through stackdepot.  This will permit using it in
contexts that cannot allocate any memory.

Link: https://lkml.kernel.org/r/20210913112609.2651084-6-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Tested-by: Shuah Khan <skhan@linuxfoundation.org>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Taras Madan <tarasmadan@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vijayanand Jitta <vjitta@codeaurora.org>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Cc: Walter Wu <walter-zh.wu@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/kasan.h |    2 ++
 mm/kasan/generic.c    |   14 ++++++++++++--
 2 files changed, 14 insertions(+), 2 deletions(-)
diff mbox series

Patch

--- a/include/linux/kasan.h~kasan-generic-introduce-kasan_record_aux_stack_noalloc
+++ a/include/linux/kasan.h
@@ -370,12 +370,14 @@  static inline void kasan_unpoison_task_s
 void kasan_cache_shrink(struct kmem_cache *cache);
 void kasan_cache_shutdown(struct kmem_cache *cache);
 void kasan_record_aux_stack(void *ptr);
+void kasan_record_aux_stack_noalloc(void *ptr);
 
 #else /* CONFIG_KASAN_GENERIC */
 
 static inline void kasan_cache_shrink(struct kmem_cache *cache) {}
 static inline void kasan_cache_shutdown(struct kmem_cache *cache) {}
 static inline void kasan_record_aux_stack(void *ptr) {}
+static inline void kasan_record_aux_stack_noalloc(void *ptr) {}
 
 #endif /* CONFIG_KASAN_GENERIC */
 
--- a/mm/kasan/generic.c~kasan-generic-introduce-kasan_record_aux_stack_noalloc
+++ a/mm/kasan/generic.c
@@ -328,7 +328,7 @@  DEFINE_ASAN_SET_SHADOW(f3);
 DEFINE_ASAN_SET_SHADOW(f5);
 DEFINE_ASAN_SET_SHADOW(f8);
 
-void kasan_record_aux_stack(void *addr)
+static void __kasan_record_aux_stack(void *addr, bool can_alloc)
 {
 	struct page *page = kasan_addr_to_page(addr);
 	struct kmem_cache *cache;
@@ -345,7 +345,17 @@  void kasan_record_aux_stack(void *addr)
 		return;
 
 	alloc_meta->aux_stack[1] = alloc_meta->aux_stack[0];
-	alloc_meta->aux_stack[0] = kasan_save_stack(GFP_NOWAIT, true);
+	alloc_meta->aux_stack[0] = kasan_save_stack(GFP_NOWAIT, can_alloc);
+}
+
+void kasan_record_aux_stack(void *addr)
+{
+	return __kasan_record_aux_stack(addr, true);
+}
+
+void kasan_record_aux_stack_noalloc(void *addr)
+{
+	return __kasan_record_aux_stack(addr, false);
 }
 
 void kasan_set_free_info(struct kmem_cache *cache,