kasan: remove __kasan_unpoison_stack

There's no need for __kasan_unpoison_stack() helper, as it's only
currently used in a single place. Removing it also removes unneeded
arithmetic.

No functional changes.

Link: https://lkml.kernel.org/r/93e78948704a42ea92f6248ff8a725613d721161.1606162397.git.andreyknvl@google.com
Link: https://linux-review.googlesource.com/id/Ie5ba549d445292fe629b4a96735e4034957bcc50
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 2754ce0..b71dfe7 100644 (file)
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -64,18 +64,12 @@ void kasan_unpoison_range(const void *address, size_t size)
 }
 
 #if CONFIG_KASAN_STACK
-static void __kasan_unpoison_stack(struct task_struct *task, const void *sp)
-{
-       void *base = task_stack_page(task);
-       size_t size = sp - base;
-
-       unpoison_range(base, size);
-}
-
 /* Unpoison the entire stack for a task. */
 void kasan_unpoison_task_stack(struct task_struct *task)
 {
-       __kasan_unpoison_stack(task, task_stack_page(task) + THREAD_SIZE);
+       void *base = task_stack_page(task);
+
+       unpoison_range(base, THREAD_SIZE);
 }
 
 /* Unpoison the stack for the current task beyond a watermark sp value. */