kmemleak: clear stale pointers from task stacks
Kmemleak considers any pointers on task stacks as references. This
patch clears newly allocated and reused vmap stacks.
Link: http://lkml.kernel.org/r/150728990124.744199.8403409836394318684.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/fork.c b/kernel/fork.c
index e702cb9f..07cc743 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -215,6 +215,10 @@
if (!s)
continue;
+#ifdef CONFIG_DEBUG_KMEMLEAK
+ /* Clear stale pointers from reused stack. */
+ memset(s->addr, 0, THREAD_SIZE);
+#endif
tsk->stack_vm_area = s;
return s->addr;
}