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-rw-r--r--include/linux/stackleak.h89
1 files changed, 0 insertions, 89 deletions
diff --git a/include/linux/stackleak.h b/include/linux/stackleak.h
deleted file mode 100644
index 3be2cb564710..000000000000
--- a/include/linux/stackleak.h
+++ /dev/null
@@ -1,89 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _LINUX_STACKLEAK_H
-#define _LINUX_STACKLEAK_H
-
-#include <linux/sched.h>
-#include <linux/sched/task_stack.h>
-
-/*
- * Check that the poison value points to the unused hole in the
- * virtual memory map for your platform.
- */
-#define STACKLEAK_POISON -0xBEEF
-#define STACKLEAK_SEARCH_DEPTH 128
-
-#ifdef CONFIG_GCC_PLUGIN_STACKLEAK
-#include <asm/stacktrace.h>
-#include <linux/linkage.h>
-
-/*
- * The lowest address on tsk's stack which we can plausibly erase.
- */
-static __always_inline unsigned long
-stackleak_task_low_bound(const struct task_struct *tsk)
-{
- /*
- * The lowest unsigned long on the task stack contains STACK_END_MAGIC,
- * which we must not corrupt.
- */
- return (unsigned long)end_of_stack(tsk) + sizeof(unsigned long);
-}
-
-/*
- * The address immediately after the highest address on tsk's stack which we
- * can plausibly erase.
- */
-static __always_inline unsigned long
-stackleak_task_high_bound(const struct task_struct *tsk)
-{
- /*
- * The task's pt_regs lives at the top of the task stack and will be
- * overwritten by exception entry, so there's no need to erase them.
- */
- return (unsigned long)task_pt_regs(tsk);
-}
-
-/*
- * Find the address immediately above the poisoned region of the stack, where
- * that region falls between 'low' (inclusive) and 'high' (exclusive).
- */
-static __always_inline unsigned long
-stackleak_find_top_of_poison(const unsigned long low, const unsigned long high)
-{
- const unsigned int depth = STACKLEAK_SEARCH_DEPTH / sizeof(unsigned long);
- unsigned int poison_count = 0;
- unsigned long poison_high = high;
- unsigned long sp = high;
-
- while (sp > low && poison_count < depth) {
- sp -= sizeof(unsigned long);
-
- if (*(unsigned long *)sp == STACKLEAK_POISON) {
- poison_count++;
- } else {
- poison_count = 0;
- poison_high = sp;
- }
- }
-
- return poison_high;
-}
-
-static inline void stackleak_task_init(struct task_struct *t)
-{
- t->lowest_stack = stackleak_task_low_bound(t);
-# ifdef CONFIG_STACKLEAK_METRICS
- t->prev_lowest_stack = t->lowest_stack;
-# endif
-}
-
-asmlinkage void noinstr stackleak_erase(void);
-asmlinkage void noinstr stackleak_erase_on_task_stack(void);
-asmlinkage void noinstr stackleak_erase_off_task_stack(void);
-void __no_caller_saved_registers noinstr stackleak_track_stack(void);
-
-#else /* !CONFIG_GCC_PLUGIN_STACKLEAK */
-static inline void stackleak_task_init(struct task_struct *t) { }
-#endif
-
-#endif