kernel_optimize_test/include/linux/stackleak.h
Alexander Popov 964c9dff00 stackleak: Allow runtime disabling of kernel stack erasing
Introduce CONFIG_STACKLEAK_RUNTIME_DISABLE option, which provides
'stack_erasing' sysctl. It can be used in runtime to control kernel
stack erasing for kernels built with CONFIG_GCC_PLUGIN_STACKLEAK.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Alexander Popov <alex.popov@linux.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2018-09-04 10:35:48 -07:00

36 lines
909 B
C

/* 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>
static inline void stackleak_task_init(struct task_struct *t)
{
t->lowest_stack = (unsigned long)end_of_stack(t) + sizeof(unsigned long);
# ifdef CONFIG_STACKLEAK_METRICS
t->prev_lowest_stack = t->lowest_stack;
# endif
}
#ifdef CONFIG_STACKLEAK_RUNTIME_DISABLE
int stack_erasing_sysctl(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos);
#endif
#else /* !CONFIG_GCC_PLUGIN_STACKLEAK */
static inline void stackleak_task_init(struct task_struct *t) { }
#endif
#endif