Files
Astral/kernel-src/include/kernel/kcov.h
T
Matheus e4a4896b4b kcov: initial implementation
Implement a device (/dev/kcov) that exposes coverage info for the
kernel. This will be especially useful for coverage-based fuzzing (e.g.
syzkaller).

Exclude a lot of functions which would crash/otherwise interfere in the
coverage, including only processing coverage callbacks when not handling
an irq.
2026-10-06 11:51:02 -03:00

44 lines
1.0 KiB
C

#ifndef _KCOV_H
#define _KCOV_H
#include <stdint.h>
#include <stddef.h>
#include <mutex.h>
#ifdef KCOV_ENABLED
#define KCOV_DISABLED __attribute__((no_sanitize_coverage))
#else
#define KCOV_DISABLED
#endif
#define KCOV_MODE_DISABLED 0
#define KCOV_MODE_PC 1
#define KCOV_MODE_CMP 2
#define KCOV_CMP_FLAGS_CONST 1
#define KCOV_CMP_FLAGS_8BIT 0
#define KCOV_CMP_FLAGS_16BIT 2
#define KCOV_CMP_FLAGS_32BIT 4
#define KCOV_CMP_FLAGS_64BIT 6
typedef struct {
unsigned int mode;
mutex_t mapping_mutex;
unsigned int entry_count; // protected by mutex
uint64_t *buffer; // pointer protected by mutex
size_t mappings; // protected by mutex
unsigned int refcount;
unsigned int minor;
void *vnode_handle;
} kcov_t;
void kcov_publish_pc(uint64_t pc);
void kcov_publish_cmp(uint64_t pc, uint64_t v1, uint64_t v2, uint64_t flags);
int kcov_set_buffer_size(unsigned int entry_count);
int kcov_set_mode(unsigned int mode);
void kcov_hold(kcov_t *kcov);
void kcov_release(kcov_t *kcov);
void kcov_free_buffer(kcov_t *kcov);
#endif