linux_dsm_epyc7002/arch/x86/include/asm/kprobes.h
Masami Hiramatsu b4da3340ea tracing/kprobe: bpf: Check error injectable event is on function entry
Check whether error injectable event is on function entry or not.
Currently it checks the event is ftrace-based kprobes or not,
but that is wrong. It should check if the event is on the entry
of target function. Since error injection will override a function
to just return with modified return value, that operation must
be done before the target function starts making stackframe.

As a side effect, bpf error injection is no need to depend on
function-tracer. It can work with sw-breakpoint based kprobe
events too.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-12 17:33:37 -08:00

128 lines
3.9 KiB
C

#ifndef _ASM_X86_KPROBES_H
#define _ASM_X86_KPROBES_H
/*
* Kernel Probes (KProbes)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Copyright (C) IBM Corporation, 2002, 2004
*
* See arch/x86/kernel/kprobes.c for x86 kprobes history.
*/
#include <asm-generic/kprobes.h>
#define BREAKPOINT_INSTRUCTION 0xcc
#ifdef CONFIG_KPROBES
#include <linux/types.h>
#include <linux/ptrace.h>
#include <linux/percpu.h>
#include <asm/insn.h>
#define __ARCH_WANT_KPROBES_INSN_SLOT
struct pt_regs;
struct kprobe;
typedef u8 kprobe_opcode_t;
#define RELATIVEJUMP_OPCODE 0xe9
#define RELATIVEJUMP_SIZE 5
#define RELATIVECALL_OPCODE 0xe8
#define RELATIVE_ADDR_SIZE 4
#define MAX_STACK_SIZE 64
#define CUR_STACK_SIZE(ADDR) \
(current_top_of_stack() - (unsigned long)(ADDR))
#define MIN_STACK_SIZE(ADDR) \
(MAX_STACK_SIZE < CUR_STACK_SIZE(ADDR) ? \
MAX_STACK_SIZE : CUR_STACK_SIZE(ADDR))
#define flush_insn_slot(p) do { } while (0)
/* optinsn template addresses */
extern __visible kprobe_opcode_t optprobe_template_entry[];
extern __visible kprobe_opcode_t optprobe_template_val[];
extern __visible kprobe_opcode_t optprobe_template_call[];
extern __visible kprobe_opcode_t optprobe_template_end[];
#define MAX_OPTIMIZED_LENGTH (MAX_INSN_SIZE + RELATIVE_ADDR_SIZE)
#define MAX_OPTINSN_SIZE \
(((unsigned long)optprobe_template_end - \
(unsigned long)optprobe_template_entry) + \
MAX_OPTIMIZED_LENGTH + RELATIVEJUMP_SIZE)
extern const int kretprobe_blacklist_size;
void arch_remove_kprobe(struct kprobe *p);
asmlinkage void kretprobe_trampoline(void);
extern void arch_kprobe_override_function(struct pt_regs *regs);
/* Architecture specific copy of original instruction*/
struct arch_specific_insn {
/* copy of the original instruction */
kprobe_opcode_t *insn;
/*
* boostable = false: This instruction type is not boostable.
* boostable = true: This instruction has been boosted: we have
* added a relative jump after the instruction copy in insn,
* so no single-step and fixup are needed (unless there's
* a post_handler or break_handler).
*/
bool boostable;
bool if_modifier;
};
struct arch_optimized_insn {
/* copy of the original instructions */
kprobe_opcode_t copied_insn[RELATIVE_ADDR_SIZE];
/* detour code buffer */
kprobe_opcode_t *insn;
/* the size of instructions copied to detour code buffer */
size_t size;
};
/* Return true (!0) if optinsn is prepared for optimization. */
static inline int arch_prepared_optinsn(struct arch_optimized_insn *optinsn)
{
return optinsn->size;
}
struct prev_kprobe {
struct kprobe *kp;
unsigned long status;
unsigned long old_flags;
unsigned long saved_flags;
};
/* per-cpu kprobe control block */
struct kprobe_ctlblk {
unsigned long kprobe_status;
unsigned long kprobe_old_flags;
unsigned long kprobe_saved_flags;
unsigned long *jprobe_saved_sp;
struct pt_regs jprobe_saved_regs;
kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
struct prev_kprobe prev_kprobe;
};
extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
extern int kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data);
extern int kprobe_int3_handler(struct pt_regs *regs);
extern int kprobe_debug_handler(struct pt_regs *regs);
#endif /* CONFIG_KPROBES */
#endif /* _ASM_X86_KPROBES_H */