Commit 540adea3 authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Alexei Starovoitov
Browse files

error-injection: Separate error-injection from kprobe 



Since error-injection framework is not limited to be used
by kprobes, nor bpf. Other kernel subsystems can use it
freely for checking safeness of error-injection, e.g.
livepatch, ftrace etc.
So this separate error-injection framework from kprobes.

Some differences has been made:

- "kprobe" word is removed from any APIs/structures.
- BPF_ALLOW_ERROR_INJECTION() is renamed to
  ALLOW_ERROR_INJECTION() since it is not limited for BPF too.
- CONFIG_FUNCTION_ERROR_INJECTION is the config item of this
  feature. It is automatically enabled if the arch supports
  error injection feature for kprobe or ftrace etc.

Signed-off-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: default avatarJosef Bacik <jbacik@fb.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 66665ad2

arch/Kconfig

+1 −1
Original line number Diff line number Diff line
@@ -196,7 +196,7 @@ config HAVE_OPTPROBES 
config HAVE_KPROBES_ON_FTRACE

	bool



config HAVE_KPROBE_OVERRIDE

config HAVE_FUNCTION_ERROR_INJECTION

	bool



config HAVE_NMI

arch/x86/Kconfig

+1 −1
Original line number Diff line number Diff line
@@ -154,7 +154,7 @@ config X86 
	select HAVE_KERNEL_XZ

	select HAVE_KPROBES

	select HAVE_KPROBES_ON_FTRACE

	select HAVE_KPROBE_OVERRIDE

	select HAVE_FUNCTION_ERROR_INJECTION

	select HAVE_KRETPROBES

	select HAVE_KVM

	select HAVE_LIVEPATCH			if X86_64

arch/x86/include/asm/error-injection.h

0 → 100644
+13 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef _ASM_ERROR_INJECTION_H

#define _ASM_ERROR_INJECTION_H



#include <linux/compiler.h>

#include <linux/linkage.h>

#include <asm/ptrace.h>

#include <asm-generic/error-injection.h>



asmlinkage void just_return_func(void);

void override_function_with_return(struct pt_regs *regs);



#endif /* _ASM_ERROR_INJECTION_H */

arch/x86/kernel/kprobes/core.c

+0 −14
Original line number Diff line number Diff line
@@ -1183,17 +1183,3 @@ int arch_trampoline_kprobe(struct kprobe *p) 
{

	return 0;

}
 


asmlinkage void override_func(void);

asm(

	".type override_func, @function\n"

	"override_func:\n"

	"	ret\n"

	".size override_func, .-override_func\n"

);



void arch_kprobe_override_function(struct pt_regs *regs)

{

	regs->ip = (unsigned long)&override_func;

}

NOKPROBE_SYMBOL(arch_kprobe_override_function);

arch/x86/lib/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ lib-y += memcpy_$(BITS).o 
lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o

lib-$(CONFIG_INSTRUCTION_DECODER) += insn.o inat.o insn-eval.o

lib-$(CONFIG_RANDOMIZE_BASE) += kaslr.o

lib-$(CONFIG_FUNCTION_ERROR_INJECTION)	+= error-inject.o



obj-y += msr.o msr-reg.o msr-reg-export.o hweight.o

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