linux/arch/x86/include/asm/kprobes.h

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#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.
*/
kprobes: move kprobe declarations to asm-generic/kprobes.h Often all is needed is these small helpers, instead of compiler.h or a full kprobes.h. This is important for asm helpers, in fact even some asm/kprobes.h make use of these helpers... instead just keep a generic asm file with helpers useful for asm code with the least amount of clutter as possible. Likewise we need now to also address what to do about this file for both when architectures have CONFIG_HAVE_KPROBES, and when they do not. Then for when architectures have CONFIG_HAVE_KPROBES but have disabled CONFIG_KPROBES. Right now most asm/kprobes.h do not have guards against CONFIG_KPROBES, this means most architecture code cannot include asm/kprobes.h safely. Correct this and add guards for architectures missing them. Additionally provide architectures that not have kprobes support with the default asm-generic solution. This lets us force asm/kprobes.h on the header include/linux/kprobes.h always, but most importantly we can now safely include just asm/kprobes.h on architecture code without bringing the full kitchen sink of header files. Two architectures already provided a guard against CONFIG_KPROBES on its kprobes.h: sh, arch. The rest of the architectures needed gaurds added. We avoid including any not-needed headers on asm/kprobes.h unless kprobes have been enabled. In a subsequent atomic change we can try now to remove compiler.h from include/linux/kprobes.h. During this sweep I've also identified a few architectures defining a common macro needed for both kprobes and ftrace, that of the definition of the breakput instruction up. Some refer to this as BREAKPOINT_INSTRUCTION. This must be kept outside of the #ifdef CONFIG_KPROBES guard. [mcgrof@kernel.org: fix arm64 build] Link: http://lkml.kernel.org/r/CAB=NE6X1WMByuARS4mZ1g9+W=LuVBnMDnh_5zyN0CLADaVh=Jw@mail.gmail.com [sfr@canb.auug.org.au: fixup for kprobes declarations moving] Link: http://lkml.kernel.org/r/20170214165933.13ebd4f4@canb.auug.org.au Link: http://lkml.kernel.org/r/20170203233139.32682-1-mcgrof@kernel.org Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-27 22:26:56 +00:00
#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
kprobes/x86: Support kprobes jump optimization on x86 Introduce x86 arch-specific optimization code, which supports both of x86-32 and x86-64. This code also supports safety checking, which decodes whole of a function in which probe is inserted, and checks following conditions before optimization: - The optimized instructions which will be replaced by a jump instruction don't straddle the function boundary. - There is no indirect jump instruction, because it will jumps into the address range which is replaced by jump operand. - There is no jump/loop instruction which jumps into the address range which is replaced by jump operand. - Don't optimize kprobes if it is in functions into which fixup code will jumps. This uses text_poke_multibyte() which doesn't support modifying code on NMI/MCE handler. However, since kprobes itself doesn't support NMI/MCE code probing, it's not a problem. Changes in v9: - Use *_text_reserved() for checking the probe can be optimized. - Verify jump address range is in 2G range when preparing slot. - Backup original code when switching optimized buffer, instead of preparing buffer, because there can be int3 of other probes in preparing phase. - Check kprobe is disabled in arch_check_optimized_kprobe(). - Strictly check indirect jump opcodes (ff /4, ff /5). Changes in v6: - Split stop_machine-based jump patching code. - Update comments and coding style. Changes in v5: - Introduce stop_machine-based jump replacing. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Anders Kaseorg <andersk@ksplice.com> Cc: Tim Abbott <tabbott@ksplice.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Jason Baron <jbaron@redhat.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> LKML-Reference: <20100225133446.6725.78994.stgit@localhost6.localdomain6> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-25 13:34:46 +00:00
#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)
kprobes/x86: Support kprobes jump optimization on x86 Introduce x86 arch-specific optimization code, which supports both of x86-32 and x86-64. This code also supports safety checking, which decodes whole of a function in which probe is inserted, and checks following conditions before optimization: - The optimized instructions which will be replaced by a jump instruction don't straddle the function boundary. - There is no indirect jump instruction, because it will jumps into the address range which is replaced by jump operand. - There is no jump/loop instruction which jumps into the address range which is replaced by jump operand. - Don't optimize kprobes if it is in functions into which fixup code will jumps. This uses text_poke_multibyte() which doesn't support modifying code on NMI/MCE handler. However, since kprobes itself doesn't support NMI/MCE code probing, it's not a problem. Changes in v9: - Use *_text_reserved() for checking the probe can be optimized. - Verify jump address range is in 2G range when preparing slot. - Backup original code when switching optimized buffer, instead of preparing buffer, because there can be int3 of other probes in preparing phase. - Check kprobe is disabled in arch_check_optimized_kprobe(). - Strictly check indirect jump opcodes (ff /4, ff /5). Changes in v6: - Split stop_machine-based jump patching code. - Update comments and coding style. Changes in v5: - Introduce stop_machine-based jump replacing. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Anders Kaseorg <andersk@ksplice.com> Cc: Tim Abbott <tabbott@ksplice.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Jason Baron <jbaron@redhat.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> LKML-Reference: <20100225133446.6725.78994.stgit@localhost6.localdomain6> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-25 13:34:46 +00:00
/* 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[];
kprobes/x86: Support kprobes jump optimization on x86 Introduce x86 arch-specific optimization code, which supports both of x86-32 and x86-64. This code also supports safety checking, which decodes whole of a function in which probe is inserted, and checks following conditions before optimization: - The optimized instructions which will be replaced by a jump instruction don't straddle the function boundary. - There is no indirect jump instruction, because it will jumps into the address range which is replaced by jump operand. - There is no jump/loop instruction which jumps into the address range which is replaced by jump operand. - Don't optimize kprobes if it is in functions into which fixup code will jumps. This uses text_poke_multibyte() which doesn't support modifying code on NMI/MCE handler. However, since kprobes itself doesn't support NMI/MCE code probing, it's not a problem. Changes in v9: - Use *_text_reserved() for checking the probe can be optimized. - Verify jump address range is in 2G range when preparing slot. - Backup original code when switching optimized buffer, instead of preparing buffer, because there can be int3 of other probes in preparing phase. - Check kprobe is disabled in arch_check_optimized_kprobe(). - Strictly check indirect jump opcodes (ff /4, ff /5). Changes in v6: - Split stop_machine-based jump patching code. - Update comments and coding style. Changes in v5: - Introduce stop_machine-based jump replacing. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Anders Kaseorg <andersk@ksplice.com> Cc: Tim Abbott <tabbott@ksplice.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Jason Baron <jbaron@redhat.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> LKML-Reference: <20100225133446.6725.78994.stgit@localhost6.localdomain6> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-25 13:34:46 +00:00
#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);
/* 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;
};
kprobes/x86: Support kprobes jump optimization on x86 Introduce x86 arch-specific optimization code, which supports both of x86-32 and x86-64. This code also supports safety checking, which decodes whole of a function in which probe is inserted, and checks following conditions before optimization: - The optimized instructions which will be replaced by a jump instruction don't straddle the function boundary. - There is no indirect jump instruction, because it will jumps into the address range which is replaced by jump operand. - There is no jump/loop instruction which jumps into the address range which is replaced by jump operand. - Don't optimize kprobes if it is in functions into which fixup code will jumps. This uses text_poke_multibyte() which doesn't support modifying code on NMI/MCE handler. However, since kprobes itself doesn't support NMI/MCE code probing, it's not a problem. Changes in v9: - Use *_text_reserved() for checking the probe can be optimized. - Verify jump address range is in 2G range when preparing slot. - Backup original code when switching optimized buffer, instead of preparing buffer, because there can be int3 of other probes in preparing phase. - Check kprobe is disabled in arch_check_optimized_kprobe(). - Strictly check indirect jump opcodes (ff /4, ff /5). Changes in v6: - Split stop_machine-based jump patching code. - Update comments and coding style. Changes in v5: - Introduce stop_machine-based jump replacing. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Anders Kaseorg <andersk@ksplice.com> Cc: Tim Abbott <tabbott@ksplice.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Jason Baron <jbaron@redhat.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> LKML-Reference: <20100225133446.6725.78994.stgit@localhost6.localdomain6> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-25 13:34:46 +00:00
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);
kprobes: move kprobe declarations to asm-generic/kprobes.h Often all is needed is these small helpers, instead of compiler.h or a full kprobes.h. This is important for asm helpers, in fact even some asm/kprobes.h make use of these helpers... instead just keep a generic asm file with helpers useful for asm code with the least amount of clutter as possible. Likewise we need now to also address what to do about this file for both when architectures have CONFIG_HAVE_KPROBES, and when they do not. Then for when architectures have CONFIG_HAVE_KPROBES but have disabled CONFIG_KPROBES. Right now most asm/kprobes.h do not have guards against CONFIG_KPROBES, this means most architecture code cannot include asm/kprobes.h safely. Correct this and add guards for architectures missing them. Additionally provide architectures that not have kprobes support with the default asm-generic solution. This lets us force asm/kprobes.h on the header include/linux/kprobes.h always, but most importantly we can now safely include just asm/kprobes.h on architecture code without bringing the full kitchen sink of header files. Two architectures already provided a guard against CONFIG_KPROBES on its kprobes.h: sh, arch. The rest of the architectures needed gaurds added. We avoid including any not-needed headers on asm/kprobes.h unless kprobes have been enabled. In a subsequent atomic change we can try now to remove compiler.h from include/linux/kprobes.h. During this sweep I've also identified a few architectures defining a common macro needed for both kprobes and ftrace, that of the definition of the breakput instruction up. Some refer to this as BREAKPOINT_INSTRUCTION. This must be kept outside of the #ifdef CONFIG_KPROBES guard. [mcgrof@kernel.org: fix arm64 build] Link: http://lkml.kernel.org/r/CAB=NE6X1WMByuARS4mZ1g9+W=LuVBnMDnh_5zyN0CLADaVh=Jw@mail.gmail.com [sfr@canb.auug.org.au: fixup for kprobes declarations moving] Link: http://lkml.kernel.org/r/20170214165933.13ebd4f4@canb.auug.org.au Link: http://lkml.kernel.org/r/20170203233139.32682-1-mcgrof@kernel.org Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-27 22:26:56 +00:00
#endif /* CONFIG_KPROBES */
#endif /* _ASM_X86_KPROBES_H */