From 129d17e8e8daf50f8aff4941fb4a9cda027ab9cf Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Wed, 29 Mar 2017 13:58:06 +0900 Subject: [PATCH] kprobes/x86: Fix the description of __copy_instruction() Fix the description comment of __copy_instruction() function since it has already been changed to return the length of the copied instruction. Signed-off-by: Masami Hiramatsu Cc: Ananth N Mavinakayanahalli Cc: Andrey Ryabinin Cc: Anil S Keshavamurthy Cc: Borislav Petkov Cc: Brian Gerst Cc: David S . Miller Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Ye Xiaolong Link: http://lkml.kernel.org/r/149076347582.22469.3775133607244923462.stgit@devbox Signed-off-by: Ingo Molnar --- arch/x86/kernel/kprobes/core.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index 9eae5a6c5870..81d4dc786dae 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -350,11 +350,10 @@ static int is_IF_modifier(kprobe_opcode_t *insn) } /* - * Copy an instruction and adjust the displacement if the instruction - * uses the %rip-relative addressing mode. - * If it does, Return the address of the 32-bit displacement word. - * If not, return null. - * Only applicable to 64-bit x86. + * Copy an instruction with recovering modified instruction by kprobes + * and adjust the displacement if the instruction uses the %rip-relative + * addressing mode. + * This returns the length of copied instruction, or 0 if it has an error. */ int __copy_instruction(u8 *dest, u8 *src) { @@ -376,6 +375,7 @@ int __copy_instruction(u8 *dest, u8 *src) memcpy(dest, insn.kaddr, length); #ifdef CONFIG_X86_64 + /* Only x86_64 has RIP relative instructions */ if (insn_rip_relative(&insn)) { s64 newdisp; u8 *disp; -- 2.20.1