From ff261964cfcfe49d73690ca29b0ba2853d9497e3 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Sat, 19 Apr 2014 14:15:27 +0200 Subject: [PATCH] uprobes/x86: Shift "insn_complete" from branch_setup_xol_ops() to uprobe_init_insn() Change uprobe_init_insn() to make insn_complete() == T, this makes other insn_get_*() calls unnecessary. Signed-off-by: Oleg Nesterov Reviewed-by: Jim Keniston Acked-by: Srikar Dronamraju --- arch/x86/kernel/uprobes.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c index b3b25ddc04fb..98d7db50f425 100644 --- a/arch/x86/kernel/uprobes.c +++ b/arch/x86/kernel/uprobes.c @@ -209,8 +209,11 @@ static int uprobe_init_insn(struct arch_uprobe *auprobe, struct insn *insn, bool u32 volatile *good_insns; insn_init(insn, auprobe->insn, x86_64); + /* has the side-effect of processing the entire instruction */ + insn_get_length(insn); + if (WARN_ON_ONCE(!insn_complete(insn))) + return -ENOEXEC; - insn_get_opcode(insn); if (is_prefix_bad(insn)) return -ENOTSUPP; @@ -283,8 +286,6 @@ handle_riprel_insn(struct arch_uprobe *auprobe, struct insn *insn) * is the immediate operand. */ cursor = auprobe->insn + insn_offset_modrm(insn); - insn_get_length(insn); - /* * Convert from rip-relative addressing to indirect addressing * via a scratch register. Change the r/m field from 0x5 (%rip) @@ -564,11 +565,6 @@ static int branch_setup_xol_ops(struct arch_uprobe *auprobe, struct insn *insn) u8 opc1 = OPCODE1(insn); int i; - /* has the side-effect of processing the entire instruction */ - insn_get_length(insn); - if (WARN_ON_ONCE(!insn_complete(insn))) - return -ENOEXEC; - switch (opc1) { case 0xeb: /* jmp 8 */ case 0xe9: /* jmp 32 */ @@ -654,7 +650,6 @@ int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, fix_ip = false; break; case 0xff: - insn_get_modrm(&insn); switch (MODRM_REG(&insn)) { case 2: case 3: /* call or lcall, indirect */ fix_call = true;