diff options
| -rw-r--r-- | arch/x86/kernel/kprobes/core.c | 20 |
1 files changed, 11 insertions, 9 deletions
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index 33390ed4dcf3..fd0420a3e72e 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -655,17 +655,19 @@ static int prepare_emulation(struct kprobe *p, struct insn *insn) * is determined by the MOD/RM byte. */ opcode = insn->modrm.bytes[0]; - if ((opcode & 0x30) == 0x10) { - if ((opcode & 0x8) == 0x8) - return -EOPNOTSUPP; /* far call */ - /* call absolute, indirect */ + switch (X86_MODRM_REG(opcode)) { + case 0b010: /* FF /2, call near, absolute indirect */ p->ainsn.emulate_op = kprobe_emulate_call_indirect; - } else if ((opcode & 0x30) == 0x20) { - if ((opcode & 0x8) == 0x8) - return -EOPNOTSUPP; /* far jmp */ - /* jmp near absolute indirect */ + break; + case 0b100: /* FF /4, jmp near, absolute indirect */ p->ainsn.emulate_op = kprobe_emulate_jmp_indirect; - } else + break; + case 0b011: /* FF /3, call far, absolute indirect */ + case 0b101: /* FF /5, jmp far, absolute indirect */ + return -EOPNOTSUPP; + } + + if (!p->ainsn.emulate_op) break; if (insn->addr_bytes != sizeof(unsigned long)) |