Re: [PATCH -tip 4/6 V4] x86: kprobes checks safeness of insertion address.

Ananth N Mavinakayanahalli
2009-04-03T05:19:14Z

On Thu, Apr 02, 2009 at 01:24:57PM -0400, Masami Hiramatsu wrote:

> +/* Recover original instruction */
> +static int recover_probed_instruction(kprobe_opcode_t *buf, unsigned long addr)
> +{
> + struct kprobe *kp;
> + kp = get_kprobe((void *)addr);
> + if (!kp)
> + return -EINVAL;
> +
> + /* Don't use p->ainsn.insn; which will be modified by fix_riprel */
> + memcpy(buf, kp->addr, MAX_INSN_SIZE * sizeof(kprobe_opcode_t));
> + buf[0] = kp->opcode;
> + return 0;
> +}
> +
> +/* Dummy buffers for lookup_symbol_attrs */
> +static char __dummy_buf[KSYM_NAME_LEN];
> +
> +/* Check whether the address can be probed */
> +static int __kprobes can_probe(unsigned long paddr)

A better description would've been "Check if paddr is at an instruction
boundary". Otherwise looks good.

Ananth