| Date | Sun, 14 Feb 2021 16:30:09 +0000 | From | Al Viro <> | Subject | Re: [PATCH v2 4/8] cxl/mem: Add basic IOCTL interface |
| |
On Tue, Feb 09, 2021 at 04:02:55PM -0800, Ben Widawsky wrote:
> +static int handle_mailbox_cmd_from_user(struct cxl_memdev *cxlmd, > + const struct cxl_mem_command *cmd, > + u64 in_payload, u64 out_payload, > + struct cxl_send_command __user *s) > +{ > + struct cxl_mem *cxlm = cxlmd->cxlm; > + struct device *dev = &cxlmd->dev; > + struct mbox_cmd mbox_cmd = { > + .opcode = cmd->opcode, > + .size_in = cmd->info.size_in, > + }; > + s32 user_size_out; > + int rc; > + > + if (get_user(user_size_out, &s->out.size)) > + return -EFAULT;
You have already copied it in. Never reread stuff from userland - it *can* change under you.
|