diff options
Diffstat (limited to 'drivers/fwctl/main.c')
| -rw-r--r-- | drivers/fwctl/main.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/drivers/fwctl/main.c b/drivers/fwctl/main.c index 4bba6109712e..bd84c4e5b3b9 100644 --- a/drivers/fwctl/main.c +++ b/drivers/fwctl/main.c @@ -27,8 +27,62 @@ struct fwctl_ucmd { u32 user_size; }; +static int ucmd_respond(struct fwctl_ucmd *ucmd, size_t cmd_len) +{ + if (copy_to_user(ucmd->ubuffer, ucmd->cmd, + min_t(size_t, ucmd->user_size, cmd_len))) + return -EFAULT; + return 0; +} + +static int copy_to_user_zero_pad(void __user *to, const void *from, + size_t from_len, size_t user_len) +{ + size_t copy_len; + + copy_len = min(from_len, user_len); + if (copy_to_user(to, from, copy_len)) + return -EFAULT; + if (copy_len < user_len) { + if (clear_user(to + copy_len, user_len - copy_len)) + return -EFAULT; + } + return 0; +} + +static int fwctl_cmd_info(struct fwctl_ucmd *ucmd) +{ + struct fwctl_device *fwctl = ucmd->uctx->fwctl; + struct fwctl_info *cmd = ucmd->cmd; + size_t driver_info_len = 0; + + if (cmd->flags) + return -EOPNOTSUPP; + + if (!fwctl->ops->info && cmd->device_data_len) { + if (clear_user(u64_to_user_ptr(cmd->out_device_data), + cmd->device_data_len)) + return -EFAULT; + } else if (cmd->device_data_len) { + void *driver_info __free(kfree) = + fwctl->ops->info(ucmd->uctx, &driver_info_len); + if (IS_ERR(driver_info)) + return PTR_ERR(driver_info); + + if (copy_to_user_zero_pad(u64_to_user_ptr(cmd->out_device_data), + driver_info, driver_info_len, + cmd->device_data_len)) + return -EFAULT; + } + + cmd->out_device_type = fwctl->ops->device_type; + cmd->device_data_len = driver_info_len; + return ucmd_respond(ucmd, sizeof(*cmd)); +} + /* On stack memory for the ioctl structs */ union fwctl_ucmd_buffer { + struct fwctl_info info; }; struct fwctl_ioctl_op { @@ -48,6 +102,7 @@ struct fwctl_ioctl_op { .execute = _fn, \ } static const struct fwctl_ioctl_op fwctl_ioctl_ops[] = { + IOCTL_OP(FWCTL_INFO, fwctl_cmd_info, struct fwctl_info, out_device_data), }; static long fwctl_fops_ioctl(struct file *filp, unsigned int cmd, |