On Mon, 18 Feb 2019 19:22:14 +0100 (CET), Michal Kubecek wrote:
> Requests a contents of one or more string sets, i.e. indexed arrays of
> strings; this information is provided by ETHTOOL_GSSET_INFO and
> ETHTOOL_GSTRINGS commands of ioctl interface. There are three types of
> requests:
>
> - no NLM_F_DUMP, no device: get "global" stringsets
> - no NLM_F_DUMP, with device: get string sets related to the device
> - NLM_F_DUMP, no device: get device related string sets for all devices
>
> It's possible to request all string sets of given type or only specific
> sets. With ETHA_STRSET_COUNTS flag, only set sizes (number of strings) are
> returned.
> +GET_STRSET
> +----------
> +
> +Requests contents of a string set as provided by ioctl commands
> +ETHTOOL_GSSET_INFO and ETHTOOL_GSTRINGS. String sets are not user writeable
> so
> +that the corresponding SET_STRSET message is only used in kernel replies.
> +There are two types of string sets: global (independent of a device, e.g.
> +device feature names) and device specific (e.g. device private flags).
> +
> +Request contents:
> +
> + ETHA_STRSET_DEV (nested) device identification
> + ETHA_STRSET_COUNTS (flag) request only string
> counts
> + ETHA_STRSET_STRINGSET (nested) string set to request
> + ETHA_STRINGSET_ID (u32) set id
> +
> +Kernel response contents:
> +
> + ETHA_STRSET_DEV (nested) device identification
> + ETHA_STRSET_STRINGSET (nested) string set to request
Is it common to put the device information outside of the main
attribute nest?
> + ETHA_STRINGSET_ID (u32) set id
> + ETHA_STRINGSET_COUNT (u32) number of strings
> + ETHA_STRINGSET_STRINGS (nested) array of strings
> + ETHA_STRING_INDEX (u32) string
> index
> + ETHA_STRING_VALUE (string) string
> value
> +
> +ETHA_STRSET_DEV, if present, identifies the device to request device specific
> +string sets for. Depending on its presence a and NLM_F_DUMP flag, there are
> +three type of GET_STRSET requests:
> +
> + - no NLM_F_DUMP, no device: get "global" stringsets
> + - no NLM_F_DUMP, with device: get string sets related to the device
> + - NLM_F_DUMP, no device: get device related string sets for all devices
> +
> +If there is no ETHA_STRSET_STRINGSET attribute, all string sets of requested
> +type are returned, otherwise only those specified in the request. Flag
> +ETHA_STRSET_COUNTS tells kernel to only return string counts of the sets, not
> +the actual strings.
> +
> +
> +static int get_strset_id(const struct nlattr *nest, u32 *val,
> + struct genl_info *info)
> +{
> + struct nlattr *tb[ETHA_STRINGSET_MAX + 1];
> + int ret;
> +
> + ret = nla_parse_nested(tb, ETHA_STRINGSET_MAX, nest, stringset_policy,
> + info ? info->extack : NULL);
Would it make sense to use strict parsing everywhere from the start?
You seem to add REJECTS, but won't attributes > max get ignored?
> + if (ret < 0)
> + return ret;
> + if (!tb[ETHA_STRINGSET_ID])
> + return -EINVAL;
> +
> + *val = nla_get_u32(tb[ETHA_STRINGSET_ID]);
> + return 0;
> +}
> +
> +static int parse_strset(struct common_req_info *req_info, struct sk_buff
> *skb,
> + struct genl_info *info, const struct nlmsghdr *nlhdr)
> +{
> + struct strset_data *data =
> + container_of(req_info, struct strset_data, reqinfo_base);
> + struct nlattr *attr;
> + int rem, ret;
> +
> + ret = nlmsg_validate(nlhdr, GENL_HDRLEN, ETHA_STRSET_MAX,
> + get_strset_policy, info ? info->extack : NULL);
> + if (ret < 0)
> + return ret;
