linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * NETLINK      Netlink attributes

 *

 *      Authors:    Thomas Graf <tgraf@suug.ch>

 *              Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>

 */

​

#include <linux/export.h>

#include <linux/kernel.h>

#include <linux/errno.h>

#include <linux/jiffies.h>

#include <linux/skbuff.h>

#include <linux/string.h>

#include <linux/types.h>

#include <net/netlink.h>

​

/* For these data types, attribute length should be exactly the given

 * size. However, to maintain compatibility with broken commands, if the

 * attribute length does not match the expected size a warning is emitted

 * to the user that the command is sending invalid data and needs to be fixed.

 */

static const u8 nla_attr_len[NLA_TYPE_MAX+1] = {

    [NLA_U8]    = sizeof(u8),

    [NLA_U16]   = sizeof(u16),

    [NLA_U32]   = sizeof(u32),

    [NLA_U64]   = sizeof(u64),

    [NLA_S8]    = sizeof(s8),

    [NLA_S16]   = sizeof(s16),

    [NLA_S32]   = sizeof(s32),

    [NLA_S64]   = sizeof(s64),

};

​

static const u8 nla_attr_minlen[NLA_TYPE_MAX+1] = {

    [NLA_U8]    = sizeof(u8),

    [NLA_U16]   = sizeof(u16),

    [NLA_U32]   = sizeof(u32),

    [NLA_U64]   = sizeof(u64),

    [NLA_MSECS] = sizeof(u64),

    [NLA_NESTED]    = NLA_HDRLEN,

    [NLA_S8]    = sizeof(s8),

    [NLA_S16]   = sizeof(s16),

    [NLA_S32]   = sizeof(s32),

    [NLA_S64]   = sizeof(s64),

};

​

static int validate_nla_bitfield32(const struct nlattr *nla,

                   const u32 *valid_flags_mask)

{

    const struct nla_bitfield32 *bf = nla_data(nla);

​

    if (!valid_flags_mask)

        return -EINVAL;

​

    /*disallow invalid bit selector */

    if (bf->selector & ~*valid_flags_mask)

        return -EINVAL;

​

    /*disallow invalid bit values */

    if (bf->value & ~*valid_flags_mask)

        return -EINVAL;

​

    /*disallow valid bit values that are not selected*/

    if (bf->value & ~bf->selector)

        return -EINVAL;

​

    return 0;

}

​

static int nla_validate_array(const struct nlattr *head, int len, int maxtype,

                  const struct nla_policy *policy,

                  struct netlink_ext_ack *extack)

{

    const struct nlattr *entry;

    int rem;

​

    nla_for_each_attr(entry, head, len, rem) {

        int ret;

​

        if (nla_len(entry) == 0)

            continue;

​

        if (nla_len(entry) < NLA_HDRLEN) {

            NL_SET_ERR_MSG_ATTR(extack, entry,

                        "Array element too short");

            return -ERANGE;

        }

​

        ret = nla_validate(nla_data(entry), nla_len(entry),

                   maxtype, policy, extack);

        if (ret < 0)

            return ret;