linux-stable/lib/nlattr.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
// 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 validate_nla(const struct nlattr *nla, int maxtype,
const struct nla_policy *policy,
const char **error_msg)
{
const struct nla_policy *pt;
int minlen = 0, attrlen = nla_len(nla), type = nla_type(nla);
if (type <= 0 || type > maxtype)
return 0;
pt = &policy[type];
BUG_ON(pt->type > NLA_TYPE_MAX);
if ((nla_attr_len[pt->type] && attrlen != nla_attr_len[pt->type]) ||
(pt->type == NLA_EXACT_LEN_WARN && attrlen != pt->len)) {
pr_warn_ratelimited("netlink: '%s': attribute type %d has an invalid length.\n",
current->comm, type);
}
switch (pt->type) {
case NLA_EXACT_LEN:
if (attrlen != pt->len)
return -ERANGE;
break;
case NLA_REJECT:
if (pt->validation_data && error_msg)
*error_msg = pt->validation_data;
return -EINVAL;
case NLA_FLAG:
if (attrlen > 0)
return -ERANGE;
break;
case NLA_BITFIELD32:
if (attrlen != sizeof(struct nla_bitfield32))
return -ERANGE;
return validate_nla_bitfield32(nla, pt->validation_data);
case NLA_NUL_STRING:
if (pt->len)
minlen = min_t(int, attrlen, pt->len + 1);
else
minlen = attrlen;
if (!minlen || memchr(nla_data(nla), '\0', minlen) == NULL)
return -EINVAL;
/* fall through */
case NLA_STRING:
if (attrlen < 1)
return -ERANGE;
if (pt->len) {
char *buf = nla_data(nla);
if (buf[attrlen - 1] == '\0')
attrlen--;
if (attrlen > pt->len)
return -ERANGE;
}
break;
case NLA_BINARY:
if (pt->len && attrlen > pt->len)
return -ERANGE;
break;
case NLA_NESTED:
/* a nested attributes is allowed to be empty; if its not,
* it must have a size of at least NLA_HDRLEN.
*/
if (attrlen == 0)
break;
default:
if (pt->len)
minlen = pt->len;
else if (pt->type != NLA_UNSPEC)
minlen = nla_attr_minlen[pt->type];
if (attrlen < minlen)
return -ERANGE;
}
return 0;
}
/**
* nla_validate - Validate a stream of attributes
* @head: head of attribute stream
* @len: length of attribute stream
* @maxtype: maximum attribute type to be expected
* @policy: validation policy
* @extack: extended ACK report struct
*
* Validates all attributes in the specified attribute stream against the
* specified policy. Attributes with a type exceeding maxtype will be
* ignored. See documenation of struct nla_policy for more details.
*
* Returns 0 on success or a negative error code.
*/
int nla_validate(const struct nlattr *head, int len, int maxtype,
const struct nla_policy *policy,
struct netlink_ext_ack *extack)
{
const struct nlattr *nla;
int rem;
nla_for_each_attr(nla, head, len, rem) {
int err = validate_nla(nla, maxtype, policy, NULL);
if (err < 0) {
NL_SET_BAD_ATTR(extack, nla);
return err;
}
}
return 0;
}
EXPORT_SYMBOL(nla_validate);
/**
* nla_policy_len - Determin the max. length of a policy
* @policy: policy to use
* @n: number of policies
*
* Determines the max. length of the policy. It is currently used
* to allocated Netlink buffers roughly the size of the actual
* message.
*
* Returns 0 on success or a negative error code.
*/
int
nla_policy_len(const struct nla_policy *p, int n)
{
int i, len = 0;
for (i = 0; i < n; i++, p++) {
if (p->len)
len += nla_total_size(p->len);
else if (nla_attr_len[p->type])
len += nla_total_size(nla_attr_len[p->type]);
else if (nla_attr_minlen[p->type])
len += nla_total_size(nla_attr_minlen[p->type]);
}
return len;
}
EXPORT_SYMBOL(nla_policy_len);
/**
* nla_parse - Parse a stream of attributes into a tb buffer
* @tb: destination array with maxtype+1 elements
* @maxtype: maximum attribute type to be expected
* @head: head of attribute stream
* @len: length of attribute stream
* @policy: validation policy
*
* Parses a stream of attributes and stores a pointer to each attribute in
* the tb array accessible via the attribute type. Attributes with a type
* exceeding maxtype will be silently ignored for backwards compatibility
* reasons. policy may be set to NULL if no validation is required.
*
* Returns 0 on success or a negative error code.
*/
int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head,
int len, const struct nla_policy *policy,
struct netlink_ext_ack *extack)
{
const struct nlattr *nla;
int rem, err;
memset(tb, 0, sizeof(struct nlattr *) * (maxtype + 1));
nla_for_each_attr(nla, head, len, rem) {
u16 type = nla_type(nla);
if (type > 0 && type <= maxtype) {
static const char _msg[] = "Attribute failed policy validation";
const char *msg = _msg;
if (policy) {
err = validate_nla(nla, maxtype, policy, &msg);
if (err < 0) {
NL_SET_BAD_ATTR(extack, nla);
if (extack)
extack->_msg = msg;
goto errout;
}
}
tb[type] = (struct nlattr *)nla;
}
}
if (unlikely(rem > 0))
pr_warn_ratelimited("netlink: %d bytes leftover after parsing attributes in process `%s'.\n",
rem, current->comm);
err = 0;
errout:
return err;
}
EXPORT_SYMBOL(nla_parse);
/**
* nla_find - Find a specific attribute in a stream of attributes
* @head: head of attribute stream
* @len: length of attribute stream
* @attrtype: type of attribute to look for
*
* Returns the first attribute in the stream matching the specified type.
*/
struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype)
{
const struct nlattr *nla;
int rem;
nla_for_each_attr(nla, head, len, rem)
if (nla_type(nla) == attrtype)
return (struct nlattr *)nla;
return NULL;
}
EXPORT_SYMBOL(nla_find);
/**
* nla_strlcpy - Copy string attribute payload into a sized buffer
* @dst: where to copy the string to
* @nla: attribute to copy the string from
* @dstsize: size of destination buffer
*
* Copies at most dstsize - 1 bytes into the destination buffer.
* The result is always a valid NUL-terminated string. Unlike
* strlcpy the destination buffer is always padded out.
*
* Returns the length of the source buffer.
*/
size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize)
{
size_t srclen = nla_len(nla);
char *src = nla_data(nla);
if (srclen > 0 && src[srclen - 1] == '\0')
srclen--;
if (dstsize > 0) {
size_t len = (srclen >= dstsize) ? dstsize - 1 : srclen;
memset(dst, 0, dstsize);
memcpy(dst, src, len);
}
return srclen;
}
EXPORT_SYMBOL(nla_strlcpy);
/**
* nla_strdup - Copy string attribute payload into a newly allocated buffer
* @nla: attribute to copy the string from
* @flags: the type of memory to allocate (see kmalloc).
*
* Returns a pointer to the allocated buffer or NULL on error.
*/
char *nla_strdup(const struct nlattr *nla, gfp_t flags)
{
size_t srclen = nla_len(nla);
char *src = nla_data(nla), *dst;
if (srclen > 0 && src[srclen - 1] == '\0')
srclen--;
dst = kmalloc(srclen + 1, flags);
if (dst != NULL) {
memcpy(dst, src, srclen);
dst[srclen] = '\0';
}
return dst;
}
EXPORT_SYMBOL(nla_strdup);
/**
* nla_memcpy - Copy a netlink attribute into another memory area
* @dest: where to copy to memcpy
* @src: netlink attribute to copy from
* @count: size of the destination area
*
* Note: The number of bytes copied is limited by the length of
* attribute's payload. memcpy
*
* Returns the number of bytes copied.
*/
int nla_memcpy(void *dest, const struct nlattr *src, int count)
{
int minlen = min_t(int, count, nla_len(src));
memcpy(dest, nla_data(src), minlen);
if (count > minlen)
memset(dest + minlen, 0, count - minlen);
return minlen;
}
EXPORT_SYMBOL(nla_memcpy);
/**
* nla_memcmp - Compare an attribute with sized memory area
* @nla: netlink attribute
* @data: memory area
* @size: size of memory area
*/
int nla_memcmp(const struct nlattr *nla, const void *data,
size_t size)
{
int d = nla_len(nla) - size;
if (d == 0)
d = memcmp(nla_data(nla), data, size);
return d;
}
EXPORT_SYMBOL(nla_memcmp);
/**
* nla_strcmp - Compare a string attribute against a string
* @nla: netlink string attribute
* @str: another string
*/
int nla_strcmp(const struct nlattr *nla, const char *str)
{
int len = strlen(str);
char *buf = nla_data(nla);
int attrlen = nla_len(nla);
int d;
if (attrlen > 0 && buf[attrlen - 1] == '\0')
attrlen--;
d = attrlen - len;
if (d == 0)
d = memcmp(nla_data(nla), str, len);
return d;
}
EXPORT_SYMBOL(nla_strcmp);
#ifdef CONFIG_NET
/**
* __nla_reserve - reserve room for attribute on the skb
* @skb: socket buffer to reserve room on
* @attrtype: attribute type
* @attrlen: length of attribute payload
*
* Adds a netlink attribute header to a socket buffer and reserves
* room for the payload but does not copy it.
*
* The caller is responsible to ensure that the skb provides enough
* tailroom for the attribute header and payload.
*/
struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen)
{
struct nlattr *nla;
nla = skb_put(skb, nla_total_size(attrlen));
nla->nla_type = attrtype;
nla->nla_len = nla_attr_size(attrlen);
memset((unsigned char *) nla + nla->nla_len, 0, nla_padlen(attrlen));
return nla;
}
EXPORT_SYMBOL(__nla_reserve);
/**
* __nla_reserve_64bit - reserve room for attribute on the skb and align it
* @skb: socket buffer to reserve room on
* @attrtype: attribute type
* @attrlen: length of attribute payload
* @padattr: attribute type for the padding
*
* Adds a netlink attribute header to a socket buffer and reserves
* room for the payload but does not copy it. It also ensure that this
* attribute will have a 64-bit aligned nla_data() area.
*
* The caller is responsible to ensure that the skb provides enough
* tailroom for the attribute header and payload.
*/
struct nlattr *__nla_reserve_64bit(struct sk_buff *skb, int attrtype,
int attrlen, int padattr)
{
if (nla_need_padding_for_64bit(skb))
nla_align_64bit(skb, padattr);
return __nla_reserve(skb, attrtype, attrlen);
}
EXPORT_SYMBOL(__nla_reserve_64bit);
/**
* __nla_reserve_nohdr - reserve room for attribute without header
* @skb: socket buffer to reserve room on
* @attrlen: length of attribute payload
*
* Reserves room for attribute payload without a header.
*
* The caller is responsible to ensure that the skb provides enough
* tailroom for the payload.
*/
void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen)
{
return skb_put_zero(skb, NLA_ALIGN(attrlen));
}
EXPORT_SYMBOL(__nla_reserve_nohdr);
/**
* nla_reserve - reserve room for attribute on the skb
* @skb: socket buffer to reserve room on
* @attrtype: attribute type
* @attrlen: length of attribute payload
*
* Adds a netlink attribute header to a socket buffer and reserves
* room for the payload but does not copy it.
*
* Returns NULL if the tailroom of the skb is insufficient to store
* the attribute header and payload.
*/
struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen)
{
if (unlikely(skb_tailroom(skb) < nla_total_size(attrlen)))
return NULL;
return __nla_reserve(skb, attrtype, attrlen);
}
EXPORT_SYMBOL(nla_reserve);
/**
* nla_reserve_64bit - reserve room for attribute on the skb and align it
* @skb: socket buffer to reserve room on
* @attrtype: attribute type
* @attrlen: length of attribute payload
* @padattr: attribute type for the padding
*
* Adds a netlink attribute header to a socket buffer and reserves
* room for the payload but does not copy it. It also ensure that this
* attribute will have a 64-bit aligned nla_data() area.
*
* Returns NULL if the tailroom of the skb is insufficient to store
* the attribute header and payload.
*/
struct nlattr *nla_reserve_64bit(struct sk_buff *skb, int attrtype, int attrlen,
int padattr)
{
size_t len;
if (nla_need_padding_for_64bit(skb))
len = nla_total_size_64bit(attrlen);
else
len = nla_total_size(attrlen);
if (unlikely(skb_tailroom(skb) < len))
return NULL;
return __nla_reserve_64bit(skb, attrtype, attrlen, padattr);
}
EXPORT_SYMBOL(nla_reserve_64bit);
/**
* nla_reserve_nohdr - reserve room for attribute without header
* @skb: socket buffer to reserve room on
* @attrlen: length of attribute payload
*
* Reserves room for attribute payload without a header.
*
* Returns NULL if the tailroom of the skb is insufficient to store
* the attribute payload.
*/
void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen)
{
if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
return NULL;
return __nla_reserve_nohdr(skb, attrlen);
}
EXPORT_SYMBOL(nla_reserve_nohdr);
/**
* __nla_put - Add a netlink attribute to a socket buffer
* @skb: socket buffer to add attribute to
* @attrtype: attribute type
* @attrlen: length of attribute payload
* @data: head of attribute payload
*
* The caller is responsible to ensure that the skb provides enough
* tailroom for the attribute header and payload.
*/
void __nla_put(struct sk_buff *skb, int attrtype, int attrlen,
const void *data)
{
struct nlattr *nla;
nla = __nla_reserve(skb, attrtype, attrlen);
memcpy(nla_data(nla), data, attrlen);
}
EXPORT_SYMBOL(__nla_put);
/**
* __nla_put_64bit - Add a netlink attribute to a socket buffer and align it
* @skb: socket buffer to add attribute to
* @attrtype: attribute type
* @attrlen: length of attribute payload
* @data: head of attribute payload
* @padattr: attribute type for the padding
*
* The caller is responsible to ensure that the skb provides enough
* tailroom for the attribute header and payload.
*/
void __nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen,
const void *data, int padattr)
{
struct nlattr *nla;
nla = __nla_reserve_64bit(skb, attrtype, attrlen, padattr);
memcpy(nla_data(nla), data, attrlen);
}
EXPORT_SYMBOL(__nla_put_64bit);
/**
* __nla_put_nohdr - Add a netlink attribute without header
* @skb: socket buffer to add attribute to
* @attrlen: length of attribute payload
* @data: head of attribute payload
*
* The caller is responsible to ensure that the skb provides enough
* tailroom for the attribute payload.
*/
void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data)
{
void *start;
start = __nla_reserve_nohdr(skb, attrlen);
memcpy(start, data, attrlen);
}
EXPORT_SYMBOL(__nla_put_nohdr);
/**
* nla_put - Add a netlink attribute to a socket buffer
* @skb: socket buffer to add attribute to
* @attrtype: attribute type
* @attrlen: length of attribute payload
* @data: head of attribute payload
*
* Returns -EMSGSIZE if the tailroom of the skb is insufficient to store
* the attribute header and payload.
*/
int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
{
if (unlikely(skb_tailroom(skb) < nla_total_size(attrlen)))
return -EMSGSIZE;
__nla_put(skb, attrtype, attrlen, data);
return 0;
}
EXPORT_SYMBOL(nla_put);
/**
* nla_put_64bit - Add a netlink attribute to a socket buffer and align it
* @skb: socket buffer to add attribute to
* @attrtype: attribute type
* @attrlen: length of attribute payload
* @data: head of attribute payload
* @padattr: attribute type for the padding
*
* Returns -EMSGSIZE if the tailroom of the skb is insufficient to store
* the attribute header and payload.
*/
int nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen,
const void *data, int padattr)
{
size_t len;
if (nla_need_padding_for_64bit(skb))
len = nla_total_size_64bit(attrlen);
else
len = nla_total_size(attrlen);
if (unlikely(skb_tailroom(skb) < len))
return -EMSGSIZE;
__nla_put_64bit(skb, attrtype, attrlen, data, padattr);
return 0;
}
EXPORT_SYMBOL(nla_put_64bit);
/**
* nla_put_nohdr - Add a netlink attribute without header
* @skb: socket buffer to add attribute to
* @attrlen: length of attribute payload
* @data: head of attribute payload
*
* Returns -EMSGSIZE if the tailroom of the skb is insufficient to store
* the attribute payload.
*/
int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data)
{
if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
return -EMSGSIZE;
__nla_put_nohdr(skb, attrlen, data);
return 0;
}
EXPORT_SYMBOL(nla_put_nohdr);
/**
* nla_append - Add a netlink attribute without header or padding
* @skb: socket buffer to add attribute to
* @attrlen: length of attribute payload
* @data: head of attribute payload
*
* Returns -EMSGSIZE if the tailroom of the skb is insufficient to store
* the attribute payload.
*/
int nla_append(struct sk_buff *skb, int attrlen, const void *data)
{
if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
return -EMSGSIZE;
skb_put_data(skb, data, attrlen);
return 0;
}
EXPORT_SYMBOL(nla_append);
#endif