Commit 95d06e92 authored by Breno Leitao's avatar Breno Leitao Committed by Jakub Kicinski
Browse files

netlink: Introduce nlmsg_payload helper 



Create a new helper function, nlmsg_payload(), to simplify checking and
retrieving Netlink message payloads.

This reduces boilerplate code for users who need to verify the message
length before accessing its data.

Suggested-by: default avatarJakub Kicinski <kuba@kernel.org>
Signed-off-by: default avatarBreno Leitao <leitao@debian.org>
Reviewed-by: default avatarJakub Kicinski <kuba@kernel.org>
Reviewed-by: default avatarKuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250414-nlmsg-v2-1-3d90cb42c6af@debian.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 0418711f

include/net/netlink.h

+16 −0
Original line number Diff line number Diff line
@@ -611,6 +611,22 @@ static inline int nlmsg_len(const struct nlmsghdr *nlh) 
	return nlh->nlmsg_len - NLMSG_HDRLEN;

}



/**

 * nlmsg_payload - message payload if the data fits in the len

 * @nlh: netlink message header

 * @len: struct length

 *

 * Returns: The netlink message payload/data if the length is sufficient,

 * otherwise NULL.

 */

static inline void *nlmsg_payload(const struct nlmsghdr *nlh, size_t len)

{

	if (nlh->nlmsg_len < nlmsg_msg_size(len))

		return NULL;



	return nlmsg_data(nlh);

}



/**

 * nlmsg_attrdata - head of attributes data

 * @nlh: netlink message header