From 0a833c29d89656025443cb9f0ebff7052dd95ce0 Mon Sep 17 00:00:00 2001 From: Michal Kubecek Date: Wed, 15 Nov 2017 13:09:32 +0100 Subject: genetlink: fix genlmsg_nlhdr() According to the description, first argument of genlmsg_nlhdr() points to what genlmsg_put() returns, i.e. beginning of user header. Therefore we should only subtract size of genetlink header and netlink message header, not user header. This also means we don't need to pass the pointer to genetlink family and the same is true for genl_dump_check_consistent() which is the only caller of genlmsg_nlhdr(). (Note that at the moment, these functions are only used for families which do not have user header so that they are not affected.) Fixes: 670dc2833d14 ("netlink: advertise incomplete dumps") Signed-off-by: Michal Kubecek Reviewed-by: Johannes Berg Signed-off-by: David S. Miller --- include/net/genetlink.h | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) (limited to 'include') diff --git a/include/net/genetlink.h b/include/net/genetlink.h index 5ac169a735f4..decf6012a401 100644 --- a/include/net/genetlink.h +++ b/include/net/genetlink.h @@ -154,15 +154,12 @@ void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, /** * genlmsg_nlhdr - Obtain netlink header from user specified header * @user_hdr: user header as returned from genlmsg_put() - * @family: generic netlink family * * Returns pointer to netlink header. */ -static inline struct nlmsghdr * -genlmsg_nlhdr(void *user_hdr, const struct genl_family *family) +static inline struct nlmsghdr *genlmsg_nlhdr(void *user_hdr) { return (struct nlmsghdr *)((char *)user_hdr - - family->hdrsize - GENL_HDRLEN - NLMSG_HDRLEN); } @@ -190,16 +187,14 @@ static inline int genlmsg_parse(const struct nlmsghdr *nlh, * genl_dump_check_consistent - check if sequence is consistent and advertise if not * @cb: netlink callback structure that stores the sequence number * @user_hdr: user header as returned from genlmsg_put() - * @family: generic netlink family * * Cf. nl_dump_check_consistent(), this just provides a wrapper to make it * simpler to use with generic netlink. */ static inline void genl_dump_check_consistent(struct netlink_callback *cb, - void *user_hdr, - const struct genl_family *family) + void *user_hdr) { - nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr, family)); + nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr)); } /** -- cgit v1.2.3-58-ga151