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 <mkubecek@suse.cz>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index 2c98152d1e1bf76d247ef8ad0b0c8ae156907cf0..1d025ab9568f216172d6fd1049056b6187ab7c40 100644 (file)
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -2411,7 +2411,7 @@ static int dump_secy(struct macsec_secy *secy, struct net_device *dev,
        if (!hdr)
                return -EMSGSIZE;
 
-       genl_dump_check_consistent(cb, hdr, &macsec_fam);
+       genl_dump_check_consistent(cb, hdr);
 
        if (nla_put_u32(skb, MACSEC_ATTR_IFINDEX, dev->ifindex))
                goto nla_put_failure;

diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c
index 07a49f58070aa061b763c8723bab99d335a9fab7..7c3600643c7fdb540e71696e928acedaee3ccccf 100644 (file)
--- a/drivers/net/wireless/mac80211_hwsim.c
+++ b/drivers/net/wireless/mac80211_hwsim.c
@@ -2805,7 +2805,7 @@ static int mac80211_hwsim_get_radio(struct sk_buff *skb,
                return -EMSGSIZE;
 
        if (cb)
-               genl_dump_check_consistent(cb, hdr, &hwsim_genl_family);
+               genl_dump_check_consistent(cb, hdr);
 
        if (data->alpha2[0] && data->alpha2[1])
                param.reg_alpha2 = data->alpha2;

diff --git a/include/net/genetlink.h b/include/net/genetlink.h
index 5ac169a735f4bdfab76d76f2036488bcf5e0347a..decf6012a40163c564900c3c39e50d2bf48aa64f 100644 (file)
--- 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));
 }
 
 /**

diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c
index f6359c277212518d7725b0b91978500b244f4da8..c0b83dc9d99305850a61b647fe362b6ed52c50aa 100644 (file)
--- a/net/nfc/netlink.c
+++ b/net/nfc/netlink.c
@@ -75,7 +75,7 @@ static int nfc_genl_send_target(struct sk_buff *msg, struct nfc_target *target,
        if (!hdr)
                return -EMSGSIZE;
 
-       genl_dump_check_consistent(cb, hdr, &nfc_genl_family);
+       genl_dump_check_consistent(cb, hdr);
 
        if (nla_put_u32(msg, NFC_ATTR_TARGET_INDEX, target->idx) ||
            nla_put_u32(msg, NFC_ATTR_PROTOCOLS, target->supported_protocols) ||
@@ -603,7 +603,7 @@ static int nfc_genl_send_device(struct sk_buff *msg, struct nfc_dev *dev,
                return -EMSGSIZE;
 
        if (cb)
-               genl_dump_check_consistent(cb, hdr, &nfc_genl_family);
+               genl_dump_check_consistent(cb, hdr);
 
        if (nfc_genl_setup_device_added(dev, msg))
                goto nla_put_failure;
@@ -1356,7 +1356,7 @@ static int nfc_genl_send_se(struct sk_buff *msg, struct nfc_dev *dev,
                        goto nla_put_failure;
 
                if (cb)
-                       genl_dump_check_consistent(cb, hdr, &nfc_genl_family);
+                       genl_dump_check_consistent(cb, hdr);
 
                if (nla_put_u32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx) ||
                    nla_put_u32(msg, NFC_ATTR_SE_INDEX, se->idx) ||

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index bb16f1ec766ead1e65fb6e4196a4278ff09a67a3..a0e1951227fab1297ee8929dddb3a4a911ef2a56 100644 (file)
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -6291,7 +6291,7 @@ static int nl80211_send_regdom(struct sk_buff *msg, struct netlink_callback *cb,
        if (!hdr)
                return -1;
 
-       genl_dump_check_consistent(cb, hdr, &nl80211_fam);
+       genl_dump_check_consistent(cb, hdr);
 
        if (nl80211_put_regdom(regdom, msg))
                goto nla_put_failure;
@@ -7722,7 +7722,7 @@ static int nl80211_send_bss(struct sk_buff *msg, struct netlink_callback *cb,
        if (!hdr)
                return -1;
 
-       genl_dump_check_consistent(cb, hdr, &nl80211_fam);
+       genl_dump_check_consistent(cb, hdr);
 
        if (nla_put_u32(msg, NL80211_ATTR_GENERATION, rdev->bss_generation))
                goto nla_put_failure;