wifi: mac80211: defragment reconfiguration MLE when parsing

Using the scratch buffer (without advancing it) here in the
mlme.c code seems somewhat wrong, defragment the reconfig
multi-link element already when parsing. This might be a bit
more work in certain cases, but makes the whole thing more
regular.

type=cleanup
ticket=none

Change-Id: I4b736ce4fdc199fa1d6b00d00032f448c873a8b4
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-on: https://gerritwcs.ir.intel.com/c/iwlwifi-stack-dev/+/93719
automatic-review: iil_jenkins iil_jenkins <EC.GER.UNIX.IIL.JENKINS@INTEL.COM>
tested: iil_jenkins iil_jenkins <EC.GER.UNIX.IIL.JENKINS@INTEL.COM>
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
x-iwlwifi-stack-dev: b2b1b2120a4f20cd36d0c89c496cb03df330e297

4 files changed, 28 insertions, 17 deletions

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index a8c5c7a3a4..bd3af80f05 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1745,6 +1745,7 @@ struct ieee802_11_elems {
 	const struct ieee80211_eht_cap_elem *eht_cap;
 	const struct ieee80211_eht_operation *eht_operation;
 	const struct ieee80211_multi_link_elem *ml_basic;
+	const struct ieee80211_multi_link_elem *ml_reconf;
 	const struct ieee80211_bandwidth_indication *bandwidth_indication;
 	const struct ieee80211_ttlm_elem *ttlm[IEEE80211_TTLM_MAX_CNT];
 	const struct ieee80211_bss_load_elem *bss_load;
@@ -1773,6 +1774,7 @@ struct ieee802_11_elems {
 
 	/* mult-link element can be de-fragmented and thus u8 is not sufficient */
 	size_t ml_basic_len;
+	size_t ml_reconf_len;
 
 	/* The basic Multi-Link element in the original elements */
 	const struct element *ml_basic_elem;
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index d9907ea2c9..dd395ace8f 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -5758,33 +5758,20 @@ out:
 static void ieee80211_ml_reconfiguration(struct ieee80211_sub_if_data *sdata,
 					 struct ieee802_11_elems *elems)
 {
-	const struct ieee80211_multi_link_elem *ml;
 	const struct element *sub;
-	ssize_t ml_len;
 	unsigned long removed_links = 0;
 	u16 link_removal_timeout[IEEE80211_MLD_MAX_NUM_LINKS] = {};
 	u8 link_id;
 	u32 delay;
 
-	if (!ieee80211_vif_is_mld(&sdata->vif) || !elems->ml_reconf_elem)
+	if (!ieee80211_vif_is_mld(&sdata->vif) || !elems->ml_reconf)
 		return;
 
-	ml_len = cfg80211_defragment_element(elems->ml_reconf_elem,
-					     elems->ie_start,
-					     elems->total_len,
-					     elems->scratch_pos,
-					     elems->scratch + elems->scratch_len -
-					     elems->scratch_pos,
-					     WLAN_EID_FRAGMENT);
-	if (ml_len < 0)
-		return;
-
-	ml = (const void *)elems->scratch_pos;
-
 	/* Directly parse the sub elements as the common information doesn't
 	 * hold any useful information.
 	 */
-	for_each_mle_subelement(sub, (u8 *)ml, ml_len) {
+	for_each_mle_subelement(sub, (const u8 *)elems->ml_reconf,
+				elems->ml_reconf_len) {
 		struct ieee80211_mle_per_sta_profile *prof = (void *)sub->data;
 		u8 *pos = prof->variable;
 		u16 control;
diff --git a/net/mac80211/parse.c b/net/mac80211/parse.c
index 30907ba610..86f7117607 100644
--- a/net/mac80211/parse.c
+++ b/net/mac80211/parse.c
@@ -838,6 +838,26 @@ static void ieee80211_mle_parse_link(struct ieee802_11_elems *elems,
 	_ieee802_11_parse_elems_full(&sub, elems, non_inherit);
 }
 
+static void
+ieee80211_mle_defrag_reconf(struct ieee802_11_elems *elems)
+{
+	ssize_t ml_len;
+
+	ml_len = cfg80211_defragment_element(elems->ml_reconf_elem,
+					     elems->ie_start,
+					     elems->total_len,
+					     elems->scratch_pos,
+					     elems->scratch +
+					     elems->scratch_len -
+					     elems->scratch_pos,
+					     WLAN_EID_FRAGMENT);
+	if (ml_len < 0)
+		return;
+	elems->ml_reconf = (void *)elems->scratch_pos;
+	elems->ml_reconf_len = ml_len;
+	elems->scratch_pos += ml_len;
+}
+
 struct ieee802_11_elems *
 ieee802_11_parse_elems_full(struct ieee80211_elems_parse_params *params)
 {
@@ -883,6 +903,8 @@ ieee802_11_parse_elems_full(struct ieee80211_elems_parse_params *params)
 
 	ieee80211_mle_parse_link(elems, params);
 
+	ieee80211_mle_defrag_reconf(elems);
+
 	if (elems->tim && !elems->parse_error) {
 		const struct ieee80211_tim_ie *tim_ie = elems->tim;
 
diff --git a/versions b/versions
index 8f5af92d4d..5965db793a 100644
--- a/versions
+++ b/versions
@@ -2,4 +2,4 @@ BACKPORTS_VERSION="(see git)"
 BACKPORTED_KERNEL_VERSION="(see git)"
 BACKPORTED_KERNEL_NAME="iwlwifi"
 BACKPORTS_BUILD_TSTAMP=__DATE__ \" \" __TIME__
-BACKPORTS_GIT_TRACKED="iwlwifi-stack-public:master:11897:e5632b48"
+BACKPORTS_GIT_TRACKED="iwlwifi-stack-public:master:11898:b2b1b212"