leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

mac80211: prevent chanctx overcommit

Browse Source 
Do not allocate more channel contexts than a
driver is capable for currently matching interface
combination.

This allows the ieee80211_vif_reserve_chanctx() to
act as a guard against breaking interface
combinations.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Michal Kazior 2014-04-09 15:29:24 +02:00 committed by Johannes Berg
parent 6fa001bc7e
commit c2b90ad880
1 changed files with 23 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
net/mac80211/chan.c
View File

@ -9,6 +9,25 @@
#include "ieee80211_i.h"
#include "driver-ops.h"
static int ieee80211_num_chanctx(struct ieee80211_local *local)
{
struct ieee80211_chanctx *ctx;
int num = 0;
lockdep_assert_held(&local->chanctx_mtx);
list_for_each_entry(ctx, &local->chanctx_list, list)
num++;
return num;
}
static bool ieee80211_can_create_new_chanctx(struct ieee80211_local *local)
{
lockdep_assert_held(&local->chanctx_mtx);
return ieee80211_num_chanctx(local) < ieee80211_max_num_channels(local);
}
static enum nl80211_chan_width ieee80211_get_sta_bw(struct ieee80211_sta *sta)
{
switch (sta->bandwidth) {
@ -751,13 +770,16 @@ int ieee80211_vif_reserve_chanctx(struct ieee80211_sub_if_data *sdata,
* context, reserve our current context
*/
new_ctx = curr_ctx;
} else {
} else if (ieee80211_can_create_new_chanctx(local)) {
/* create a new context and reserve it */
new_ctx = ieee80211_new_chanctx(local, chandef, mode);
if (IS_ERR(new_ctx)) {
ret = PTR_ERR(new_ctx);
goto out;
}
} else {
ret = -EBUSY;
goto out;
}
}