cfg80211: Properly track transmitting and non-transmitting BSS

When holding data of the non-transmitting BSS, we need to keep the
transmitting BSS data on. Otherwise it will be released, and release
the non-transmitting BSS with it.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Sara Sharon 2019-01-21 12:22:21 +02:00 committed by Johannes Berg
parent 1c8745f3ec
commit a3584f56de
2 changed files with 46 additions and 2 deletions

View File

@ -153,6 +153,7 @@ struct cfg80211_internal_bss {
struct list_head list;
struct list_head hidden_list;
struct list_head nontrans_list;
struct cfg80211_bss *transmitted_bss;
struct rb_node rbn;
u64 ts_boottime;
unsigned long ts;
@ -183,12 +184,23 @@ static inline struct cfg80211_internal_bss *bss_from_pub(struct cfg80211_bss *pu
static inline void cfg80211_hold_bss(struct cfg80211_internal_bss *bss)
{
atomic_inc(&bss->hold);
if (bss->transmitted_bss) {
bss = container_of(bss->transmitted_bss,
struct cfg80211_internal_bss, pub);
atomic_inc(&bss->hold);
}
}
static inline void cfg80211_unhold_bss(struct cfg80211_internal_bss *bss)
{
int r = atomic_dec_return(&bss->hold);
WARN_ON(r < 0);
if (bss->transmitted_bss) {
bss = container_of(bss->transmitted_bss,
struct cfg80211_internal_bss, pub);
r = atomic_dec_return(&bss->hold);
WARN_ON(r < 0);
}
}

View File

@ -110,6 +110,12 @@ static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
pub);
bss->refcount++;
}
if (bss->transmitted_bss) {
bss = container_of(bss->transmitted_bss,
struct cfg80211_internal_bss,
pub);
bss->refcount++;
}
}
static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
@ -126,6 +132,18 @@ static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
if (hbss->refcount == 0)
bss_free(hbss);
}
if (bss->transmitted_bss) {
struct cfg80211_internal_bss *tbss;
tbss = container_of(bss->transmitted_bss,
struct cfg80211_internal_bss,
pub);
tbss->refcount--;
if (tbss->refcount == 0)
bss_free(tbss);
}
bss->refcount--;
if (bss->refcount == 0)
bss_free(bss);
@ -1024,6 +1042,7 @@ static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
static struct cfg80211_internal_bss *
cfg80211_bss_update(struct cfg80211_registered_device *rdev,
struct cfg80211_internal_bss *tmp,
struct cfg80211_bss *trans_bss,
bool signal_valid)
{
struct cfg80211_internal_bss *found = NULL;
@ -1181,6 +1200,17 @@ cfg80211_bss_update(struct cfg80211_registered_device *rdev,
goto drop;
}
/* This must be before the call to bss_ref_get */
if (trans_bss) {
struct cfg80211_internal_bss *pbss =
container_of(trans_bss,
struct cfg80211_internal_bss,
pub);
new->transmitted_bss = trans_bss;
bss_ref_get(rdev, pbss);
}
list_add_tail(&new->list, &rdev->bss_list);
rdev->bss_entries++;
rb_insert_bss(rdev, new);
@ -1336,7 +1366,8 @@ cfg80211_inform_single_bss_data(struct wiphy *wiphy,
signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
wiphy->max_adj_channel_rssi_comp;
res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, trans_bss,
signal_valid);
if (!res)
return NULL;
@ -1639,7 +1670,8 @@ cfg80211_inform_single_bss_frame_data(struct wiphy *wiphy,
signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
wiphy->max_adj_channel_rssi_comp;
res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, trans_bss,
signal_valid);
if (!res)
return NULL;