From 05cb91085760ca378f28fc274fbf77fc4fd9886c Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 28 Oct 2011 11:59:47 +0200 Subject: [PATCH] mac80211: disable powersave for broken APs Only AID values 1-2007 are valid, but some APs have been found to send random bogus values, in the reported case an AP that was sending the AID field value 0xffff, an AID of 0x3fff (16383). There isn't much we can do but disable powersave since there's no way it can work properly in this case. Cc: stable@vger.kernel.org Reported-by: Bill C Riemers Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/mac80211/ieee80211_i.h | 1 + net/mac80211/mlme.c | 18 ++++++++++++++++-- 2 files changed, 17 insertions(+), 2 deletions(-) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 4c3d1f591bec..ea10a51babda 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -389,6 +389,7 @@ struct ieee80211_if_managed { unsigned long timers_running; /* used for quiesce/restart */ bool powersave; /* powersave requested for this iface */ + bool broken_ap; /* AP is broken -- turn off powersave */ enum ieee80211_smps_mode req_smps, /* requested smps mode */ ap_smps, /* smps mode AP thinks we're in */ driver_smps_mode; /* smps mode request */ diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index ba2da11a997b..17258feaab9b 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -637,6 +637,9 @@ static bool ieee80211_powersave_allowed(struct ieee80211_sub_if_data *sdata) if (!mgd->powersave) return false; + if (mgd->broken_ap) + return false; + if (!mgd->associated) return false; @@ -1489,10 +1492,21 @@ static bool ieee80211_assoc_success(struct ieee80211_work *wk, capab_info = le16_to_cpu(mgmt->u.assoc_resp.capab_info); if ((aid & (BIT(15) | BIT(14))) != (BIT(15) | BIT(14))) - printk(KERN_DEBUG "%s: invalid aid value %d; bits 15:14 not " - "set\n", sdata->name, aid); + printk(KERN_DEBUG + "%s: invalid AID value 0x%x; bits 15:14 not set\n", + sdata->name, aid); aid &= ~(BIT(15) | BIT(14)); + ifmgd->broken_ap = false; + + if (aid == 0 || aid > IEEE80211_MAX_AID) { + printk(KERN_DEBUG + "%s: invalid AID value %d (out of range), turn off PS\n", + sdata->name, aid); + aid = 0; + ifmgd->broken_ap = true; + } + pos = mgmt->u.assoc_resp.variable; ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems); -- GitLab