diff options
| author | andrea merello <andrea.merello@gmail.com> | 2014-01-20 01:21:49 +0400 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2014-02-05 00:48:13 +0400 |
| commit | 52512072738c851896c8bfa31938eba1e9b9bc62 (patch) | |
| tree | f72b395870a7c268e960178ef58177fea0a26bdb /net/mac80211/main.c | |
| parent | 30ef7ef9672d92ab2cac37f60a31955c118321e7 (diff) | |
| download | linux-52512072738c851896c8bfa31938eba1e9b9bc62.tar.xz | |
mac80211: add check on hw->max_signal value on ieee80211_register_hw
When IEEE80211_HW_SIGNAL_UNSPEC is set, mac80211 will perform a
division by max_signal in ieee80211_bss_info_update. If max_signal
is not properly set by the driver (for example it is zero) this
leads to a divide error and crash.
Thanks to Larry Finger, who pointed me to this.
This patch adds in ieee80211_register_hw one more check to detect
this condition and eventually returns -EINVAL, as already done for
other checks already performed there.
Signed-off-by: andrea merello <andrea.merello@gmail.com>
[move to an already existing SIGNAL_UNSPEC check]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'net/mac80211/main.c')
| -rw-r--r-- | net/mac80211/main.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/net/mac80211/main.c b/net/mac80211/main.c index d767cfb9b45f..1f7d8422d62d 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -893,10 +893,15 @@ int ieee80211_register_hw(struct ieee80211_hw *hw) /* mac80211 supports control port protocol changing */ local->hw.wiphy->flags |= WIPHY_FLAG_CONTROL_PORT_PROTOCOL; - if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) + if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) { local->hw.wiphy->signal_type = CFG80211_SIGNAL_TYPE_MBM; - else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) + } else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) { local->hw.wiphy->signal_type = CFG80211_SIGNAL_TYPE_UNSPEC; + if (hw->max_signal <= 0) { + result = -EINVAL; + goto fail_wiphy_register; + } + } WARN((local->hw.flags & IEEE80211_HW_SUPPORTS_UAPSD) && (local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK), |