From a754055a1296fcbe6f32de3a5eaca6efb2fd1865 Mon Sep 17 00:00:00 2001 From: Emmanuel Grumbach Date: Mon, 16 Sep 2013 11:12:07 +0300 Subject: mac80211: correctly close cancelled scans __ieee80211_scan_completed is called from a worker. This means that the following flow is possible. * driver calls ieee80211_scan_completed * mac80211 cancels the scan (that is already complete) * __ieee80211_scan_completed runs When scan_work will finally run, it will see that the scan hasn't been aborted and might even trigger another scan on another band. This leads to a situation where cfg80211's scan is not done and no further scan can be issued. Fix this by setting a new flag when a HW scan is being cancelled so that no other scan will be triggered. Cc: stable@vger.kernel.org Signed-off-by: Emmanuel Grumbach Signed-off-by: Johannes Berg --- net/mac80211/ieee80211_i.h | 3 +++ net/mac80211/scan.c | 19 +++++++++++++++++++ 2 files changed, 22 insertions(+) (limited to 'net') diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index b6186517ec56..611abfcfb5eb 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -893,6 +893,8 @@ struct tpt_led_trigger { * that the scan completed. * @SCAN_ABORTED: Set for our scan work function when the driver reported * a scan complete for an aborted scan. + * @SCAN_HW_CANCELLED: Set for our scan work function when the scan is being + * cancelled. */ enum { SCAN_SW_SCANNING, @@ -900,6 +902,7 @@ enum { SCAN_ONCHANNEL_SCANNING, SCAN_COMPLETED, SCAN_ABORTED, + SCAN_HW_CANCELLED, }; /** diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c index 08afe74b98f4..d2d17a449224 100644 --- a/net/mac80211/scan.c +++ b/net/mac80211/scan.c @@ -238,6 +238,9 @@ static bool ieee80211_prep_hw_scan(struct ieee80211_local *local) enum ieee80211_band band; int i, ielen, n_chans; + if (test_bit(SCAN_HW_CANCELLED, &local->scanning)) + return false; + do { if (local->hw_scan_band == IEEE80211_NUM_BANDS) return false; @@ -940,7 +943,23 @@ void ieee80211_scan_cancel(struct ieee80211_local *local) if (!local->scan_req) goto out; + /* + * We have a scan running and the driver already reported completion, + * but the worker hasn't run yet or is stuck on the mutex - mark it as + * cancelled. + */ + if (test_bit(SCAN_HW_SCANNING, &local->scanning) && + test_bit(SCAN_COMPLETED, &local->scanning)) { + set_bit(SCAN_HW_CANCELLED, &local->scanning); + goto out; + } + if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { + /* + * Make sure that __ieee80211_scan_completed doesn't trigger a + * scan on another band. + */ + set_bit(SCAN_HW_CANCELLED, &local->scanning); if (local->ops->cancel_hw_scan) drv_cancel_hw_scan(local, rcu_dereference_protected(local->scan_sdata, -- cgit v1.2.3-58-ga151 From f38dd58ccca0d612e62509f75e99952dcf316cb2 Mon Sep 17 00:00:00 2001 From: Emmanuel Grumbach Date: Tue, 17 Sep 2013 15:20:13 +0300 Subject: cfg80211: don't add p2p device while in RFKILL Since P2P device doesn't have a netdev associated to it, we cannot prevent the user to start it when in RFKILL. So refuse to even add it when in RFKILL. Signed-off-by: Emmanuel Grumbach Signed-off-by: Johannes Berg --- net/wireless/core.c | 2 -- net/wireless/core.h | 3 +++ 2 files changed, 3 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/wireless/core.c b/net/wireless/core.c index fe8d4f2be49b..aff959e5a1b3 100644 --- a/net/wireless/core.c +++ b/net/wireless/core.c @@ -958,8 +958,6 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb, case NETDEV_PRE_UP: if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype))) return notifier_from_errno(-EOPNOTSUPP); - if (rfkill_blocked(rdev->rfkill)) - return notifier_from_errno(-ERFKILL); ret = cfg80211_can_add_interface(rdev, wdev->iftype); if (ret) return notifier_from_errno(ret); diff --git a/net/wireless/core.h b/net/wireless/core.h index 9ad43c619c54..3159e9c284c5 100644 --- a/net/wireless/core.h +++ b/net/wireless/core.h @@ -411,6 +411,9 @@ static inline int cfg80211_can_add_interface(struct cfg80211_registered_device *rdev, enum nl80211_iftype iftype) { + if (rfkill_blocked(rdev->rfkill)) + return -ERFKILL; + return cfg80211_can_change_interface(rdev, NULL, iftype); } -- cgit v1.2.3-58-ga151 From f5563318ff1bde15b10e736e97ffce13be08bc1a Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 11 Oct 2013 14:47:05 +0200 Subject: wireless: radiotap: fix parsing buffer overrun When parsing an invalid radiotap header, the parser can overrun the buffer that is passed in because it doesn't correctly check 1) the minimum radiotap header size 2) the space for extended bitmaps The first issue doesn't affect any in-kernel user as they all check the minimum size before calling the radiotap function. The second issue could potentially affect the kernel if an skb is passed in that consists only of the radiotap header with a lot of extended bitmaps that extend past the SKB. In that case a read-only buffer overrun by at most 4 bytes is possible. Fix this by adding the appropriate checks to the parser. Cc: stable@vger.kernel.org Reported-by: Evan Huus Signed-off-by: Johannes Berg --- net/wireless/radiotap.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/wireless/radiotap.c b/net/wireless/radiotap.c index 7d604c06c3dc..a271c27fac77 100644 --- a/net/wireless/radiotap.c +++ b/net/wireless/radiotap.c @@ -97,6 +97,10 @@ int ieee80211_radiotap_iterator_init( struct ieee80211_radiotap_header *radiotap_header, int max_length, const struct ieee80211_radiotap_vendor_namespaces *vns) { + /* check the radiotap header can actually be present */ + if (max_length < sizeof(struct ieee80211_radiotap_header)) + return -EINVAL; + /* Linux only supports version 0 radiotap format */ if (radiotap_header->it_version) return -EINVAL; @@ -131,7 +135,8 @@ int ieee80211_radiotap_iterator_init( */ if ((unsigned long)iterator->_arg - - (unsigned long)iterator->_rtheader > + (unsigned long)iterator->_rtheader + + sizeof(uint32_t) > (unsigned long)iterator->_max_length) return -EINVAL; } -- cgit v1.2.3-58-ga151 From d86aa4f8ca58898ec6a94c0635da20b948171ed7 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 11 Oct 2013 15:47:06 +0200 Subject: mac80211: fix crash if bitrate calculation goes wrong If a frame's timestamp is calculated, and the bitrate calculation goes wrong and returns zero, the system will attempt to divide by zero and crash. Catch this case and print the rate information that the driver reported when this happens. Cc: stable@vger.kernel.org Reported-by: Thomas Lindroth Signed-off-by: Johannes Berg --- net/mac80211/util.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net') diff --git a/net/mac80211/util.c b/net/mac80211/util.c index 9c3200bcfc02..69e4ef5348a0 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -2238,6 +2238,10 @@ u64 ieee80211_calculate_rx_timestamp(struct ieee80211_local *local, } rate = cfg80211_calculate_bitrate(&ri); + if (WARN_ONCE(!rate, + "Invalid bitrate: flags=0x%x, idx=%d, vht_nss=%d\n", + status->flag, status->rate_idx, status->vht_nss)) + return 0; /* rewind from end of MPDU */ if (status->flag & RX_FLAG_MACTIME_END) -- cgit v1.2.3-58-ga151