Handle the case when dev_alloc_skb returns NULL.

Cc: stable@vger.kernel.org
Fixes: 2b67f944f88c2 ("cfg80211: reuse existing page fragments in A-MSDU rx")
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>

The PDU length of incoming LLC frames is set to the total skb payload size
in __ieee80211_data_to_8023() of net/wireless/util.c which incorrectly
includes the length of the IEEE 802.11 header.

The resulting LLC frame header has a too large PDU length, causing the
llc_fixup_skb() function of net/llc/llc_input.c to reject the incoming
skb, effectively breaking STP.

Solve the problem by properly substracting the IEEE 802.11 frame header size
from the PDU length, allowing the LLC processor to pick up the incoming
control messages.

Special thanks to Gerry Rozema for tracking down the regression and proposing
a suitable patch.

Fixes: 2d1c304cb2d5 ("cfg80211: add function for 802.3 conversion with separate output buffer")
Cc: stable@vger.kernel.org
Reported-by: Gerry Rozema <gerryr@rozeware.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>

page_reference manipulation functions are introduced to track down
reference count change of the page.  Use it instead of direct
modification of _count.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Sunil Goutham <sgoutham@cavium.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

There's no harm in having drivers read the list, since they can
use RCU protection or RTNL locking; allow this to not require
each and every driver to also implement its own bookkeeping.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Since cfg80211 maintains separate BSS table entries for APs if the same
BSSID, SSID pair is seen on multiple channels, it is possible that it
can map the current_bss to a BSS entry on the wrong channel. This
current_bss will not get flushed unless disconnected and cfg80211
reports a wrong channel as the associated channel.

Fix this by introducing a new cfg80211_connect_bss() function which is
similar to cfg80211_connect_result(), but it includes an additional
parameter: the bss the STA is connected to. This allows drivers to
provide the exact bss entry that matches the BSS to which the connection
was completed.

Reviewed-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Vidyullatha Kanchanapally <vkanchan@qti.qualcomm.com>
Signed-off-by: Sunil Dutt <usdutt@qti.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This enum is already perfectly aliased to enum nl80211_band, and
the only reason for it is that we get IEEE80211_NUM_BANDS out of
it. There's no really good reason to not declare the number of
bands in nl80211 though, so do that and remove the cfg80211 one.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Since offset is zero, it's not necessary to use set function. Reset
function is straightforward, and will remove the unnecessary add
operation in set function.

Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This massively reduces data copying and thus improves rx performance

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

reuse_skb is set to true if the code decides to use the last segment.
Fixes a memory leak

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>