kernel/git/stable/linux.git/net/mac80211/ht.c, branch linux-4.13.y

mac80211: fix deadlock in driver-managed RX BA session start

2017-10-05T07:47:25+00:00

commit bde59c475e0883e4c4294bcd9b9c7e08ae18c828 upstream. When an RX BA session is started by the driver, and it has to tell mac80211 about it, the corresponding bit in tid_rx_manage_offl gets set and the BA session work is scheduled. Upon testing this bit, it will call __ieee80211_start_rx_ba_session(), thus deadlocking as it already holds the ampdu_mlme.mtx, which that acquires again. Fix this by adding ___ieee80211_start_rx_ba_session(), a version of the function that requires the mutex already held. Fixes: 699cb58c8a52 ("mac80211: manage RX BA session offload without SKB queue") Reported-by: Matteo Croce Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman

networking: make skb_put & friends return void pointers

2017-06-16T15:48:39+00:00

It seems like a historic accident that these return unsigned char *, and in many places that means casts are required, more often than not. Make these functions (skb_put, __skb_put and pskb_put) return void * and remove all the casts across the tree, adding a (u8 *) cast only where the unsigned char pointer was used directly, all done with the following spatch: @@ expression SKB, LEN; typedef u8; identifier fn = { skb_put, __skb_put }; @@ - *(fn(SKB, LEN)) + *(u8 *)fn(SKB, LEN) @@ expression E, SKB, LEN; identifier fn = { skb_put, __skb_put }; type T; @@ - E = ((T *)(fn(SKB, LEN))) + E = fn(SKB, LEN) which actually doesn't cover pskb_put since there are only three users overall. A handful of stragglers were converted manually, notably a macro in drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many instances in net/bluetooth/hci_sock.c. In the former file, I also had to fix one whitespace problem spatch introduced. Signed-off-by: Johannes Berg Signed-off-by: David S. Miller

networking: convert many more places to skb_put_zero()

2017-06-16T15:48:35+00:00

There were many places that my previous spatch didn't find, as pointed out by yuan linyu in various patches. The following spatch found many more and also removes the now unnecessary casts: @@ identifier p, p2; expression len; expression skb; type t, t2; @@ ( -p = skb_put(skb, len); +p = skb_put_zero(skb, len); | -p = (t)skb_put(skb, len); +p = skb_put_zero(skb, len); ) ... when != p ( p2 = (t2)p; -memset(p2, 0, len); | -memset(p, 0, len); ) @@ type t, t2; identifier p, p2; expression skb; @@ t *p; ... ( -p = skb_put(skb, sizeof(t)); +p = skb_put_zero(skb, sizeof(t)); | -p = (t *)skb_put(skb, sizeof(t)); +p = skb_put_zero(skb, sizeof(t)); ) ... when != p ( p2 = (t2)p; -memset(p2, 0, sizeof(*p)); | -memset(p, 0, sizeof(*p)); ) @@ expression skb, len; @@ -memset(skb_put(skb, len), 0, len); +skb_put_zero(skb, len); Apply it to the tree (with one manual fixup to keep the comment in vxlan.c, which spatch removed.) Signed-off-by: Johannes Berg Signed-off-by: David S. Miller

mac80211: manage RX BA session offload without SKB queue

2017-06-08T12:16:29+00:00

Instead of using the SKB queue with the fake pkt_type for the offloaded RX BA session management, also handle this with the normal aggregation state machine worker. This also makes the use of this more reliable since it gets rid of the allocation of the fake skb. Combined with the previous patch, this finally allows us to get rid of the pkt_type hack entirely, so do that as well. Signed-off-by: Johannes Berg

mac80211: fix TX aggregation start/stop callback race

2017-05-30T07:08:40+00:00

When starting or stopping an aggregation session, one of the steps is that the driver calls back to mac80211 that the start/stop can proceed. This is handled by queueing up a fake SKB and processing it from the normal iface/sdata work. Since this isn't flushed when disassociating, the following race is possible: * associate * start aggregation session * driver callback * disassociate * associate again to the same AP * callback processing runs, leading to a WARN_ON() that the TID hadn't requested aggregation If the second association isn't to the same AP, there would only be a message printed ("Could not find station: "), but the same race could happen. Fix this by not going the whole detour with a fake SKB etc. but simply looking up the aggregation session in the driver callback, marking it with a START_CB/STOP_CB bit and then scheduling the regular aggregation work that will now process these bits as well. This also simplifies the code and gets rid of the whole problem with allocation failures of said skb, which could have left the session in limbo. Reported-by: Jouni Malinen Signed-off-by: Johannes Berg

mac80211: limit the A-MSDU Tx based on peer's capabilities

2016-02-24T08:04:20+00:00

In VHT, the specification allows to limit the number of MSDUs in an A-MSDU in the Extended Capabilities IE. There is also a limitation on the byte size in the VHT IE. In HT, the only limitation is on the byte size. Parse the capabilities from the peer and make them available to the driver. In HT, there is another limitation when a BA agreement is active: the byte size can't be greater than 4095. This is not enforced here. Signed-off-by: Emmanuel Grumbach Signed-off-by: Johannes Berg

mac80211: add VHT support for IBSS

2015-03-30T08:48:26+00:00

Add VHT support for IBSS. Drivers could activate this feature by setting NL80211_EXT_FEATURE_VHT_IBSS flag. Signed-off-by: Janusz Dziedzic Signed-off-by: Johannes Berg

mac80211: set Rx highest rate in ht_cap

2014-07-21T10:14:04+00:00

Set for completeness mostly, currently unused in the code. Signed-off-by: Arik Nemtsov Reviewed-by: Emmanuel Grumbach Signed-off-by: Johannes Berg

mac80211: support HT for TDLS stations

2014-07-21T10:14:04+00:00

Add the HT capabilities and HT operation information elements to TDLS setup packets where appropriate. Signed-off-by: Arik Nemtsov Reviewed-by: Emmanuel Grumbach Signed-off-by: Johannes Berg

mac80211: Allow HT capa override to add 40 MHz intolerant

2014-04-22T15:23:19+00:00

This can be useful for testing purposes to confirm valid AP behavior on HT 20/40 co-existence functionality. Signed-off-by: Jouni Malinen Signed-off-by: Johannes Berg