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* batman-adv: Avoid WARN_ON timing related checksSven Eckelmann2021-11-26
| | | | | | | | | | | | | | | | | | | | commit 9f460ae31c4435fd022c443a6029352217a16ac1 upstream. The soft/batadv interface for a queued OGM can be changed during the time the OGM was queued for transmission and when the OGM is actually transmitted by the worker. But WARN_ON must be used to denote kernel bugs and not to print simple warnings. A warning can simply be printed using pr_warn. Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Reported-by: syzbot+c0b807de416427ff3dd1@syzkaller.appspotmail.com Fixes: ef0a937f7a14 ("batman-adv: consider outgoing interface in OGM sending") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> [ bp: 4.4 backported: adjust context. ] Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Don't always reallocate the fragmentation skb headSven Eckelmann2021-11-26
| | | | | | | | | | | | | | | | | | | | | commit 992b03b88e36254e26e9a4977ab948683e21bd9f upstream. When a packet is fragmented by batman-adv, the original batman-adv header is not modified. Only a new fragmentation is inserted between the original one and the ethernet header. The code must therefore make sure that it has a writable region of this size in the skbuff head. But it is not useful to always reallocate the skbuff by this size even when there would be more than enough headroom still in the skb. The reallocation is just to costly during in this codepath. Fixes: ee75ed88879a ("batman-adv: Fragment and send skbs larger than mtu") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> [ bp: 4.4 backported: adjust context, switch back to old return type + labels ] Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Reserve needed_*room for fragmentsSven Eckelmann2021-11-26
| | | | | | | | | | | | | | | | | | | | commit c5cbfc87558168ef4c3c27ce36eba6b83391db19 upstream. The batadv net_device is trying to propagate the needed_headroom and needed_tailroom from the lower devices. This is needed to avoid cost intensive reallocations using pskb_expand_head during the transmission. But the fragmentation code split the skb's without adding extra room at the end/beginning of the various fragments. This reduced the performance of transmissions over complex scenarios (batadv on vxlan on wireguard) because the lower devices had to perform the reallocations at least once. Fixes: ee75ed88879a ("batman-adv: Fragment and send skbs larger than mtu") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> [ bp: 4.4 backported: adjust context. ] Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Consider fragmentation for needed_headroomSven Eckelmann2021-11-26
| | | | | | | | | | | | | | | | | commit 4ca23e2c2074465bff55ea14221175fecdf63c5f upstream. If a batman-adv packets has to be fragmented, then the original batman-adv packet header is not stripped away. Instead, only a new header is added in front of the packet after it was split. This size must be considered to avoid cost intensive reallocations during the transmission through the various device layers. Fixes: 7bca68c7844b ("batman-adv: Add lower layer needed_(head|tail)room to own ones") Reported-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: set .owner to THIS_MODULETaehee Yoo2021-11-26
| | | | | | | | | | | | | | | commit 14a2e551faea53d45bc11629a9dac88f88950ca7 upstream. If THIS_MODULE is not set, the module would be removed while debugfs is being used. It eventually makes kernel panic. Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> [ bp: 4.4 backported: switch to old filename. ] Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: mcast: fix duplicate mcast packets from BLA backbone to meshLinus Lüssing2021-11-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 2369e827046920ef0599e6a36b975ac5c0a359c2 upstream. Scenario: * Multicast frame send from BLA backbone gateways (multiple nodes with their bat0 bridged together, with BLA enabled) sharing the same LAN to nodes in the mesh Issue: * Nodes receive the frame multiple times on bat0 from the mesh, once from each foreign BLA backbone gateway which shares the same LAN with another For multicast frames via batman-adv broadcast packets coming from the same BLA backbone but from different backbone gateways duplicates are currently detected via a CRC history of previously received packets. However this CRC so far was not performed for multicast frames received via batman-adv unicast packets. Fixing this by appyling the same check for such packets, too. Room for improvements in the future: Ideally we would introduce the possibility to not only claim a client, but a complete originator, too. This would allow us to only send a multicast-in-unicast packet from a BLA backbone gateway claiming the node and by that avoid potential redundant transmissions in the first place. Fixes: fe2da6ff27c7 ("batman-adv: add broadcast duplicate check") Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> [ bp: 4.4 backported: adjust context, correct fixes line, switch back to int return type ] Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: mcast: fix duplicate mcast packets in BLA backbone from meshLinus Lüssing2021-11-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 74c09b7275126da1b642b90c9cdc3ae8b729ad4b upstream Scenario: * Multicast frame send from mesh to a BLA backbone (multiple nodes with their bat0 bridged together, with BLA enabled) Issue: * BLA backbone nodes receive the frame multiple times on bat0, once from mesh->bat0 and once from each backbone_gw from LAN For unicast, a node will send only to the best backbone gateway according to the TQ. However for multicast we currently cannot determine if multiple destination nodes share the same backbone if they don't share the same backbone with us. So we need to keep sending the unicasts to all backbone gateways and let the backbone gateways decide which one will forward the frame. We can use the CLAIM mechanism to make this decision. One catch: The batman-adv gateway feature for DHCP packets potentially sends multicast packets in the same batman-adv unicast header as the multicast optimizations code. And we are not allowed to drop those even if we did not claim the source address of the sender, as for such packets there is only this one multicast-in-unicast packet. How can we distinguish the two cases? The gateway feature uses a batman-adv unicast 4 address header. While the multicast-to-unicasts feature uses a simple, 3 address batman-adv unicast header. So let's use this to distinguish. Fixes: 2d3f6ccc4ea5 ("batman-adv: check incoming packet type for bla") Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue> Acked-by: Simon Wunderlich <sw@simonwunderlich.de> [ bp: 4.4 backported: adjust context, correct fixes line ] Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: mcast: fix duplicate mcast packets in BLA backbone from LANLinus Lüssing2021-11-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3236d215ad38a3f5372e65cd1e0a52cf93d3c6a2 upstream. Scenario: * Multicast frame send from a BLA backbone (multiple nodes with their bat0 bridged together, with BLA enabled) Issue: * BLA backbone nodes receive the frame multiple times on bat0 For multicast frames received via batman-adv broadcast packets the originator of the broadcast packet is checked before decapsulating and forwarding the frame to bat0 (batadv_bla_is_backbone_gw()-> batadv_recv_bcast_packet()). If it came from a node which shares the same BLA backbone with us then it is not forwarded to bat0 to avoid a loop. When sending a multicast frame in a non-4-address batman-adv unicast packet we are currently missing this check - and cannot do so because the batman-adv unicast packet has no originator address field. However, we can simply fix this on the sender side by only sending the multicast frame via unicasts to interested nodes which do not share the same BLA backbone with us. This also nicely avoids some unnecessary transmissions on mesh side. Note that no infinite loop was observed, probably because of dropping via batadv_interface_tx()->batadv_bla_tx(). However the duplicates still utterly confuse switches/bridges, ICMPv6 duplicate address detection and neighbor discovery and therefore leads to long delays before being able to establish TCP connections, for instance. And it also leads to the Linux bridge printing messages like: "br-lan: received packet on eth1 with own address as source address ..." Fixes: 1d8ab8d3c176 ("batman-adv: Modified forwarding behaviour for multicast packets") Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> [ bp: 4.4 backport: drop usage in non-existing batadv_mcast_forw_*, correct fixes line ] Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Prevent duplicated softif_vlan entrySven Eckelmann2021-11-26
| | | | | | | | | | | | | | | | | | | | | | | commit 94cb82f594ed86be303398d6dfc7640a6f1d45d4 upstream. The function batadv_softif_vlan_get is responsible for adding new softif_vlan to the softif_vlan_list. It first checks whether the entry already is in the list or not. If it is, then the creation of a new entry is aborted. But the lock for the list is only held when the list is really modified. This could lead to duplicated entries because another context could create an entry with the same key between the check and the list manipulation. The check and the manipulation of the list must therefore be in the same locked code section. Fixes: 5d2c05b21337 ("batman-adv: add per VLAN interface attribute framework") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> [ bp: 4.4 backport: switch back to atomic_t based reference counting. ] Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix multicast TT issues with bogus ROAM flagsLinus Lüssing2021-11-26
| | | | | | | | | | | | | | | | | | | | commit a44ebeff6bbd6ef50db41b4195fca87b21aefd20 upstream. When a (broken) node wrongly sends multicast TT entries with a ROAM flag then this causes any receiving node to drop all entries for the same multicast MAC address announced by other nodes, leading to packet loss. Fix this DoS vector by only storing TT sync flags. For multicast TT non-sync'ing flag bits like ROAM are unused so far anyway. Fixes: 1d8ab8d3c176 ("batman-adv: Modified forwarding behaviour for multicast packets") Reported-by: Leonardo Mörlein <me@irrelefant.net> Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> [ bp: 4.4 backported: adjust context, use old style to access flags ] Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Keep fragments equally sizedSven Eckelmann2021-11-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 1c2bcc766be44467809f1798cd4ceacafe20a852 upstream. The batman-adv fragmentation packets have the design problem that they cannot be refragmented and cannot handle padding by the underlying link. The latter often leads to problems when networks are incorrectly configured and don't use a common MTU. The sender could for example fragment a 1271 byte frame (plus external ethernet header (14) and batadv unicast header (10)) to fit in a 1280 bytes large MTU of the underlying link (max. 1294 byte frames). This would create a 1294 bytes large frame (fragment 2) and a 55 bytes large frame (fragment 1). The extra 54 bytes are the fragment header (20) added to each fragment and the external ethernet header (14) for the second fragment. Let us assume that the next hop is then not able to transport 1294 bytes to its next hop. The 1294 byte large frame will be dropped but the 55 bytes large fragment will still be forwarded to its destination. Or let us assume that the underlying hardware requires that each frame has a minimum size (e.g. 60 bytes). Then it will pad the 55 bytes frame to 60 bytes. The receiver of the 60 bytes frame will no longer be able to correctly assemble the two frames together because it is not aware that 5 bytes of the 60 bytes frame are padding and don't belong to the reassembled frame. This can partly be avoided by splitting frames more equally. In this example, the 675 and 674 bytes large fragment frames could both potentially reach its destination without being too large or too small. Reported-by: Martin Weinelt <martin@darmstadt.freifunk.net> Fixes: ee75ed88879a ("batman-adv: Fragment and send skbs larger than mtu") Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> [ bp: 4.4 backported: adjust context, switch back to old return type + labels ] Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net: batman-adv: fix error handlingPavel Skripkin2021-11-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6f68cd634856f8ca93bafd623ba5357e0f648c68 upstream. Syzbot reported ODEBUG warning in batadv_nc_mesh_free(). The problem was in wrong error handling in batadv_mesh_init(). Before this patch batadv_mesh_init() was calling batadv_mesh_free() in case of any batadv_*_init() calls failure. This approach may work well, when there is some kind of indicator, which can tell which parts of batadv are initialized; but there isn't any. All written above lead to cleaning up uninitialized fields. Even if we hide ODEBUG warning by initializing bat_priv->nc.work, syzbot was able to hit GPF in batadv_nc_purge_paths(), because hash pointer in still NULL. [1] To fix these bugs we can unwind batadv_*_init() calls one by one. It is good approach for 2 reasons: 1) It fixes bugs on error handling path 2) It improves the performance, since we won't call unneeded batadv_*_free() functions. So, this patch makes all batadv_*_init() clean up all allocated memory before returning with an error to no call correspoing batadv_*_free() and open-codes batadv_mesh_free() with proper order to avoid touching uninitialized fields. Link: https://lore.kernel.org/netdev/000000000000c87fbd05cef6bcb0@google.com/ [1] Reported-and-tested-by: syzbot+28b0702ada0bf7381f58@syzkaller.appspotmail.com Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> Acked-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: initialize "struct batadv_tvlv_tt_vlan_data"->reserved fieldTetsuo Handa2021-04-16
| | | | | | | | | | | | | | | | | | | | | | commit 08c27f3322fec11950b8f1384aa0f3b11d028528 upstream. KMSAN found uninitialized value at batadv_tt_prepare_tvlv_local_data() [1], for commit ced72933a5e8ab52 ("batman-adv: use CRC32C instead of CRC16 in TT code") inserted 'reserved' field into "struct batadv_tvlv_tt_data" and commit 7ea7b4a142758dea ("batman-adv: make the TT CRC logic VLAN specific") moved that field to "struct batadv_tvlv_tt_vlan_data" but left that field uninitialized. [1] https://syzkaller.appspot.com/bug?id=07f3e6dba96f0eb3cabab986adcd8a58b9bdbe9d Reported-by: syzbot <syzbot+50ee810676e6a089487b@syzkaller.appspotmail.com> Tested-by: syzbot <syzbot+50ee810676e6a089487b@syzkaller.appspotmail.com> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Fixes: ced72933a5e8ab52 ("batman-adv: use CRC32C instead of CRC16 in TT code") Fixes: 7ea7b4a142758dea ("batman-adv: make the TT CRC logic VLAN specific") Acked-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: mcast/TT: fix wrongly dropped or rerouted packetsLinus Lüssing2020-10-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 7dda5b3384121181c4e79f6eaeac2b94c0622c8d ] The unicast packet rerouting code makes several assumptions. For instance it assumes that there is always exactly one destination in the TT. This breaks for multicast frames in a unicast packets in several ways: For one thing if there is actually no TT entry and the destination node was selected due to the multicast tvlv flags it announced. Then an intermediate node will wrongly drop the packet. For another thing if there is a TT entry but the TTVN of this entry is newer than the originally addressed destination node: Then the intermediate node will wrongly redirect the packet, leading to duplicated multicast packets at a multicast listener and missing packets at other multicast listeners or multicast routers. Fixing this by not applying the unicast packet rerouting to batman-adv unicast packets with a multicast payload. We are not able to detect a roaming multicast listener at the moment and will just continue to send the multicast frame to both the new and old destination for a while in case of such a roaming multicast listener. Fixes: a73105b8d4c7 ("batman-adv: improved client announcement mechanism") Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
* batman-adv: bla: fix type misuse for backbone_gw hash indexingLinus Lüssing2020-10-01
| | | | | | | | | | | | | | | | | | | | [ Upstream commit 097930e85f90f252c44dc0d084598265dd44ca48 ] It seems that due to a copy & paste error the void pointer in batadv_choose_backbone_gw() is cast to the wrong type. Fixing this by using "struct batadv_bla_backbone_gw" instead of "struct batadv_bla_claim" which better matches the caller's side. For now it seems that we were lucky because the two structs both have their orig/vid and addr/vid in the beginning. However I stumbled over this issue when I was trying to add some debug variables in front of "orig" in batadv_backbone_gw, which caused hash lookups to fail. Fixes: 07568d0369f9 ("batman-adv: don't rely on positions in struct for hashing") Signed-off-by: Linus Lüssing <ll@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* batman-adv: bla: use netif_rx_ni when not in interrupt contextJussi Kivilinna2020-09-12
| | | | | | | | | | | | | | | [ Upstream commit 279e89b2281af3b1a9f04906e157992c19c9f163 ] batadv_bla_send_claim() gets called from worker thread context through batadv_bla_periodic_work(), thus netif_rx_ni needs to be used in that case. This fixes "NOHZ: local_softirq_pending 08" log messages seen when batman-adv is enabled. Fixes: 23721387c409 ("batman-adv: add basic bridge loop avoidance code") Signed-off-by: Jussi Kivilinna <jussi.kivilinna@haltian.com> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
* batman-adv: Avoid uninitialized chaddr when handling DHCPSven Eckelmann2020-09-12
| | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 303216e76dcab6049c9d42390b1032f0649a8206 ] The gateway client code can try to optimize the delivery of DHCP packets to avoid broadcasting them through the whole mesh. But also transmissions to the client can be optimized by looking up the destination via the chaddr of the DHCP packet. But the chaddr is currently only done when chaddr is fully inside the non-paged area of the skbuff. Otherwise it will not be initialized and the unoptimized path should have been taken. But the implementation didn't handle this correctly. It didn't retrieve the correct chaddr but still tried to perform the TT lookup with this uninitialized memory. Reported-by: syzbot+ab16e463b903f5a37036@syzkaller.appspotmail.com Fixes: 6c413b1c22a2 ("batman-adv: send every DHCP packet as bat-unicast") Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
* batman-adv: fix batadv_nc_random_weight_tqGeorge Spelvin2020-05-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit fd0c42c4dea54335967c5a86f15fc064235a2797 upstream. and change to pseudorandom numbers, as this is a traffic dithering operation that doesn't need crypto-grade. The previous code operated in 4 steps: 1. Generate a random byte 0 <= rand_tq <= 255 2. Multiply it by BATADV_TQ_MAX_VALUE - tq 3. Divide by 255 (= BATADV_TQ_MAX_VALUE) 4. Return BATADV_TQ_MAX_VALUE - rand_tq This would apperar to scale (BATADV_TQ_MAX_VALUE - tq) by a random value between 0/255 and 255/255. But! The intermediate value between steps 3 and 4 is stored in a u8 variable. So it's truncated, and most of the time, is less than 255, after which the division produces 0. Specifically, if tq is odd, the product is always even, and can never be 255. If tq is even, there's exactly one random byte value that will produce a product byte of 255. Thus, the return value is 255 (511/512 of the time) or 254 (1/512 of the time). If we assume that the truncation is a bug, and the code is meant to scale the input, a simpler way of looking at it is that it's returning a random value between tq and BATADV_TQ_MAX_VALUE, inclusive. Well, we have an optimized function for doing just that. Fixes: 3c12de9a5c75 ("batman-adv: network coding - code and transmit packets if possible") Signed-off-by: George Spelvin <lkml@sdf.org> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: replace WARN with rate limited output on non-existing VLANSimon Wunderlich2020-05-10
| | | | | | | | | | | | | | | | | | | | | | | commit 0b3dd7dfb81ad8af53791ea2bb64b83bac1b7d32 upstream. If a VLAN tagged frame is received and the corresponding VLAN is not configured on the soft interface, it will splat a WARN on every packet received. This is a quite annoying behaviour for some scenarios, e.g. if bat0 is bridged with eth0, and there are arbitrary VLAN tagged frames from Ethernet coming in without having any VLAN configuration on bat0. The code should probably create vlan objects on the fly and transparently transport these VLAN-tagged Ethernet frames, but until this is done, at least the WARN splat should be replaced by a rate limited output. Fixes: 354136bcc3c4 ("batman-adv: fix kernel crash due to missing NULL checks") Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix lockdep annotation of batadv_tlv_container_removeSven Eckelmann2020-05-10
| | | | | | | | | | | | | | commit 008a374487070a391c12aa39288fd8511f822cab upstream. The function handles tlv containers and not tlv handlers. Thus the lockdep_assert_held has to check for the container_list lock. Fixes: 2c72d655b044 ("batman-adv: Annotate deleting functions with external lock via lockdep") Signed-off-by: Sven Eckelmann <sven@open-mesh.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Don't schedule OGM for disabled interfaceSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | A transmission scheduling for an interface which is currently dropped by batadv_iv_ogm_iface_disable could still be in progress. The B.A.T.M.A.N. V is simply cancelling the workqueue item in an synchronous way but this is not possible with B.A.T.M.A.N. IV because the OGM submissions are intertwined. Instead it has to stop submitting the OGM when it detect that the buffer pointer is set to NULL. Reported-by: syzbot+a98f2016f40b9cd3818a@syzkaller.appspotmail.com Reported-by: syzbot+ac36b6a33c28a491e929@syzkaller.appspotmail.com Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Signed-off-by: Sven Eckelmann <sven@narfation.org> Cc: Hillf Danton <hdanton@sina.com> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Avoid free/alloc race when handling OGM bufferSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | | | commit 40e220b4218bb3d278e5e8cc04ccdfd1c7ff8307 upstream. Each slave interface of an B.A.T.M.A.N. IV virtual interface has an OGM packet buffer which is initialized using data from netdevice notifier and other rtnetlink related hooks. It is sent regularly via various slave interfaces of the batadv virtual interface and in this process also modified (realloced) to integrate additional state information via TVLV containers. It must be avoided that the worker item is executed without a common lock with the netdevice notifier/rtnetlink helpers. Otherwise it can either happen that half modified/freed data is sent out or functions modifying the OGM buffer try to access already freed memory regions. Reported-by: syzbot+0cc629f19ccb8534935b@syzkaller.appspotmail.com Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Only read OGM tvlv_len after buffer len checkSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | | | commit a15d56a60760aa9dbe26343b9a0ac5228f35d445 upstream. Multiple batadv_ogm_packet can be stored in an skbuff. The functions batadv_iv_ogm_send_to_if()/batadv_iv_ogm_receive() use batadv_iv_ogm_aggr_packet() to check if there is another additional batadv_ogm_packet in the skb or not before they continue processing the packet. The length for such an OGM is BATADV_OGM_HLEN + batadv_ogm_packet->tvlv_len. The check must first check that at least BATADV_OGM_HLEN bytes are available before it accesses tvlv_len (which is part of the header. Otherwise it might try read outside of the currently available skbuff to get the content of tvlv_len. Fixes: ef26157747d4 ("batman-adv: tvlv - basic infrastructure") Reported-by: syzbot+355cab184197dbbfa384@syzkaller.appspotmail.com Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Reduce tt_global hash refcnt only for removed entrySven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit f131a56880d10932931e74773fb8702894a94a75 upstream. The batadv_hash_remove is a function which searches the hashtable for an entry using a needle, a hashtable bucket selection function and a compare function. It will lock the bucket list and delete an entry when the compare function matches it with the needle. It returns the pointer to the hlist_node which matches or NULL when no entry matches the needle. The batadv_tt_global_free is not itself protected in anyway to avoid that any other function is modifying the hashtable between the search for the entry and the call to batadv_hash_remove. It can therefore happen that the entry either doesn't exist anymore or an entry was deleted which is not the same object as the needle. In such an situation, the reference counter (for the reference stored in the hashtable) must not be reduced for the needle. Instead the reference counter of the actually removed entry has to be reduced. Otherwise the reference counter will underflow and the object might be freed before all its references were dropped. The kref helpers reported this problem as: refcount_t: underflow; use-after-free. Fixes: 7683fdc1e886 ("batman-adv: protect the local and the global trans-tables with rcu") Reported-by: Martin Weinelt <martin@linuxlounge.net> Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Reduce tt_local hash refcnt only for removed entrySven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3d65b9accab4a7ed5038f6df403fbd5e298398c7 upstream. The batadv_hash_remove is a function which searches the hashtable for an entry using a needle, a hashtable bucket selection function and a compare function. It will lock the bucket list and delete an entry when the compare function matches it with the needle. It returns the pointer to the hlist_node which matches or NULL when no entry matches the needle. The batadv_tt_local_remove is not itself protected in anyway to avoid that any other function is modifying the hashtable between the search for the entry and the call to batadv_hash_remove. It can therefore happen that the entry either doesn't exist anymore or an entry was deleted which is not the same object as the needle. In such an situation, the reference counter (for the reference stored in the hashtable) must not be reduced for the needle. Instead the reference counter of the actually removed entry has to be reduced. Otherwise the reference counter will underflow and the object might be freed before all its references were dropped. The kref helpers reported this problem as: refcount_t: underflow; use-after-free. Fixes: ef72706a0543 ("batman-adv: protect tt_local_entry from concurrent delete events") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Reduce claim hash refcnt only for removed entrySven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 4ba104f468bbfc27362c393815d03aa18fb7a20f upstream. The batadv_hash_remove is a function which searches the hashtable for an entry using a needle, a hashtable bucket selection function and a compare function. It will lock the bucket list and delete an entry when the compare function matches it with the needle. It returns the pointer to the hlist_node which matches or NULL when no entry matches the needle. The batadv_bla_del_claim is not itself protected in anyway to avoid that any other function is modifying the hashtable between the search for the entry and the call to batadv_hash_remove. It can therefore happen that the entry either doesn't exist anymore or an entry was deleted which is not the same object as the needle. In such an situation, the reference counter (for the reference stored in the hashtable) must not be reduced for the needle. Instead the reference counter of the actually removed entry has to be reduced. Otherwise the reference counter will underflow and the object might be freed before all its references were dropped. The kref helpers reported this problem as: refcount_t: underflow; use-after-free. Fixes: 23721387c409 ("batman-adv: add basic bridge loop avoidance code") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Prevent duplicated tvlv handlerSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | commit ae3cdc97dc10c7a3b31f297dab429bfb774c9ccb upstream. The function batadv_tvlv_handler_register is responsible for adding new tvlv_handler to the handler_list. It first checks whether the entry already is in the list or not. If it is, then the creation of a new entry is aborted. But the lock for the list is only held when the list is really modified. This could lead to duplicated entries because another context could create an entry with the same key between the check and the list manipulation. The check and the manipulation of the list must therefore be in the same locked code section. Fixes: ef26157747d4 ("batman-adv: tvlv - basic infrastructure") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Prevent duplicated global TT entrySven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | commit e7136e48ffdfb9f37b0820f619380485eb407361 upstream. The function batadv_tt_global_orig_entry_add is responsible for adding new tt_orig_list_entry to the orig_list. It first checks whether the entry already is in the list or not. If it is, then the creation of a new entry is aborted. But the lock for the list is only held when the list is really modified. This could lead to duplicated entries because another context could create an entry with the same key between the check and the list manipulation. The check and the manipulation of the list must therefore be in the same locked code section. Fixes: d657e621a0f5 ("batman-adv: add reference counting for type batadv_tt_orig_list_entry") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Prevent duplicated nc_node entrySven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | | commit fa122fec8640eb7186ce5a41b83a4c1744ceef8f upstream. The function batadv_nc_get_nc_node is responsible for adding new nc_nodes to the in_coding_list and out_coding_list. It first checks whether the entry already is in the list or not. If it is, then the creation of a new entry is aborted. But the lock for the list is only held when the list is really modified. This could lead to duplicated entries because another context could create an entry with the same key between the check and the list manipulation. The check and the manipulation of the list must therefore be in the same locked code section. Fixes: d56b1705e28c ("batman-adv: network coding - detect coding nodes and remove these after timeout") Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Prevent duplicated gateway_node entrySven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | commit dff9bc42ab0b2d38c5e90ddd79b238fed5b4c7ad upstream. The function batadv_gw_node_add is responsible for adding new gw_node to the gateway_list. It is expecting that the caller already checked that there is not already an entry with the same key or not. But the lock for the list is only held when the list is really modified. This could lead to duplicated entries because another context could create an entry with the same key between the check and the list manipulation. The check and the manipulation of the list must therefore be in the same locked code section. Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Avoid storing non-TT-sync flags on singular entries tooLinus Lüssing2020-03-20
| | | | | | | | | | | | | | | | | | | | | commit 4a519b83da16927fb98fd32b0f598e639d1f1859 upstream. Since commit 54e22f265e87 ("batman-adv: fix TT sync flag inconsistencies") TT sync flags and TT non-sync'd flags are supposed to be stored separately. The previous patch missed to apply this separation on a TT entry with only a single TT orig entry. This is a minor fix because with only a single TT orig entry the DDoS issue the former patch solves does not apply. Fixes: 54e22f265e87 ("batman-adv: fix TT sync flag inconsistencies") Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix debugfs path for renamed softifSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6da7be7d24b2921f8215473ba7552796dff05fe1 upstream. batman-adv is creating special debugfs directories in the init net_namespace for each created soft-interface (batadv net_device). But it is possible to rename a net_device to a completely different name then the original one. It can therefore happen that a user registers a new batadv net_device with the name "bat0". batman-adv is then also adding a new directory under $debugfs/batman-adv/ with the name "wlan0". The user then decides to rename this device to "bat1" and registers a different batadv device with the name "bat0". batman-adv will then try to create a directory with the name "bat0" under $debugfs/batman-adv/ again. But there already exists one with this name under this path and thus this fails. batman-adv will detect a problem and rollback the registering of this device. batman-adv must therefore take care of renaming the debugfs directories for soft-interfaces whenever it detects such a net_device rename. Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix debugfs path for renamed hardifSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 36dc621ceca1be3ec885aeade5fdafbbcc452a6d upstream. batman-adv is creating special debugfs directories in the init net_namespace for each valid hard-interface (net_device). But it is possible to rename a net_device to a completely different name then the original one. It can therefore happen that a user registers a new net_device which gets the name "wlan0" assigned by default. batman-adv is also adding a new directory under $debugfs/batman-adv/ with the name "wlan0". The user then decides to rename this device to "wl_pri" and registers a different device. The kernel may now decide to use the name "wlan0" again for this new device. batman-adv will detect it as a valid net_device and tries to create a directory with the name "wlan0" under $debugfs/batman-adv/. But there already exists one with this name under this path and thus this fails. batman-adv will detect a problem and rollback the registering of this device. batman-adv must therefore take care of renaming the debugfs directories for hard-interfaces whenever it detects such a net_device rename. Fixes: 5bc7c1eb44f2 ("batman-adv: add debugfs structure for information per interface") Reported-by: John Soros <sorosj@gmail.com> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: prevent TT request storms by not sending inconsistent TT TLVLsMarek Lindner2020-03-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit 16116dac23396e73c01eeee97b102e4833a4b205 upstream. A translation table TVLV changset sent with an OGM consists of a number of headers (one per VLAN) plus the changeset itself (addition and/or deletion of entries). The per-VLAN headers are used by OGM recipients for consistency checks. Said consistency check might determine that a full translation table request is needed to restore consistency. If the TT sender adds per-VLAN headers of empty VLANs into the OGM, recipients are led to believe to have reached an inconsistent state and thus request a full table update. The full table does not contain empty VLANs (due to missing entries) the cycle restarts when the next OGM is issued. Consequently, when the translation table TVLV headers are composed, empty VLANs are to be excluded. Fixes: 21a57f6e7a3b ("batman-adv: make the TT CRC logic VLAN specific") Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix TT sync flags for intermediate TT responsesLinus Lüssing2020-03-20
| | | | | | | | | | | | | | | | | | | | | | | | commit 7072337e52b3e9d5460500d8dc9cbc1ba2db084c upstream. The previous TT sync fix so far only fixed TT responses issued by the target node directly. So far, TT responses issued by intermediate nodes still lead to the wrong flags being added, leading to CRC mismatches. This behaviour was observed at Freifunk Hannover in a 800 nodes setup where a considerable amount of nodes were still infected with 'WI' TT flags even with (most) nodes having the previous TT sync fix applied. I was able to reproduce the issue with intermediate TT responses in a four node test setup and this patch fixes this issue by ensuring to use the per originator instead of the summarized, OR'd ones. Fixes: e9c00136a475 ("batman-adv: fix tt_global_entries flags update") Reported-by: Leonardo Mörlein <me@irrelefant.net> Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Avoid race in TT TVLV allocator helperSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 8ba0f9bd3bdea1058c2b2676bec7905724418e40 upstream. The functions batadv_tt_prepare_tvlv_local_data and batadv_tt_prepare_tvlv_global_data are responsible for preparing a buffer which can be used to store the TVLV container for TT and add the VLAN information to it. This will be done in three phases: 1. count the number of VLANs and their entries 2. allocate the buffer using the counters from the previous step and limits from the caller (parameter tt_len) 3. insert the VLAN information to the buffer The step 1 and 3 operate on a list which contains the VLANs. The access to these lists must be protected with an appropriate lock or otherwise they might operate on on different entries. This could for example happen when another context is adding VLAN entries to this list. This could lead to a buffer overflow in these functions when enough entries were added between step 1 and 3 to the VLAN lists that the buffer room for the entries (*tt_change) is smaller then the now required extra buffer for new VLAN entries. Fixes: 7ea7b4a14275 ("batman-adv: make the TT CRC logic VLAN specific") Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix skbuff rcsum on packet rerouteSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | commit fc04fdb2c8a894283259f5621d31d75610701091 upstream. batadv_check_unicast_ttvn may redirect a packet to itself or another originator. This involves rewriting the ttvn and the destination address in the batadv unicast header. These field were not yet pulled (with skb rcsum update) and thus any change to them also requires a change in the receive checksum. Reported-by: Matthias Schiffer <mschiffer@universe-factory.net> Fixes: a73105b8d4c7 ("batman-adv: improved client announcement mechanism") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: update data pointers after skb_cow()Matthias Schiffer2020-03-20
| | | | | | | | | | | | | commit bc44b78157f621ff2a2618fe287a827bcb094ac4 upstream. batadv_check_unicast_ttvn() calls skb_cow(), so pointers into the SKB data must be (re)set after calling it. The ethhdr variable is dropped altogether. Fixes: 78fc6bbe0aca ("batman-adv: add UNICAST_4ADDR packet type") Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix internal interface indices typesSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit f22e08932c2960f29b5e828e745c9f3fb7c1bb86 upstream. batman-adv uses internal indices for each enabled and active interface. It is currently used by the B.A.T.M.A.N. IV algorithm to identifify the correct position in the ogm_cnt bitmaps. The type for the number of enabled interfaces (which defines the next interface index) was set to char. This type can be (depending on the architecture) either signed (limiting batman-adv to 127 active slave interfaces) or unsigned (limiting batman-adv to 255 active slave interfaces). This limit was not correctly checked when an interface was enabled and thus an overflow happened. This was only catched on systems with the signed char type when the B.A.T.M.A.N. IV code tried to resize its counter arrays with a negative size. The if_num interface index was only a s16 and therefore significantly smaller than the ifindex (int) used by the code net code. Both &batadv_hard_iface->if_num and &batadv_priv->num_ifaces must be (unsigned) int to support the same number of slave interfaces as the net core code. And the interface activation code must check the number of active slave interfaces to avoid integer overflows. Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix lock for ogm cnt access in batadv_iv_ogm_calc_tqSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | commit 5ba7dcfe77037b67016263ea597a8b431692ecab upstream. The originator node object orig_neigh_node is used to when accessing the bcast_own(_sum) and real_packet_count information. The access to them has to be protected with the spinlock in orig_neigh_node. But the function uses the lock in orig_node instead. This is incorrect because they could be two different originator node objects. Fixes: 0ede9f41b217 ("batman-adv: protect bit operations to count OGMs with spinlock") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: fix TT sync flag inconsistenciesLinus Lüssing2020-03-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 54e22f265e872ae140755b3318521d400a094605 upstream. This patch fixes an issue in the translation table code potentially leading to a TT Request + Response storm. The issue may occur for nodes involving BLA and an inconsistent configuration of the batman-adv AP isolation feature. However, since the new multicast optimizations, a single, malformed packet may lead to a mesh-wide, persistent Denial-of-Service, too. The issue occurs because nodes are currently OR-ing the TT sync flags of all originators announcing a specific MAC address via the translation table. When an intermediate node now receives a TT Request and wants to answer this on behalf of the destination node, then this intermediate node now responds with an altered flag field and broken CRC. The next OGM of the real destination will lead to a CRC mismatch and triggering a TT Request and Response again. Furthermore, the OR-ing is currently never undone as long as at least one originator announcing the according MAC address remains, leading to the potential persistency of this issue. This patch fixes this issue by storing the flags used in the CRC calculation on a a per TT orig entry basis to be able to respond with the correct, original flags in an intermediate TT Response for one thing. And to be able to correctly unset sync flags once all nodes announcing a sync flag vanish for another. Fixes: e9c00136a475 ("batman-adv: fix tt_global_entries flags update") Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue> Acked-by: Antonio Quartulli <a@unstable.cc> [sw: typo in commit message] Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix rx packet/bytes stats on local ARP replySven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | commit 36d4d68cd658d914ef73ac845705c4a89e7d9e2f upstream. The stats are generated by batadv_interface_stats and must not be stored directly in the net_device stats member variable. The batadv_priv bat_counters information is assembled when ndo_get_stats is called. The stats previously stored in net_device::stats is then overwritten. The batman-adv counters must therefore be increased when an ARP packet is answered locally via the distributed arp table. Fixes: c384ea3ec930 ("batman-adv: Distributed ARP Table - add snooping functions for ARP messages") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix transmission of final, 16th fragmentLinus Lüssing2020-03-20
| | | | | | | | | | | | | | | | | | | | | | commit 51c6b429c0c95e67edd1cb0b548c5cf6a6604763 upstream. Trying to split and transmit a unicast packet in 16 parts will fail for the final fragment: After having sent the 15th one with a frag_packet.no index of 14, we will increase the the index to 15 - and return with an error code immediately, even though one more fragment is due for transmission and allowed. Fixing this issue by moving the check before incrementing the index. While at it, adding an unlikely(), because the check is actually more of an assertion. Fixes: ee75ed88879a ("batman-adv: Fragment and send skbs larger than mtu") Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix double free during fragment merge errorSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | | | commit 248e23b50e2da0753f3b5faa068939cbe9f8a75a upstream. The function batadv_frag_skb_buffer was supposed not to consume the skbuff on errors. This was followed in the helper function batadv_frag_insert_packet when the skb would potentially be inserted in the fragment queue. But it could happen that the next helper function batadv_frag_merge_packets would try to merge the fragments and fail. This results in a kfree_skb of all the enqueued fragments (including the just inserted one). batadv_recv_frag_packet would detect the error in batadv_frag_skb_buffer and try to free the skb again. The behavior of batadv_frag_skb_buffer (and its helper batadv_frag_insert_packet) must therefore be changed to always consume the skbuff to have a common behavior and avoid the double kfree_skb. Fixes: 610bfc6bc99b ("batman-adv: Receive fragmented packets and merge") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Add missing refcnt for last_candidateSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | commit 936523441bb64cdc9a5b263e8fd2782e70313a57 upstream. batadv_find_router dereferences last_bonding_candidate from orig_node without making sure that it has a valid reference. This reference has to be retrieved by increasing the reference counter while holding neigh_list_lock. The lock is required to avoid that batadv_last_bonding_replace removes the current last_bonding_candidate, reduces the reference counter and maybe destroys the object in this process. Fixes: f3b3d9018975 ("batman-adv: add bonding again") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix speedy join in gateway client modeSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | | | commit d1fe176ca51fa3cb35f70c1d876d9a090e9befce upstream. Speedy join only works when the received packet is either broadcast or an 4addr unicast packet. Thus packets converted from broadcast to unicast via the gateway handling code have to be converted to 4addr packets to allow the receiving gateway server to add the sender address as temporary entry to the translation table. Not doing it will make the batman-adv gateway server drop the DHCP response in many situations because it doesn't yet have the TT entry for the destination of the DHCP response. Fixes: 371351731e9c ("batman-adv: change interface_rx to get orig node") Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Free last_bonding_candidate on release of orig_nodeSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | commit cbef1e102003edb236c6b2319ab269ccef963731 upstream. The orig_ifinfo reference counter for last_bonding_candidate in batadv_orig_node has to be reduced when an originator node is released. Otherwise the orig_ifinfo is leaked and the reference counter the netdevice is not reduced correctly. Fixes: f3b3d9018975 ("batman-adv: add bonding again") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix reference leak in batadv_find_routerSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | commit 15c2ed753cd9e3e746472deab8151337a5b6da56 upstream. The replacement of last_bonding_candidate in batadv_orig_node has to be an atomic operation. Otherwise it is possible that the reference counter of a batadv_orig_ifinfo is reduced which was no longer the last_bonding_candidate when the new candidate is added. This can either lead to an invalid memory access or to reference leaks which make it impossible to an interface which was added to batman-adv. Fixes: f3b3d9018975 ("batman-adv: add bonding again") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: Fix non-atomic bla_claim::backbone_gw accessSven Eckelmann2020-03-20
| | | | | | | | | | | | | | | | | | | commit 3db0decf1185357d6ab2256d0dede1ca9efda03d upstream. The pointer batadv_bla_claim::backbone_gw can be changed at any time. Therefore, access to it must be protected to ensure that two function accessing the same backbone_gw are actually accessing the same. This is especially important when the crc_lock is used or when the backbone_gw of a claim is exchanged. Not doing so leads to invalid memory access and/or reference leaks. Fixes: 23721387c409 ("batman-adv: add basic bridge loop avoidance code") Fixes: 5a1dd8a4773d ("batman-adv: lock crc access in bridge loop avoidance") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* batman-adv: lock crc access in bridge loop avoidanceSimon Wunderlich2020-03-20
| | | | | | | | | | | | | | | | | | | | commit 5a1dd8a4773d4c24e925cc6154826d555a85c370 upstream. We have found some networks in which nodes were constantly requesting other nodes BLA claim tables to synchronize, just to ask for that again once completed. The reason was that the crc checksum of the asked nodes were out of sync due to missing locking and multiple writes to the same crc checksum when adding/removing entries. Therefore the asked nodes constantly reported the wrong crc, which caused repeating requests. To avoid multiple functions changing a backbone gateways crc entry at the same time, lock it using a spinlock. Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Tested-by: Alfons Name <AlfonsName@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>