linux-toradex.git/net/batman-adv, branch v5.3.2

batman-adv: Only read OGM2 tvlv_len after buffer len check

2019-08-23T16:20:31+00:00

Multiple batadv_ogm2_packet can be stored in an skbuff. The functions
batadv_v_ogm_send_to_if() uses batadv_v_ogm_aggr_packet() to check if there
is another additional batadv_ogm2_packet in the skb or not before they
continue processing the packet.

The length for such an OGM2 is BATADV_OGM2_HLEN +
batadv_ogm2_packet->tvlv_len. The check must first check that at least
BATADV_OGM2_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: 9323158ef9f4 ("batman-adv: OGMv2 - implement originators logic")
Signed-off-by: Sven Eckelmann 
Signed-off-by: Simon Wunderlich

batman-adv: Only read OGM tvlv_len after buffer len check

2019-08-23T16:20:17+00:00

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 
Acked-by: Antonio Quartulli 
Signed-off-by: Simon Wunderlich

batman-adv: fix uninit-value in batadv_netlink_get_ifindex()

2019-08-14T17:27:07+00:00

batadv_netlink_get_ifindex() needs to make sure user passed
a correct u32 attribute.

syzbot reported :
BUG: KMSAN: uninit-value in batadv_netlink_dump_hardif+0x70d/0x880 net/batman-adv/netlink.c:968
CPU: 1 PID: 11705 Comm: syz-executor888 Not tainted 5.1.0+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x191/0x1f0 lib/dump_stack.c:113
 kmsan_report+0x130/0x2a0 mm/kmsan/kmsan.c:622
 __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:310
 batadv_netlink_dump_hardif+0x70d/0x880 net/batman-adv/netlink.c:968
 genl_lock_dumpit+0xc6/0x130 net/netlink/genetlink.c:482
 netlink_dump+0xa84/0x1ab0 net/netlink/af_netlink.c:2253
 __netlink_dump_start+0xa3a/0xb30 net/netlink/af_netlink.c:2361
 genl_family_rcv_msg net/netlink/genetlink.c:550 [inline]
 genl_rcv_msg+0xfc1/0x1a40 net/netlink/genetlink.c:627
 netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2486
 genl_rcv+0x63/0x80 net/netlink/genetlink.c:638
 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
 netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1337
 netlink_sendmsg+0x127e/0x12f0 net/netlink/af_netlink.c:1926
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:661 [inline]
 ___sys_sendmsg+0xcc6/0x1200 net/socket.c:2260
 __sys_sendmsg net/socket.c:2298 [inline]
 __do_sys_sendmsg net/socket.c:2307 [inline]
 __se_sys_sendmsg+0x305/0x460 net/socket.c:2305
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2305
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x440209

Fixes: b60620cf567b ("batman-adv: netlink: hardif query")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Signed-off-by: Sven Eckelmann 
Signed-off-by: Simon Wunderlich

batman-adv: Fix deletion of RTR(4|6) mcast list entries

2019-07-22T19:34:58+00:00

The multicast code uses the lists bat_priv->mcast.want_all_rtr*_list to
store all all originator nodes which don't have the flag no-RTR4 or no-RTR6
set. When an originator is purged, it has to be removed from these lists.

Since all entries without the BATADV_MCAST_WANT_NO_RTR4/6 are stored in
these lists, they have to be handled like entries which have these flags
set to force the update routines to remove them from the lists when purging
the originator.

Not doing so will leave a pointer to a freed memory region inside the list.
Trying to operate on these lists will then cause an use-after-free error:

  BUG: KASAN: use-after-free in batadv_mcast_want_rtr4_update+0x335/0x3a0 [batman_adv]
  Write of size 8 at addr ffff888007b41a38 by task swapper/0/0

Fixes: 61caf3d109f5 ("batman-adv: mcast: detect, distribute and maintain multicast router presence")
Signed-off-by: Sven Eckelmann 
Acked-by: Linus Lüssing 
Signed-off-by: Simon Wunderlich

batman-adv: Fix netlink dumping of all mcast_flags buckets

2019-07-22T19:34:58+00:00

The bucket variable is only updated outside the loop over the mcast_flags
buckets. It will only be updated during a dumping run when the dumping has
to be interrupted and a new message has to be started.

This could result in repeated or missing entries when the multicast flags
are dumped to userspace.

Fixes: d2d489b7d851 ("batman-adv: Add inconsistent multicast netlink dump detection")
Signed-off-by: Sven Eckelmann 
Signed-off-by: Simon Wunderlich

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2019-07-09T02:48:57+00:00

Two cases of overlapping changes, nothing fancy.

Signed-off-by: David S. Miller

batman-adv: mcast: apply optimizations for routable packets, too

2019-06-27T17:25:05+00:00

Now that we not only track the presence of multicast listeners but also
multicast routers we can safely apply group-aware multicast-to-unicast
forwarding to packets with a destination address of scope greater than
link-local as well.

Signed-off-by: Linus Lüssing 
Signed-off-by: Sven Eckelmann 
Signed-off-by: Simon Wunderlich

batman-adv: mcast: detect, distribute and maintain multicast router presence

2019-06-27T17:25:05+00:00

To be able to apply our group aware multicast optimizations to packets
with a scope greater than link-local we need to not only keep track of
multicast listeners but also multicast routers.

With this patch a node detects the presence of multicast routers on
its segment by checking if
/proc/sys/net/ipv{4,6}/conf//mc_forwarding is set for one
thing. This option is enabled by multicast routing daemons and needed
for the kernel's multicast routing tables to receive and route packets.

For another thing if a bridge is configured on top of bat0 then the
presence of an IPv6 multicast router behind this bridge is currently
detected by checking for an IPv6 multicast "All Routers Address"
(ff02::2). This should later be replaced by querying the bridge, which
performs proper, RFC4286 compliant Multicast Router Discovery (our
simplified approach includes more hosts than necessary, most notably
not just multicast routers but also unicast ones and is not applicable
for IPv4).

If no multicast router is detected then this is signalized via the new
BATADV_MCAST_WANT_NO_RTR4 and BATADV_MCAST_WANT_NO_RTR6
multicast tvlv flags.

Signed-off-by: Linus Lüssing 
Signed-off-by: Sven Eckelmann 
Signed-off-by: Simon Wunderlich

batman-adv: no need to check return value of debugfs_create functions

2019-06-27T17:25:04+00:00

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Because we don't care if debugfs works or not, this trickles back a bit
so we can clean things up by making some functions return void instead
of an error value that is never going to fail.

Cc: Marek Lindner 
Cc: Simon Wunderlich 
Cc: Antonio Quartulli 
Cc: "David S. Miller" 
Cc: b.a.t.m.a.n@lists.open-mesh.org
Cc: netdev@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman 
[sven@narfation.org: drop unused variables]
Signed-off-by: Sven Eckelmann 
Signed-off-by: Simon Wunderlich

batman-adv: mcast: avoid redundant multicast TT entries with bridges

2019-06-27T17:25:04+00:00

When a bridge is added on top of bat0 we set the WANT_ALL_UNSNOOPABLES
flag. Which means we sign up for all traffic for ff02::1/128 and
224.0.0.0/24.

When the node itself had IPv6 enabled or joined a group in 224.0.0.0/24
itself then so far this would result in a multicast TT entry which is
redundant to the WANT_ALL_UNSNOOPABLES.

With this patch such redundant TT entries are avoided.

Signed-off-by: Linus Lüssing 
Signed-off-by: Sven Eckelmann 
Signed-off-by: Simon Wunderlich