[ Upstream commit f2f7358c3890e7366cbcb7512b4bc8b4394b2d61 ]
The number of TT changes can be less than initially expected in
batadv_tt_tvlv_container_update() (changes can be removed by
batadv_tt_local_event() in ADD+DEL sequence between reading
tt_diff_entries_num and actually iterating the change list under lock).
Thus tt_diff_len could be bigger than the actual changes size that need
to be sent. Because batadv_send_my_tt_response sends the whole
packet, uninitialized data can be interpreted as TT changes on other
nodes leading to weird TT global entries on those nodes such as:
* 00:00:00:00:00:00 -1 [....] ( 0) 88:12:4e:ad:7e:ba (179) (0x45845380)
* 00:00:00:00:78:79 4092 [.W..] ( 0) 88:12:4e:ad:7e:3c (145) (0x8ebadb8b)
All of the above also applies to OGM tvlv container buffer's tvlv_len.
Remove the extra allocated space to avoid sending uninitialized TT
changes in batadv_send_my_tt_response() and batadv_v_ogm_send_softif().
Fixes: e1bf0c14096f ("batman-adv: tvlv - convert tt data sent within OGMs")
Signed-off-by: Remi Pommarel <repk@triplefau.lt>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>