Jason A. Donenfeld bf7b042dc6 wireguard: allowedips: free empty intermediate nodes when removing single node ... When removing single nodes, it's possible that that node's parent is an empty intermediate node, in which case, it too should be removed. Otherwise the trie fills up and never is fully emptied, leading to gradual memory leaks over time for tries that are modified often. There was originally code to do this, but was removed during refactoring in 2016 and never reworked. Now that we have proper parent pointers from the previous commits, we can implement this properly. In order to reduce branching and expensive comparisons, we want to keep the double pointer for parent assignment (which lets us easily chain up to the root), but we still need to actually get the parent's base address. So encode the bit number into the last two bits of the pointer, and pack and unpack it as needed. This is a little bit clumsy but is the fastest and less memory wasteful of the compromises. Note that we align the root struct here to a minimum of 4, because it's embedded into a larger struct, and we're relying on having the bottom two bits for our flag, which would only be 16-bit aligned on m68k. The existing macro-based helpers were a bit unwieldy for adding the bit packing to, so this commit replaces them with safer and clearer ordinary functions. We add a test to the randomized/fuzzer part of the selftests, to free the randomized tries by-peer, refuzz it, and repeat, until it's supposed to be empty, and then then see if that actually resulted in the whole thing being emptied. That combined with kmemcheck should hopefully make sure this commit is doing what it should. Along the way this resulted in various other cleanups of the tests and fixes for recent graphviz. Fixes: e7096c131e ("net: WireGuard secure network tunnel") Cc: stable@vger.kernel.org Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2021-06-04 14:25:14 -07:00
..
selftest	wireguard: allowedips: free empty intermediate nodes when removing single node	2021-06-04 14:25:14 -07:00
allowedips.c	wireguard: allowedips: free empty intermediate nodes when removing single node	2021-06-04 14:25:14 -07:00
allowedips.h	wireguard: allowedips: free empty intermediate nodes when removing single node	2021-06-04 14:25:14 -07:00
cookie.c
cookie.h
device.c	wireguard: queueing: get rid of per-peer ring buffers	2021-02-23 15:59:34 -08:00
device.h	wireguard: queueing: get rid of per-peer ring buffers	2021-02-23 15:59:34 -08:00
main.c	wireguard: allowedips: allocate nodes in kmem_cache	2021-06-04 14:25:14 -07:00
Makefile	wireguard: do not use -O3	2021-06-04 14:25:14 -07:00
messages.h	wireguard: queueing: preserve flow hash across packet scrubbing	2020-05-20 20:55:09 -07:00
netlink.c	netlink: consistently use NLA_POLICY_MIN_LEN()	2020-08-18 12:28:45 -07:00
netlink.h
noise.c	wireguard: noise: take lock when removing handshake entry from table	2020-09-09 11:31:37 -07:00
noise.h	wireguard: noise: separate receive counter from send counter	2020-05-20 20:55:09 -07:00
peer.c	wireguard: peer: allocate in kmem_cache	2021-06-04 14:25:14 -07:00
peer.h	wireguard: peer: allocate in kmem_cache	2021-06-04 14:25:14 -07:00
peerlookup.c	wireguard: peerlookup: take lock before checking hash in replace operation	2020-09-09 11:31:38 -07:00
peerlookup.h
queueing.c	wireguard: queueing: get rid of per-peer ring buffers	2021-02-23 15:59:34 -08:00
queueing.h	wireguard: queueing: get rid of per-peer ring buffers	2021-02-23 15:59:34 -08:00
ratelimiter.c
ratelimiter.h
receive.c	wireguard: queueing: get rid of per-peer ring buffers	2021-02-23 15:59:34 -08:00
send.c	wireguard: queueing: get rid of per-peer ring buffers	2021-02-23 15:59:34 -08:00
socket.c	wireguard: use synchronize_net rather than synchronize_rcu	2021-06-04 14:25:14 -07:00
socket.h
timers.c
timers.h
version.h