Pablo Neira Ayuso says:

====================
Netfilter/IPVS fixes for net

The following patchset contains Netfilter/IPVS fixes for your net tree,
they are:

1) Don't truncate ethernet protocol type to u8 in nft_compat, from
   Arturo Borrero.

2) Fix several problems in the addition/deletion of elements in nf_tables.

3) Fix module refcount leak in ip_vs_sync, from Julian Anastasov.

4) Fix a race condition in the abort path in the nf_tables transaction
   infrastructure. Basically aborted rules can show up as active rules
   until changes are unrolled, oneliner from Patrick McHardy.

5) Check for overflows in the data area of the rule, also from Patrick.

6) Fix off-by-one in the per-rule user data size field. This introduces
   a new nft_userdata structure that is placed at the beginning of the
   user data area that contains the length to save some bits from the
   rule and we only need one bit to indicate its presence, from Patrick.

7) Fix rule replacement error path, the replaced rule is deleted on
   error instead of leaving it in place. This has been fixed by relying
   on the abort path to undo the incomplete replacement.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

In general, if a transaction object is added to the list successfully,
we can rely on the abort path to undo what we've done. This allows us to
simplify the error handling of the rule replacement path in
nf_tables_newrule().

This implicitly fixes an unnecessary removal of the old rule, which
needs to be left in place if we fail to replace.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

The NFT_USERDATA_MAXLEN is defined to 256, however we only have a u8
to store its size. Introduce a struct nft_userdata which contains a
length field and indicate its presence using a single bit in the rule.

The length field of struct nft_userdata is also a u8, however we don't
store zero sized data, so the actual length is udata->len + 1.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Check that the space required for the expressions doesn't exceed the
size of the dlen field, which would lead to the iterators crashing.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

A race condition exists in the rule transaction code for rules that
get added and removed within the same transaction.

The new rule starts out as inactive in the current and active in the
next generation and is inserted into the ruleset. When it is deleted,
it is additionally set to inactive in the next generation as well.

On commit the next generation is begun, then the actions are finalized.
For the new rule this would mean clearing out the inactive bit for
the previously current, now next generation.

However nft_rule_clear() clears out the bits for *both* generations,
activating the rule in the current generation, where it should be
deactivated due to being deleted. The rule will thus be active until
the deletion is finalized, removing the rule from the ruleset.

Similarly, when aborting a transaction for the same case, the undo
of insertion will remove it from the RCU protected rule list, the
deletion will clear out all bits. However until the next RCU
synchronization after all operations have been undone, the rule is
active on CPUs which can still see the rule on the list.

Generally, there may never be any modifications of the current
generations' inactive bit since this defeats the entire purpose of
atomicity. Change nft_rule_clear() to only touch the next generations
bit to fix this.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Currently, all real users of rhashtable default their grow and shrink
decision functions to rht_grow_above_75() and rht_shrink_below_30(),
so that there's currently no need to have this explicitly selectable.

It can/should be generic and private inside rhashtable until a real
use case pops up. Since we can make this private, we'll save us this
additional indirection layer and can improve insertion/deletion time
as well.

Reference: http://patchwork.ozlabs.org/patch/443040/
Suggested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Simon Horman says:

====================
Second Round of IPVS Fixes for v3.20

This patch resolves some memory leaks in connection
synchronisation code that date back to v2.6.39.
====================

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

ip_vs_conn_fill_param_sync() gets in param.pe a module
reference for persistence engine from __ip_vs_pe_getbyname()
but forgets to put it. Problem occurs in backup for
sync protocol v1 (2.6.39).

Also, pe_data usually comes in sync messages for
connection templates and ip_vs_conn_new() copies
the pointer only in this case. Make sure pe_data
is not leaked if it comes unexpectedly for normal
connections. Leak can happen only if bogus messages
are sent to backup server.

Fixes: fe5e7a1efb66 ("IPVS: Backup, Adding Version 1 receive capability")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>

We have several problems in this path:

1) There is a use-after-free when removing individual elements from
   the commit path.

2) We have to uninit() the data part of the element from the abort
   path to avoid a chain refcount leak.

3) We have to check for set->flags to see if there's a mapping, instead
   of the element flags.

4) We have to check for !(flags & NFT_SET_ELEM_INTERVAL_END) to skip
   elements that are part of the interval that have no data part, so
   they don't need to be uninit().

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Use u16 for protocol and then cast it to __be16

>> net/netfilter/nft_compat.c:140:37: sparse: incorrect type in assignment (different base types)
   net/netfilter/nft_compat.c:140:37:    expected restricted __be16 [usertype] ethproto
   net/netfilter/nft_compat.c:140:37:    got unsigned char [unsigned] [usertype] proto
>> net/netfilter/nft_compat.c:351:37: sparse: incorrect type in assignment (different base types)
   net/netfilter/nft_compat.c:351:37:    expected restricted __be16 [usertype] ethproto
   net/netfilter/nft_compat.c:351:37:    got unsigned char [unsigned] [usertype] proto

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>