linux.git/net/netfilter, branch v6.0-rc2

netfilter: conntrack: NF_CONNTRACK_PROCFS should no longer default to y

2022-08-17T06:46:30+00:00

NF_CONNTRACK_PROCFS was marked obsolete in commit 54b07dca68557b09
("netfilter: provide config option to disable ancient procfs parts") in
v3.3.

Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Florian Westphal

netfilter: nf_tables: check NFT_SET_CONCAT flag if field_count is specified

2022-08-15T16:41:21+00:00

Since f3a2181e16f1 ("netfilter: nf_tables: Support for sets with
multiple ranged fields"), it possible to combine intervals and
concatenations. Later on, ef516e8625dd ("netfilter: nf_tables:
reintroduce the NFT_SET_CONCAT flag") provides the NFT_SET_CONCAT flag
for userspace to report that the set stores a concatenation.

Make sure NFT_SET_CONCAT is set on if field_count is specified for
consistency. Otherwise, if NFT_SET_CONCAT is specified with no
field_count, bail out with EINVAL.

Fixes: ef516e8625dd ("netfilter: nf_tables: reintroduce the NFT_SET_CONCAT flag")
Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: disallow NFT_SET_ELEM_CATCHALL and NFT_SET_ELEM_INTERVAL_END

2022-08-15T15:54:59+00:00

These flags are mutually exclusive, report EINVAL in this case.

Fixes: aaa31047a6d2 ("netfilter: nftables: add catch-all set element support")
Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: NFTA_SET_ELEM_KEY_END requires concat and interval flags

2022-08-15T15:54:51+00:00

If the NFT_SET_CONCAT|NFT_SET_INTERVAL flags are set on, then the
netlink attribute NFTA_SET_ELEM_KEY_END must be specified. Otherwise,
NFTA_SET_ELEM_KEY_END should not be present.

For catch-all element, NFTA_SET_ELEM_KEY_END should not be present.
The NFT_SET_ELEM_INTERVAL_END is never used with this set flags
combination.

Fixes: 7b225d0b5c6d ("netfilter: nf_tables: add NFTA_SET_ELEM_KEY_END attribute")
Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: validate NFTA_SET_ELEM_OBJREF based on NFT_SET_OBJECT flag

2022-08-12T14:32:16+00:00

If the NFTA_SET_ELEM_OBJREF netlink attribute is present and
NFT_SET_OBJECT flag is set on, report EINVAL.

Move existing sanity check earlier to validate that NFT_SET_OBJECT
requires NFTA_SET_ELEM_OBJREF.

Fixes: 8aeff920dcc9 ("netfilter: nf_tables: add stateful object reference to set elements")
Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: really skip inactive sets when allocating name

2022-08-11T16:53:48+00:00

While looping to build the bitmap of used anonymous set names, check the
current set in the iteration, instead of the one that is being created.

Fixes: 37a9cc525525 ("netfilter: nf_tables: add generation mask to sets")
Signed-off-by: Pablo Neira Ayuso

netfilter: nfnetlink: re-enable conntrack expectation events

2022-08-11T16:09:54+00:00

To avoid allocation of the conntrack extension area when possible,
the default behaviour was changed to only allocate the event extension
if a userspace program is subscribed to a notification group.

Problem is that while 'conntrack -E' does enable the event allocation
behind the scenes, 'conntrack -E expect' does not: no expectation events
are delivered unless user sets
"net.netfilter.nf_conntrack_events" back to 1 (always on).

Fix the autodetection to also consider EXP type group.

We need to track the 6 event groups (3+3, new/update/destroy for events and
for expectations each) independently, else we'd disable events again
if an expectation group becomes empty while there is still an active
event group.

Fixes: 2794cdb0b97b ("netfilter: nfnetlink: allow to detect if ctnetlink listeners exist")
Reported-by: Yi Chen 
Signed-off-by: Florian Westphal

netfilter: nf_tables: fix scheduling-while-atomic splat

2022-08-11T15:57:28+00:00

nf_tables_check_loops() can be called from rhashtable list
walk so cond_resched() cannot be used here.

Fixes: 81ea01066741 ("netfilter: nf_tables: add rescheduling points during loop detection walks")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: nf_ct_irc: cap packet search space to 4k

2022-08-11T14:51:13+00:00

This uses a pseudo-linearization scheme with a 64k global buffer,
but BIG TCP arrival means IPv6 TCP stack can generate skbs
that exceed this size.

In practice, IRC commands are not expected to exceed 512 bytes, plus
this is interactive protocol, so we should not see large packets
in practice.

Given most IRC connections nowadays use TLS so this helper could also be
removed in the near future.

Fixes: 7c4e983c4f3c ("net: allow gso_max_size to exceed 65536")
Fixes: 0fe79f28bfaf ("net: allow gro_max_size to exceed 65536")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: nf_ct_ftp: prefer skb_linearize

2022-08-11T14:51:01+00:00

This uses a pseudo-linearization scheme with a 64k global buffer,
but BIG TCP arrival means IPv6 TCP stack can generate skbs
that exceed this size.

Use skb_linearize.  It should be possible to rewrite this to properly
deal with segmented skbs (i.e., only do small chunk-wise accesses),
but this is going to be a lot more intrusive than this because every
helper function needs to get the sk_buff instead of a pointer to a raw
data buffer.

In practice, provided we're really looking at FTP control channel packets,
there should never be a case where we deal with huge packets.

Fixes: 7c4e983c4f3c ("net: allow gso_max_size to exceed 65536")
Fixes: 0fe79f28bfaf ("net: allow gro_max_size to exceed 65536")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso