totalram_pages and totalhigh_pages are made static inline function.
Main motivation was that managed_page_count_lock handling was complicating
things. It was discussed in length here,
https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes
better to remove the lock and convert variables to atomic, with preventing
poteintial store-to-read tearing as a bonus.
[akpm@linux-foundation.org: coding style fixes]
Link: http://lkml.kernel.org/r/1542090790-21750-4-git-send-email-arunks@codeaurora.org
Signed-off-by: Arun KS <arunks@codeaurora.org>
Suggested-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm: convert totalram_pages, totalhigh_pages and managed
pages to atomic", v5.
This series converts totalram_pages, totalhigh_pages and
zone->managed_pages to atomic variables.
totalram_pages, zone->managed_pages and totalhigh_pages updates are
protected by managed_page_count_lock, but readers never care about it.
Convert these variables to atomic to avoid readers potentially seeing a
store tear.
Main motivation was that managed_page_count_lock handling was complicating
things. It was discussed in length here,
https://lore.kernel.org/patchwork/patch/995739/#1181785 It seemes better
to remove the lock and convert variables to atomic. With the change,
preventing poteintial store-to-read tearing comes as a bonus.
This patch (of 4):
This is in preparation to a later patch which converts totalram_pages and
zone->managed_pages to atomic variables. Please note that re-reading the
value might lead to a different value and as such it could lead to
unexpected behavior. There are no known bugs as a result of the current
code but it is better to prevent from them in principle.
Link: http://lkml.kernel.org/r/1542090790-21750-2-git-send-email-arunks@codeaurora.org
Signed-off-by: Arun KS <arunks@codeaurora.org>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains Netfilter updates for net-next:
1) Support for destination MAC in ipset, from Stefano Brivio.
2) Disallow all-zeroes MAC address in ipset, also from Stefano.
3) Add IPSET_CMD_GET_BYNAME and IPSET_CMD_GET_BYINDEX commands,
introduce protocol version number 7, from Jozsef Kadlecsik.
A follow up patch to fix ip_set_byindex() is also included
in this batch.
4) Honor CTA_MARK_MASK from ctnetlink, from Andreas Jaggi.
5) Statify nf_flow_table_iterate(), from Taehee Yoo.
6) Use nf_flow_table_iterate() to simplify garbage collection in
nf_flow_table logic, also from Taehee Yoo.
7) Don't use _bh variants of call_rcu(), rcu_barrier() and
synchronize_rcu_bh() in Netfilter, from Paul E. McKenney.
8) Remove NFC_* cache definition from the old caching
infrastructure.
9) Remove layer 4 port rover in NAT helpers, use random port
instead, from Florian Westphal.
10) Use strscpy() in ipset, from Qian Cai.
11) Remove NF_NAT_RANGE_PROTO_RANDOM_FULLY branch now that
random port is allocated by default, from Xiaozhou Liu.
12) Ignore NF_NAT_RANGE_PROTO_RANDOM too, from Florian Westphal.
13) Limit port allocation selection routine in NAT to avoid
softlockup splats when most ports are in use, from Florian.
14) Remove unused parameters in nf_ct_l4proto_unregister_sysctl()
from Yafang Shao.
15) Direct call to nf_nat_l4proto_unique_tuple() instead of
indirection, from Florian Westphal.
16) Several patches to remove all layer 4 NAT indirections,
remove nf_nat_l4proto struct, from Florian Westphal.
17) Fix RTP/RTCP source port translation when SNAT is in place,
from Alin Nastac.
18) Selective rule dump per chain, from Phil Sutter.
19) Revisit CLUSTERIP target, this includes a deadlock fix from
netns path, sleep in atomic, remove bogus WARN_ON_ONCE()
and disallow mismatching IP address and MAC address.
Patchset from Taehee Yoo.
20) Update UDP timeout to stream after 2 seconds, from Florian.
21) Shrink UDP established timeout to 120 seconds like TCP timewait.
22) Sysctl knobs to set GRE timeouts, from Yafang Shao.
23) Move seq_print_acct() to conntrack core file, from Florian.
24) Add enum for conntrack sysctl knobs, also from Florian.
25) Place nf_conntrack_acct, nf_conntrack_helper, nf_conntrack_events
and nf_conntrack_timestamp knobs in the core, from Florian Westphal.
As a side effect, shrink netns_ct structure by removing obsolete
sysctl anchors, also from Florian.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
after moving sysctl handling into single place, the init functions
can't fail anymore and some of the fini functions are empty.
Remove them and change return type to void.
This also simplifies error unwinding in conntrack module init path.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Similar to previous change, this time for eache and timestamp.
Unlike helper and acct, these can be disabled at build time, so they
need ifdef guards.
Next patch will remove a few (now obsolete) functions.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Needless copy&paste, just handle all in one. Next patch will handle
acct and timestamp, which have similar functions.
Intentionally leaves cruft behind, will be cleaned up in a followup
patch.
The obsolete sysctl pointers in netns_ct struct are left in place and
removed in a single change, as changes to netns trigger rebuild of
almost all files.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Its a bit hard to see what table[3] really lines up with, so add
human-readable mnemonics and use them for initialisation.
This makes it easier to see e.g. which sysctls are not exported to
unprivileged userns.
objdiff shows no changes.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds two sysctl knobs for GRE:
net.netfilter.nf_conntrack_gre_timeout = 30
net.netfilter.nf_conntrack_gre_timeout_stream = 180
Update the Documentation as well.
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We have no explicit signal when a UDP stream has terminated, peers just
stop sending.
For suspected stream connections a timeout of two minutes is sane to keep
NAT mapping alive a while longer.
It matches tcp conntracks 'timewait' default timeout value.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently DNS resolvers that send both A and AAAA queries from same source port
can trigger stream mode prematurely, which results in non-early-evictable conntrack entry
for three minutes, even though DNS requests are done in a few milliseconds.
Add a two second grace period where we continue to use the ordinary
30-second default timeout. Its enough for DNS request/response traffic,
even if two request/reply packets are involved.
ASSURED is still set, else conntrack (and thus a possible
NAT mapping ...) gets zapped too in case conntrack table runs full.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Lots of conflicts, by happily all cases of overlapping
changes, parallel adds, things of that nature.
Thanks to Stephen Rothwell, Saeed Mahameed, and others
for their guidance in these resolutions.
Signed-off-by: David S. Miller <davem@davemloft.net>
skb_sec_path gains 'const' qualifier to avoid
xt_policy.c: 'skb_sec_path' discards 'const' qualifier from pointer target type
same reasoning as previous conversions: Won't need to touch these
spots anymore when skb->sp is removed.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Future patch will remove skb->sp pointer.
To reduce noise in those patches, move existing helper to
sk_buff and use it in more places to ease skb->sp replacement later.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This pointer is going to be removed soon, so use the existing helpers in
more places to avoid noise when the removal happens.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
If just a table name was given, nf_tables_dump_rules() continued over
the list of tables even after a match was found. The simple fix is to
exit the loop if it reached the bottom and ctx->table was not NULL.
When iterating over the table's chains, the same problem as above
existed. But worse than that, if a chain name was given the hash table
wasn't used to find the corresponding chain. Fix this by introducing a
helper function iterating over a chain's rules (and taking care of the
cb->args handling), then introduce a shortcut to it if a chain name was
given.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Each media stream negotiation between 2 SIP peers will trigger creation
of 4 different expectations (2 RTP and 2 RTCP):
- INVITE will create expectations for the media packets sent by the
called peer
- reply to the INVITE will create expectations for media packets sent
by the caller
The dport used by these expectations usually match the ones selected
by the SIP peers, but they might get translated due to conflicts with
another expectation. When such event occur, it is important to do
this translation in both directions, dport translation on the receiving
path and sport translation on the sending path.
This commit fixes the sport translation when the peer requiring it is
also the one that starts the media stream. In this scenario, first media
stream packet is forwarded from LAN to WAN and will rely on
nf_nat_sip_expected() to do the necessary sport translation. However, the
expectation matched by this packet does not contain the necessary information
for doing SNAT, this data being stored in the paired expectation created by
the sender's SIP message (INVITE or reply to it).
Signed-off-by: Alin Nastac <alin.nastac@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This removes the (now empty) nf_nat_l4proto struct, all its instances
and all the no longer needed runtime (un)register functionality.
nf_nat_need_gre() can be axed as well: the module that calls it (to
load the no-longer-existing nat_gre module) also calls other nat core
functions. GRE nat is now always available if kernel is built with it.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This removes the last l4proto indirection, the two callers, the l3proto
packet mangling helpers for ipv4 and ipv6, now call the
nf_nat_l4proto_manip_pkt() helper.
nf_nat_proto_{dccp,tcp,sctp,gre,icmp,icmpv6} are left behind, even though
they contain no functionality anymore to not clutter this patch.
Next patch will remove the empty files and the nf_nat_l4proto
struct.
nf_nat_proto_udp.c is renamed to nf_nat_proto.c, as it now contains the
other nat manip functionality as well, not just udp and udplite.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
all protocols did set this to nf_nat_l4proto_nlattr_to_range, so
just call it directly.
The important difference is that we'll now also call it for
protocols that we don't support (i.e., nf_nat_proto_unknown did
not provide .nlattr_to_range).
However, there should be no harm, even icmp provided this callback.
If we don't implement a specific l4nat for this, nothing would make
use of this information, so adding a big switch/case construct listing
all supported l4protocols seems a bit pointless.
This change leaves a single function pointer in the l4proto struct.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
With exception of icmp, all of the l4 nat protocols set this to
nf_nat_l4proto_in_range.
Get rid of this and just check the l4proto in the caller.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
No need for indirections here, we only support ipv4 and ipv6
and the called functions are very small.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
fold remaining users (icmp, icmpv6, gre) into nf_nat_l4proto_unique_tuple.
The static-save of old incarnation of resolved key in gre and icmp is
removed as well, just use the prandom based offset like the others.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
almost all l4proto->unique_tuple implementations just call this helper,
so make ->unique_tuple() optional and call its helper directly if the
l4proto doesn't override it.
This is an intermediate step to get rid of ->unique_tuple completely.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Historically this was net_random() based, and was then converted to
a hash based algorithm (private boot seed + hash of endpoint addresses)
due to concerns of leaking net_random() bits.
RANDOM_FULLY mode was added later to avoid problems with hash
based mode (see commit 34ce324019,
"netfilter: nf_nat: add full port randomization support" for details).
Just make prandom_u32() the default search starting point and get rid of
->secure_port() altogether.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In case almost or all available ports are taken, clash resolution can
take a very long time, resulting in soft lockup.
This can happen when many to-be-natted hosts connect to same
destination:port (e.g. a proxy) and all connections pass the same SNAT.
Pick a random offset in the acceptable range, then try ever smaller
number of adjacent port numbers, until either the limit is reached or a
useable port was found. This results in at most 248 attempts
(128 + 64 + 32 + 16 + 8, i.e. 4 restarts with new search offset)
instead of 64000+,
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Since a pseudo-random starting point is used in finding a port in
the default case, that 'else if' branch above is no longer a necessity.
So remove it to simplify code.
Signed-off-by: Xiaozhou Liu <liuxiaozhou@bytedance.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
To make overflows as obvious as possible and to prevent code from blithely
proceeding with a truncated string. This also has a side-effect to fix a
compilation warning when using GCC 8.2.1.
net/netfilter/ipset/ip_set_core.c: In function 'ip_set_sockfn_get':
net/netfilter/ipset/ip_set_core.c:2027:3: warning: 'strncpy' writing 32 bytes into a region of size 2 overflows the destination [-Wstringop-overflow=]
Signed-off-by: Qian Cai <cai@gmx.us>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
New function added by "Introduction of new commands and protocol
version 7" is not working, since we return skb2 to user
Signed-off-by: Victorien Molle <victorien.molle@wifirst.fr>
Signed-off-by: Florent Fourcot <florent.fourcot@wifirst.fr>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
rbnode in insert_tree() is rcu protected pointer.
So, in order to handle this pointer, _rcu function should be used.
rb_link_node_rcu() is a rcu version of rb_link_node().
Fixes: 34848d5c89 ("netfilter: nf_conncount: Split insert and traversal")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In the error handling block, nla_nest_cancel(skb, atd) is called to
cancel the nest operation. But then, ipset_nest_end(skb, atd) is
unexpected called to end the nest operation. This patch calls the
ipset_nest_end only on the branch that nla_nest_cancel is not called.
Fixes: 45040978c8 ("netfilter: ipset: Fix set:list type crash when flush/dump set in parallel")
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When adjusting sack block sequence numbers, skb_make_writable() gets
called to make sure tcp options are all in the linear area, and buffer
is not shared.
This can cause tcp header pointer to get reallocated, so we must
reaload it to avoid memory corruption.
This bug pre-dates git history.
Reported-by: Neel Mehta <nmehta@google.com>
Reported-by: Shane Huntley <shuntley@google.com>
Reported-by: Heather Adkins <argv@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This is a leftover from days where single-cpu systems were common:
Store last port used to resolve a clash to use it as a starting point when
the next conflict needs to be resolved.
When we have parallel attempt to connect to same address:port pair,
its likely that both cores end up computing the same "available" port,
as both use same starting port, and newly used ports won't become
visible to other cores until the conntrack gets confirmed later.
One of the cores then has to drop the packet at insertion time because
the chosen new tuple turns out to be in use after all.
Lets simplify this: remove port rover and use a pseudo-random starting
point.
Note that this doesn't make netfilter default to 'fully random' mode;
the 'rover' was only used if NAT could not reuse source port as-is.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Now that call_rcu()'s callback is not invoked until after bh-disable
regions of code have completed (in addition to explicitly marked
RCU read-side critical sections), call_rcu() can be used in place
of call_rcu_bh(). Similarly, rcu_barrier() can be used in place of
rcu_barrier_bh() and synchronize_rcu() in place of synchronize_rcu_bh().
This commit therefore makes these changes.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Trivial conflict in net/core/filter.c, a locally computed
'sdif' is now an argument to the function.
Signed-off-by: David S. Miller <davem@davemloft.net>
All lists that reach the tree_nodes_free() function have both zero
counter and true dead flag. The reason for this is that lists to be
release are selected by nf_conncount_gc_list() which already decrements
the list counter and sets on the dead flag. Therefore, this if statement
in tree_nodes_free() is unnecessary and wrong.
Fixes: 31568ec09e ("netfilter: nf_conncount: fix list_del corruption in conn_free")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
register_{netdevice/inetaddr/inet6addr}_notifier may return an error
value, this patch adds the code to handle these error paths.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
syzbot was able to trigger the WARN in cttimeout_default_get() by
passing UDPLITE as l4protocol. Alias UDPLITE to UDP, both use
same timeout values.
Furthermore, also fetch GRE timeouts. GRE is a bit more complicated,
as it still can be a module and its netns_proto_gre struct layout isn't
visible outside of the gre module. Can't move timeouts around, it
appears conntrack sysctl unregister assumes net_generic() returns
nf_proto_net, so we get crash. Expose layout of netns_proto_gre instead.
A followup nf-next patch could make gre tracker be built-in as well
if needed, its not that large.
Last, make the WARN() mention the missing protocol value in case
anything else is missing.
Reported-by: syzbot+2fae8fa157dd92618cae@syzkaller.appspotmail.com
Fixes: 8866df9264 ("netfilter: nfnetlink_cttimeout: pass default timeout policy to obj_to_nlattr")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
ip_vs_dst_event is supposed to clean up all dst used in ipvs'
destinations when a net dev is going down. But it works only
when the dst's dev is the same as the dev from the event.
Now with the same priority but late registration,
ip_vs_dst_notifier is always called later than ipv6_dev_notf
where the dst's dev is set to lo for NETDEV_DOWN event.
As the dst's dev lo is not the same as the dev from the event
in ip_vs_dst_event, ip_vs_dst_notifier doesn't actually work.
Also as these dst have to wait for dest_trash_timer to clean
them up. It would cause some non-permanent kernel warnings:
unregister_netdevice: waiting for br0 to become free. Usage count = 3
To fix it, call ip_vs_dst_notifier earlier than ipv6_dev_notf
by increasing its priority to ADDRCONF_NOTIFY_PRIORITY + 5.
Note that for ipv4 route fib_netdev_notifier doesn't set dst's
dev to lo in NETDEV_DOWN event, so this fix is only needed when
IP_VS_IPV6 is defined.
Fixes: 7a4f0761fc ("IPVS: init and cleanup restructuring")
Reported-by: Li Shuang <shuali@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In the htable_create(), hinfo is allocated by vmalloc()
So that if error occurred, hinfo should be freed.
Fixes: 11d5f15723 ("netfilter: xt_hashlimit: Create revision 2 to support higher pps rates")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nft_compat ops do not have static storage duration, unlike all other
expressions.
When nf_tables_expr_destroy() returns, expr->ops might have been
free'd already, so we need to store next address before calling
expression destructor.
For same reason, we can't deref match pointer after nft_xt_put().
This can be easily reproduced by adding msleep() before
nft_match_destroy() returns.
Fixes: 0ca743a559 ("netfilter: nf_tables: add compatibility layer for x_tables")
Reported-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_flow_offload_gc_step() and nf_flow_table_iterate() are very similar.
so that many duplicate code can be removed.
After this patch, nf_flow_offload_gc_step() is simple callback function of
nf_flow_table_iterate() like nf_flow_table_do_cleanup().
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_flow_table_iterate() is local function, make it static.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Its possible to set both HANDLE and POSITION when replacing a rule.
In this case, the rule at POSITION gets replaced using the
userspace-provided handle. Rule handles are supposed to be generated
by the kernel only.
Duplicate handles should be harmless, however better disable this "feature"
by only checking for the POSITION attribute on insert operations.
Fixes: 5e94846686 ("netfilter: nf_tables: add insert operation")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There is no synchronization between packet path and the configuration plane.
The packet path uses two arrays with rules, one contains the current (active)
generation. The other either contains the last (obsolete) generation or
the future one.
Consider:
cpu1 cpu2
nft_do_chain(c);
delete c
net->gen++;
genbit = !!net->gen;
rules = c->rg[genbit];
cpu1 ignores c when updating if c is not active anymore in the new
generation.
On cpu2, we now use rules from wrong generation, as c->rg[old]
contains the rules matching 'c' whereas c->rg[new] was not updated and
can even point to rules that have been free'd already, causing a crash.
To fix this, make sure that 'current' to the 'next' generation are
identical for chains that are going away so that c->rg[new] will just
use the matching rules even if genbit was incremented already.
Fixes: 0cbc06b3fa ("netfilter: nf_tables: remove synchronize_rcu in commit phase")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
