linux-stable.git/net/netfilter, branch v4.14.95 Linux kernel stable tree netfilter: nat: can't use dst_hold on noref dst 2019-01-13T09:00:58+00:00 Florian Westphal fw@strlen.de 2018-12-11T06:45:29+00:00 b0e56e3c569932e937fa2fa0dc5799c8f023d07e [ Upstream commit 542fbda0f08f1cbbc250f9e59f7537649651d0c8 ] The dst entry might already have a zero refcount, waiting on rcu list to be free'd. Using dst_hold() transitions its reference count to 1, and next dst release will try to free it again -- resulting in a double free: WARNING: CPU: 1 PID: 0 at include/net/dst.h:239 nf_xfrm_me_harder+0xe7/0x130 [nf_nat] RIP: 0010:nf_xfrm_me_harder+0xe7/0x130 [nf_nat] Code: 48 8b 5c 24 60 65 48 33 1c 25 28 00 00 00 75 53 48 83 c4 68 5b 5d 41 5c c3 85 c0 74 0d 8d 48 01 f0 0f b1 0a 74 86 85 c0 75 f3 <0f> 0b e9 7b ff ff ff 29 c6 31 d2 b9 20 00 48 00 4c 89 e7 e8 31 27 Call Trace: nf_nat_ipv4_out+0x78/0x90 [nf_nat_ipv4] nf_hook_slow+0x36/0xd0 ip_output+0x9f/0xd0 ip_forward+0x328/0x440 ip_rcv+0x8a/0xb0 Use dst_hold_safe instead and bail out if we cannot take a reference. Fixes: a4c2fd7f7891 ("net: remove DST_NOCACHE flag") Reported-by: Martin Zaharinov <micron10@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 542fbda0f08f1cbbc250f9e59f7537649651d0c8 ]

The dst entry might already have a zero refcount, waiting on rcu list
to be free'd.  Using dst_hold() transitions its reference count to 1, and
next dst release will try to free it again -- resulting in a double free:

  WARNING: CPU: 1 PID: 0 at include/net/dst.h:239 nf_xfrm_me_harder+0xe7/0x130 [nf_nat]
  RIP: 0010:nf_xfrm_me_harder+0xe7/0x130 [nf_nat]
  Code: 48 8b 5c 24 60 65 48 33 1c 25 28 00 00 00 75 53 48 83 c4 68 5b 5d 41 5c c3 85 c0 74 0d 8d 48 01 f0 0f b1 0a 74 86 85 c0 75 f3 <0f> 0b e9 7b ff ff ff 29 c6 31 d2 b9 20 00 48 00 4c 89 e7 e8 31 27
  Call Trace:
  nf_nat_ipv4_out+0x78/0x90 [nf_nat_ipv4]
  nf_hook_slow+0x36/0xd0
  ip_output+0x9f/0xd0
  ip_forward+0x328/0x440
  ip_rcv+0x8a/0xb0

Use dst_hold_safe instead and bail out if we cannot take a reference.

Fixes: a4c2fd7f7891 ("net: remove DST_NOCACHE flag")
Reported-by: Martin Zaharinov <micron10@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
netfilter: ipset: do not call ipset_nest_end after nla_nest_cancel 2019-01-13T09:00:58+00:00 Pan Bian bianpan2016@163.com 2018-12-10T13:39:37+00:00 e8267a5ec404913cd2fcfc51ff5e5b3671ed4916 [ Upstream commit 708abf74dd87f8640871b814faa195fb5970b0e3 ] 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: 45040978c899 ("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> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 708abf74dd87f8640871b814faa195fb5970b0e3 ]

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: 45040978c899 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
netfilter: seqadj: re-load tcp header pointer after possible head reallocation 2019-01-13T09:00:57+00:00 Florian Westphal fw@strlen.de 2018-12-05T13:12:19+00:00 5ac1f046ab4a6f629a524b9bd4f15f72bf6a4798 [ Upstream commit 530aad77010b81526586dfc09130ec875cd084e4 ] 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> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 530aad77010b81526586dfc09130ec875cd084e4 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
netfilter: nf_conncount: don't skip eviction when age is negative 2019-01-09T16:14:51+00:00 Florian Westphal fw@strlen.de 2019-01-02T20:42:04+00:00 052ccb86b31c184d8ed7d76d1c06d7ca0b8fd32e commit 4cd273bb91b3001f623f516ec726c49754571b1a upstream. (not in Linus's tree now, but in nf.git + linux-next.git already.) age is signed integer, so result can be negative when the timestamps have a large delta. In this case we want to discard the entry. Instead of using age >= 2 || age < 0, just make it unsigned. Fixes: b36e4523d4d56 ("netfilter: nf_conncount: fix garbage collection confirm race") Reviewed-by: Shawn Bohrer <sbohrer@cloudflare.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> [mfo: backport: use older file name, nf_conncount.c -> xt_connlimit.c] Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
commit 4cd273bb91b3001f623f516ec726c49754571b1a upstream.

(not in Linus's tree now, but in nf.git + linux-next.git already.)

age is signed integer, so result can be negative when the timestamps
have a large delta.  In this case we want to discard the entry.

Instead of using age >= 2 || age < 0, just make it unsigned.

Fixes: b36e4523d4d56 ("netfilter: nf_conncount: fix garbage collection confirm race")
Reviewed-by: Shawn Bohrer <sbohrer@cloudflare.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

[mfo: backport: use older file name, nf_conncount.c -> xt_connlimit.c]
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
netfilter: nf_conncount: fix garbage collection confirm race 2019-01-09T16:14:51+00:00 Florian Westphal fw@strlen.de 2019-01-02T20:42:03+00:00 75af3d78168e654a5cd8bbc4c774f97be836165f commit b36e4523d4d56e2595e28f16f6ccf1cd6a9fc452 upstream. Yi-Hung Wei and Justin Pettit found a race in the garbage collection scheme used by nf_conncount. When doing list walk, we lookup the tuple in the conntrack table. If the lookup fails we remove this tuple from our list because the conntrack entry is gone. This is the common cause, but turns out its not the only one. The list entry could have been created just before by another cpu, i.e. the conntrack entry might not yet have been inserted into the global hash. The avoid this, we introduce a timestamp and the owning cpu. If the entry appears to be stale, evict only if: 1. The current cpu is the one that added the entry, or, 2. The timestamp is older than two jiffies The second constraint allows GC to be taken over by other cpu too (e.g. because a cpu was offlined or napi got moved to another cpu). We can't pretend the 'doubtful' entry wasn't in our list. Instead, when we don't find an entry indicate via IS_ERR that entry was removed ('did not exist' or withheld ('might-be-unconfirmed'). This most likely also fixes a xt_connlimit imbalance earlier reported by Dmitry Andrianov. Cc: Dmitry Andrianov <dmitry.andrianov@alertme.com> Reported-by: Justin Pettit <jpettit@vmware.com> Reported-by: Yi-Hung Wei <yihung.wei@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Yi-Hung Wei <yihung.wei@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> [mfo: backport: refresh context lines and use older symbol/file names: - nf_conncount.c -> xt_connlimit.c. - nf_conncount_rb -> xt_connlimit_rb - nf_conncount_tuple -> xt_connlimit_conn - conncount_conn_cachep -> connlimit_conn_cachep] Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
commit b36e4523d4d56e2595e28f16f6ccf1cd6a9fc452 upstream.

Yi-Hung Wei and Justin Pettit found a race in the garbage collection scheme
used by nf_conncount.

When doing list walk, we lookup the tuple in the conntrack table.
If the lookup fails we remove this tuple from our list because
the conntrack entry is gone.

This is the common cause, but turns out its not the only one.
The list entry could have been created just before by another cpu, i.e. the
conntrack entry might not yet have been inserted into the global hash.

The avoid this, we introduce a timestamp and the owning cpu.
If the entry appears to be stale, evict only if:
 1. The current cpu is the one that added the entry, or,
 2. The timestamp is older than two jiffies

The second constraint allows GC to be taken over by other
cpu too (e.g. because a cpu was offlined or napi got moved to another
cpu).

We can't pretend the 'doubtful' entry wasn't in our list.
Instead, when we don't find an entry indicate via IS_ERR
that entry was removed ('did not exist' or withheld
('might-be-unconfirmed').

This most likely also fixes a xt_connlimit imbalance earlier reported by
Dmitry Andrianov.

Cc: Dmitry Andrianov <dmitry.andrianov@alertme.com>
Reported-by: Justin Pettit <jpettit@vmware.com>
Reported-by: Yi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Yi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

[mfo: backport: refresh context lines and use older symbol/file names:
 - nf_conncount.c -> xt_connlimit.c.
   - nf_conncount_rb -> xt_connlimit_rb
   - nf_conncount_tuple -> xt_connlimit_conn
   - conncount_conn_cachep -> connlimit_conn_cachep]
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>

Signed-off-by: Sasha Levin <sashal@kernel.org>
netfilter: nf_conncount: Fix garbage collection with zones 2019-01-09T16:14:51+00:00 Yi-Hung Wei yihung.wei@gmail.com 2019-01-02T20:42:02+00:00 525e1dffed8711973f77412729621098a95238e5 commit 21ba8847f857028dc83a0f341e16ecc616e34740 upstream. Currently, we use check_hlist() for garbage colleciton. However, we use the ‘zone’ from the counted entry to query the existence of existing entries in the hlist. This could be wrong when they are in different zones, and this patch fixes this issue. Fixes: e59ea3df3fc2 ("netfilter: xt_connlimit: honor conntrack zone if available") Signed-off-by: Yi-Hung Wei <yihung.wei@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> [mfo: backport: refresh context lines and use older symbol/file names, note hunk 5: - nf_conncount.c -> xt_connlimit.c - nf_conncount_rb -> xt_connlimit_rb - nf_conncount_tuple -> xt_connlimit_conn - hunk 5: remove check for non-NULL 'tuple', that isn't required as it's introduced by upstream commit 35d8deb80 ("netfilter: conncount: Support count only use case") which addresses nf_conncount_count() that does not exist yet -- it's introduced by upstream commit 625c556118f3 ("netfilter: connlimit: split xt_connlimit into front and backend"), a refactor change. - nft_connlimit.c -> removed, not used/doesn't exist yet.] Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
commit 21ba8847f857028dc83a0f341e16ecc616e34740 upstream.

Currently, we use check_hlist() for garbage colleciton. However, we
use the ‘zone’ from the counted entry to query the existence of
existing entries in the hlist. This could be wrong when they are in
different zones, and this patch fixes this issue.

Fixes: e59ea3df3fc2 ("netfilter: xt_connlimit: honor conntrack zone if available")
Signed-off-by: Yi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

[mfo: backport: refresh context lines and use older symbol/file names, note hunk 5:
 - nf_conncount.c -> xt_connlimit.c
   - nf_conncount_rb -> xt_connlimit_rb
   - nf_conncount_tuple -> xt_connlimit_conn
   - hunk 5: remove check for non-NULL 'tuple', that isn't required as it's introduced
     by upstream commit 35d8deb80 ("netfilter: conncount: Support count only use case")
     which addresses nf_conncount_count() that does not exist yet -- it's introduced by
     upstream commit 625c556118f3 ("netfilter: connlimit: split xt_connlimit into front
     and backend"), a refactor change.
 - nft_connlimit.c -> removed, not used/doesn't exist yet.]
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>

Signed-off-by: Sasha Levin <sashal@kernel.org>
netfilter: nf_conncount: expose connection list interface 2019-01-09T16:14:51+00:00 Pablo Neira Ayuso pablo@netfilter.org 2019-01-02T20:42:01+00:00 15ee3595d2ac6577f179dc688137d60ee92c0984 commit 5e5cbc7b23eaf13e18652c03efbad5be6995de6a upstream. This patch provides an interface to maintain the list of connections and the lookup function to obtain the number of connections in the list. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> [mfo: backport: refresh context lines and use older symbol/file names: - nf_conntrack_count.h: new file, add include guards. - nf_conncount.c -> xt_connlimit.c. - nf_conncount_rb -> xt_connlimit_rb - nf_conncount_tuple -> xt_connlimit_conn - conncount_rb_cachep -> connlimit_rb_cachep - conncount_conn_cachep -> connlimit_conn_cachep] Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
commit 5e5cbc7b23eaf13e18652c03efbad5be6995de6a upstream.

This patch provides an interface to maintain the list of connections and
the lookup function to obtain the number of connections in the list.

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

[mfo: backport: refresh context lines and use older symbol/file names:
 - nf_conntrack_count.h: new file, add include guards.
 - nf_conncount.c -> xt_connlimit.c.
   - nf_conncount_rb -> xt_connlimit_rb
   - nf_conncount_tuple -> xt_connlimit_conn
   - conncount_rb_cachep -> connlimit_rb_cachep
   - conncount_conn_cachep -> connlimit_conn_cachep]
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>

Signed-off-by: Sasha Levin <sashal@kernel.org>
netfilter: xt_connlimit: don't store address in the conn nodes 2019-01-09T16:14:50+00:00 Florian Westphal fw@strlen.de 2019-01-02T20:42:00+00:00 5e614e212a6359af78b6034ceb12c56f71d5b423 commit ce49480dba8666cba0106e8e31a942c9ce4c438a upstream. Only stored, never read. This is a leftover from commit 7d08487777c8 ("netfilter: connlimit: use rbtree for per-host conntrack obj storage"), which added the rbtree node struct that stores the address instead. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> [mfo: backport: refresh context lines and use older symbol/file names: - nf_conncount.c -> xt_connlimit.c. - nf_conncount_rb -> xt_connlimit_rb - nf_conncount_tuple -> xt_connlimit_conn - additionally, remove the add_hlist() 'addr' parameter that isn't used and removed later upstream with commit 625c556118f3 ("netfilter: connlimit: split xt_connlimit into front and backend") in the rename from 'xt_connlimit.c' to 'nf_conncount.c', a big refactor, so do it here, while still here in this related patch.] Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
commit ce49480dba8666cba0106e8e31a942c9ce4c438a upstream.

Only stored, never read.  This is a leftover from commit 7d08487777c8
("netfilter: connlimit: use rbtree for per-host conntrack obj storage"),
which added the rbtree node struct that stores the address instead.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

[mfo: backport: refresh context lines and use older symbol/file names:
 - nf_conncount.c -> xt_connlimit.c.
   - nf_conncount_rb -> xt_connlimit_rb
   - nf_conncount_tuple -> xt_connlimit_conn
  - additionally, remove the add_hlist() 'addr' parameter that isn't used and removed
    later upstream with commit 625c556118f3 ("netfilter: connlimit: split xt_connlimit
    into front and backend") in the rename from 'xt_connlimit.c' to 'nf_conncount.c',
    a big refactor, so do it here, while still here in this related patch.]
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>

Signed-off-by: Sasha Levin <sashal@kernel.org>
netfilter: ipset: Fix wraparound in hash:*net* types 2018-12-21T13:13:10+00:00 Jozsef Kadlecsik kadlec@blackhole.kfki.hu 2018-01-12T10:16:50+00:00 5515c5bd3f560e89222cce52ea2f71c71687a2e8 [ Upstream commit 0b8d9073539e217f79ec1bff65eb205ac796723d ] Fix wraparound bug which could lead to memory exhaustion when adding an x.x.x.x-255.255.255.255 range to any hash:*net* types. Fixes Netfilter's bugzilla id #1212, reported by Thomas Schwark. Fixes: 48596a8ddc46 ("netfilter: ipset: Fix adding an IPv4 range containing more than 2^31 addresses") Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 0b8d9073539e217f79ec1bff65eb205ac796723d ]

Fix wraparound bug which could lead to memory exhaustion when adding an
x.x.x.x-255.255.255.255 range to any hash:*net* types.

Fixes Netfilter's bugzilla id #1212, reported by Thomas Schwark.

Fixes: 48596a8ddc46 ("netfilter: ipset: Fix adding an IPv4 range containing more than 2^31 addresses")
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
netfilter: nf_tables: deactivate expressions in rule replecement routine 2018-12-17T08:28:52+00:00 Taehee Yoo ap420073@gmail.com 2018-11-28T02:27:28+00:00 397727e77f2f32af322f850b457c1503acdff220 [ Upstream commit ca08987885a147643817d02bf260bc4756ce8cd4 ] There is no expression deactivation call from the rule replacement path, hence, chain counter is not decremented. A few steps to reproduce the problem: %nft add table ip filter %nft add chain ip filter c1 %nft add chain ip filter c1 %nft add rule ip filter c1 jump c2 %nft replace rule ip filter c1 handle 3 accept %nft flush ruleset <jump c2> expression means immediate NFT_JUMP to chain c2. Reference count of chain c2 is increased when the rule is added. When rule is deleted or replaced, the reference counter of c2 should be decreased via nft_rule_expr_deactivate() which calls nft_immediate_deactivate(). Splat looks like: [ 214.396453] WARNING: CPU: 1 PID: 21 at net/netfilter/nf_tables_api.c:1432 nf_tables_chain_destroy.isra.38+0x2f9/0x3a0 [nf_tables] [ 214.398983] Modules linked in: nf_tables nfnetlink [ 214.398983] CPU: 1 PID: 21 Comm: kworker/1:1 Not tainted 4.20.0-rc2+ #44 [ 214.398983] Workqueue: events nf_tables_trans_destroy_work [nf_tables] [ 214.398983] RIP: 0010:nf_tables_chain_destroy.isra.38+0x2f9/0x3a0 [nf_tables] [ 214.398983] Code: 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 8e 00 00 00 48 8b 7b 58 e8 e1 2c 4e c6 48 89 df e8 d9 2c 4e c6 eb 9a <0f> 0b eb 96 0f 0b e9 7e fe ff ff e8 a7 7e 4e c6 e9 a4 fe ff ff e8 [ 214.398983] RSP: 0018:ffff8881152874e8 EFLAGS: 00010202 [ 214.398983] RAX: 0000000000000001 RBX: ffff88810ef9fc28 RCX: ffff8881152876f0 [ 214.398983] RDX: dffffc0000000000 RSI: 1ffff11022a50ede RDI: ffff88810ef9fc78 [ 214.398983] RBP: 1ffff11022a50e9d R08: 0000000080000000 R09: 0000000000000000 [ 214.398983] R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff11022a50eba [ 214.398983] R13: ffff888114446e08 R14: ffff8881152876f0 R15: ffffed1022a50ed6 [ 214.398983] FS: 0000000000000000(0000) GS:ffff888116400000(0000) knlGS:0000000000000000 [ 214.398983] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 214.398983] CR2: 00007fab9bb5f868 CR3: 000000012aa16000 CR4: 00000000001006e0 [ 214.398983] Call Trace: [ 214.398983] ? nf_tables_table_destroy.isra.37+0x100/0x100 [nf_tables] [ 214.398983] ? __kasan_slab_free+0x145/0x180 [ 214.398983] ? nf_tables_trans_destroy_work+0x439/0x830 [nf_tables] [ 214.398983] ? kfree+0xdb/0x280 [ 214.398983] nf_tables_trans_destroy_work+0x5f5/0x830 [nf_tables] [ ... ] Fixes: bb7b40aecbf7 ("netfilter: nf_tables: bogus EBUSY in chain deletions") Reported by: Christoph Anton Mitterer <calestyo@scientia.net> Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=914505 Link: https://bugzilla.kernel.org/show_bug.cgi?id=201791 Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit ca08987885a147643817d02bf260bc4756ce8cd4 ]

There is no expression deactivation call from the rule replacement path,
hence, chain counter is not decremented. A few steps to reproduce the
problem:

   %nft add table ip filter
   %nft add chain ip filter c1
   %nft add chain ip filter c1
   %nft add rule ip filter c1 jump c2
   %nft replace rule ip filter c1 handle 3 accept
   %nft flush ruleset

<jump c2> expression means immediate NFT_JUMP to chain c2.
Reference count of chain c2 is increased when the rule is added.

When rule is deleted or replaced, the reference counter of c2 should be
decreased via nft_rule_expr_deactivate() which calls
nft_immediate_deactivate().

Splat looks like:
[  214.396453] WARNING: CPU: 1 PID: 21 at net/netfilter/nf_tables_api.c:1432 nf_tables_chain_destroy.isra.38+0x2f9/0x3a0 [nf_tables]
[  214.398983] Modules linked in: nf_tables nfnetlink
[  214.398983] CPU: 1 PID: 21 Comm: kworker/1:1 Not tainted 4.20.0-rc2+ #44
[  214.398983] Workqueue: events nf_tables_trans_destroy_work [nf_tables]
[  214.398983] RIP: 0010:nf_tables_chain_destroy.isra.38+0x2f9/0x3a0 [nf_tables]
[  214.398983] Code: 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 8e 00 00 00 48 8b 7b 58 e8 e1 2c 4e c6 48 89 df e8 d9 2c 4e c6 eb 9a <0f> 0b eb 96 0f 0b e9 7e fe ff ff e8 a7 7e 4e c6 e9 a4 fe ff ff e8
[  214.398983] RSP: 0018:ffff8881152874e8 EFLAGS: 00010202
[  214.398983] RAX: 0000000000000001 RBX: ffff88810ef9fc28 RCX: ffff8881152876f0
[  214.398983] RDX: dffffc0000000000 RSI: 1ffff11022a50ede RDI: ffff88810ef9fc78
[  214.398983] RBP: 1ffff11022a50e9d R08: 0000000080000000 R09: 0000000000000000
[  214.398983] R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff11022a50eba
[  214.398983] R13: ffff888114446e08 R14: ffff8881152876f0 R15: ffffed1022a50ed6
[  214.398983] FS:  0000000000000000(0000) GS:ffff888116400000(0000) knlGS:0000000000000000
[  214.398983] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  214.398983] CR2: 00007fab9bb5f868 CR3: 000000012aa16000 CR4: 00000000001006e0
[  214.398983] Call Trace:
[  214.398983]  ? nf_tables_table_destroy.isra.37+0x100/0x100 [nf_tables]
[  214.398983]  ? __kasan_slab_free+0x145/0x180
[  214.398983]  ? nf_tables_trans_destroy_work+0x439/0x830 [nf_tables]
[  214.398983]  ? kfree+0xdb/0x280
[  214.398983]  nf_tables_trans_destroy_work+0x5f5/0x830 [nf_tables]
[ ... ]

Fixes: bb7b40aecbf7 ("netfilter: nf_tables: bogus EBUSY in chain deletions")
Reported by: Christoph Anton Mitterer <calestyo@scientia.net>
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=914505
Link: https://bugzilla.kernel.org/show_bug.cgi?id=201791
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>