<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/netfilter, branch v6.7.8</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>netfilter: nf_tables: use kzalloc for hook allocation</title>
<updated>2024-03-01T12:41:58+00:00</updated>
<author>
<name>Florian Westphal</name>
<email>fw@strlen.de</email>
</author>
<published>2024-02-21T17:38:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=06e841cc2db607879ec530cd01bb7ca8813341c3'/>
<id>06e841cc2db607879ec530cd01bb7ca8813341c3</id>
<content type='text'>
[ Upstream commit 195e5f88c2e48330ba5483e0bad2de3b3fad484f ]

KMSAN reports unitialized variable when registering the hook,
   reg-&gt;hook_ops_type == NF_HOOK_OP_BPF)
        ~~~~~~~~~~~ undefined

This is a small structure, just use kzalloc to make sure this
won't happen again when new fields get added to nf_hook_ops.

Fixes: 7b4b2fa37587 ("netfilter: annotate nf_tables base hook ops")
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 195e5f88c2e48330ba5483e0bad2de3b3fad484f ]

KMSAN reports unitialized variable when registering the hook,
   reg-&gt;hook_ops_type == NF_HOOK_OP_BPF)
        ~~~~~~~~~~~ undefined

This is a small structure, just use kzalloc to make sure this
won't happen again when new fields get added to nf_hook_ops.

Fixes: 7b4b2fa37587 ("netfilter: annotate nf_tables base hook ops")
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: nf_tables: register hooks last when adding new chain/flowtable</title>
<updated>2024-03-01T12:41:58+00:00</updated>
<author>
<name>Pablo Neira Ayuso</name>
<email>pablo@netfilter.org</email>
</author>
<published>2024-02-19T18:43:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4d74eaaee8201e7635d38333a5e466e7484991d3'/>
<id>4d74eaaee8201e7635d38333a5e466e7484991d3</id>
<content type='text'>
[ Upstream commit d472e9853d7b46a6b094224d131d09ccd3a03daf ]

Register hooks last when adding chain/flowtable to ensure that packets do
not walk over datastructure that is being released in the error path
without waiting for the rcu grace period.

Fixes: 91c7b38dc9f0 ("netfilter: nf_tables: use new transaction infrastructure to handle chain")
Fixes: 3b49e2e94e6e ("netfilter: nf_tables: add flow table netlink frontend")
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit d472e9853d7b46a6b094224d131d09ccd3a03daf ]

Register hooks last when adding chain/flowtable to ensure that packets do
not walk over datastructure that is being released in the error path
without waiting for the rcu grace period.

Fixes: 91c7b38dc9f0 ("netfilter: nf_tables: use new transaction infrastructure to handle chain")
Fixes: 3b49e2e94e6e ("netfilter: nf_tables: add flow table netlink frontend")
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: nft_flow_offload: release dst in case direct xmit path is used</title>
<updated>2024-03-01T12:41:58+00:00</updated>
<author>
<name>Pablo Neira Ayuso</name>
<email>pablo@netfilter.org</email>
</author>
<published>2024-02-20T20:36:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2d17cf10179a7de6d8f0128168b84ad0b4a1863f'/>
<id>2d17cf10179a7de6d8f0128168b84ad0b4a1863f</id>
<content type='text'>
[ Upstream commit 8762785f459be1cfe6fcf7285c123aad6a3703f0 ]

Direct xmit does not use it since it calls dev_queue_xmit() to send
packets, hence it calls dst_release().

kmemleak reports:

unreferenced object 0xffff88814f440900 (size 184):
  comm "softirq", pid 0, jiffies 4294951896
  hex dump (first 32 bytes):
    00 60 5b 04 81 88 ff ff 00 e6 e8 82 ff ff ff ff  .`[.............
    21 0b 50 82 ff ff ff ff 00 00 00 00 00 00 00 00  !.P.............
  backtrace (crc cb2bf5d6):
    [&lt;000000003ee17107&gt;] kmem_cache_alloc+0x286/0x340
    [&lt;0000000021a5de2c&gt;] dst_alloc+0x43/0xb0
    [&lt;00000000f0671159&gt;] rt_dst_alloc+0x2e/0x190
    [&lt;00000000fe5092c9&gt;] __mkroute_output+0x244/0x980
    [&lt;000000005fb96fb0&gt;] ip_route_output_flow+0xc0/0x160
    [&lt;0000000045367433&gt;] nf_ip_route+0xf/0x30
    [&lt;0000000085da1d8e&gt;] nf_route+0x2d/0x60
    [&lt;00000000d1ecd1cb&gt;] nft_flow_route+0x171/0x6a0 [nft_flow_offload]
    [&lt;00000000d9b2fb60&gt;] nft_flow_offload_eval+0x4e8/0x700 [nft_flow_offload]
    [&lt;000000009f447dbb&gt;] expr_call_ops_eval+0x53/0x330 [nf_tables]
    [&lt;00000000072e1be6&gt;] nft_do_chain+0x17c/0x840 [nf_tables]
    [&lt;00000000d0551029&gt;] nft_do_chain_inet+0xa1/0x210 [nf_tables]
    [&lt;0000000097c9d5c6&gt;] nf_hook_slow+0x5b/0x160
    [&lt;0000000005eccab1&gt;] ip_forward+0x8b6/0x9b0
    [&lt;00000000553a269b&gt;] ip_rcv+0x221/0x230
    [&lt;00000000412872e5&gt;] __netif_receive_skb_one_core+0xfe/0x110

Fixes: fa502c865666 ("netfilter: flowtable: simplify route logic")
Reported-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 8762785f459be1cfe6fcf7285c123aad6a3703f0 ]

Direct xmit does not use it since it calls dev_queue_xmit() to send
packets, hence it calls dst_release().

kmemleak reports:

unreferenced object 0xffff88814f440900 (size 184):
  comm "softirq", pid 0, jiffies 4294951896
  hex dump (first 32 bytes):
    00 60 5b 04 81 88 ff ff 00 e6 e8 82 ff ff ff ff  .`[.............
    21 0b 50 82 ff ff ff ff 00 00 00 00 00 00 00 00  !.P.............
  backtrace (crc cb2bf5d6):
    [&lt;000000003ee17107&gt;] kmem_cache_alloc+0x286/0x340
    [&lt;0000000021a5de2c&gt;] dst_alloc+0x43/0xb0
    [&lt;00000000f0671159&gt;] rt_dst_alloc+0x2e/0x190
    [&lt;00000000fe5092c9&gt;] __mkroute_output+0x244/0x980
    [&lt;000000005fb96fb0&gt;] ip_route_output_flow+0xc0/0x160
    [&lt;0000000045367433&gt;] nf_ip_route+0xf/0x30
    [&lt;0000000085da1d8e&gt;] nf_route+0x2d/0x60
    [&lt;00000000d1ecd1cb&gt;] nft_flow_route+0x171/0x6a0 [nft_flow_offload]
    [&lt;00000000d9b2fb60&gt;] nft_flow_offload_eval+0x4e8/0x700 [nft_flow_offload]
    [&lt;000000009f447dbb&gt;] expr_call_ops_eval+0x53/0x330 [nf_tables]
    [&lt;00000000072e1be6&gt;] nft_do_chain+0x17c/0x840 [nf_tables]
    [&lt;00000000d0551029&gt;] nft_do_chain_inet+0xa1/0x210 [nf_tables]
    [&lt;0000000097c9d5c6&gt;] nf_hook_slow+0x5b/0x160
    [&lt;0000000005eccab1&gt;] ip_forward+0x8b6/0x9b0
    [&lt;00000000553a269b&gt;] ip_rcv+0x221/0x230
    [&lt;00000000412872e5&gt;] __netif_receive_skb_one_core+0xfe/0x110

Fixes: fa502c865666 ("netfilter: flowtable: simplify route logic")
Reported-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: nft_flow_offload: reset dst in route object after setting up flow</title>
<updated>2024-03-01T12:41:58+00:00</updated>
<author>
<name>Pablo Neira Ayuso</name>
<email>pablo@netfilter.org</email>
</author>
<published>2024-02-21T11:32:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=670548c8db44d76e40e1dfc06812bca36a61e9ae'/>
<id>670548c8db44d76e40e1dfc06812bca36a61e9ae</id>
<content type='text'>
[ Upstream commit 9e0f0430389be7696396c62f037be4bf72cf93e3 ]

dst is transferred to the flow object, route object does not own it
anymore.  Reset dst in route object, otherwise if flow_offload_add()
fails, error path releases dst twice, leading to a refcount underflow.

Fixes: a3c90f7a2323 ("netfilter: nf_tables: flow offload expression")
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 9e0f0430389be7696396c62f037be4bf72cf93e3 ]

dst is transferred to the flow object, route object does not own it
anymore.  Reset dst in route object, otherwise if flow_offload_add()
fails, error path releases dst twice, leading to a refcount underflow.

Fixes: a3c90f7a2323 ("netfilter: nf_tables: flow offload expression")
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: nf_tables: set dormant flag on hook register failure</title>
<updated>2024-03-01T12:41:57+00:00</updated>
<author>
<name>Florian Westphal</name>
<email>fw@strlen.de</email>
</author>
<published>2024-02-19T15:58:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6f2496366426cec18ba53f1c7f6c3ac307ca6a95'/>
<id>6f2496366426cec18ba53f1c7f6c3ac307ca6a95</id>
<content type='text'>
[ Upstream commit bccebf64701735533c8db37773eeacc6566cc8ec ]

We need to set the dormant flag again if we fail to register
the hooks.

During memory pressure hook registration can fail and we end up
with a table marked as active but no registered hooks.

On table/base chain deletion, nf_tables will attempt to unregister
the hook again which yields a warn splat from the nftables core.

Reported-and-tested-by: syzbot+de4025c006ec68ac56fc@syzkaller.appspotmail.com
Fixes: 179d9ba5559a ("netfilter: nf_tables: fix table flag updates")
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit bccebf64701735533c8db37773eeacc6566cc8ec ]

We need to set the dormant flag again if we fail to register
the hooks.

During memory pressure hook registration can fail and we end up
with a table marked as active but no registered hooks.

On table/base chain deletion, nf_tables will attempt to unregister
the hook again which yields a warn splat from the nftables core.

Reported-and-tested-by: syzbot+de4025c006ec68ac56fc@syzkaller.appspotmail.com
Fixes: 179d9ba5559a ("netfilter: nf_tables: fix table flag updates")
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: conntrack: check SCTP_CID_SHUTDOWN_ACK for vtag setting in sctp_new</title>
<updated>2024-03-01T12:41:37+00:00</updated>
<author>
<name>Xin Long</name>
<email>lucien.xin@gmail.com</email>
</author>
<published>2024-01-25T22:29:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=435e999e41fd0abdc1ab49c4d028047c11e47562'/>
<id>435e999e41fd0abdc1ab49c4d028047c11e47562</id>
<content type='text'>
[ Upstream commit 6e348067ee4bc5905e35faa3a8fafa91c9124bc7 ]

The annotation says in sctp_new(): "If it is a shutdown ack OOTB packet, we
expect a return shutdown complete, otherwise an ABORT Sec 8.4 (5) and (8)".
However, it does not check SCTP_CID_SHUTDOWN_ACK before setting vtag[REPLY]
in the conntrack entry(ct).

Because of that, if the ct in Router disappears for some reason in [1]
with the packet sequence like below:

   Client &gt; Server: sctp (1) [INIT] [init tag: 3201533963]
   Server &gt; Client: sctp (1) [INIT ACK] [init tag: 972498433]
   Client &gt; Server: sctp (1) [COOKIE ECHO]
   Server &gt; Client: sctp (1) [COOKIE ACK]
   Client &gt; Server: sctp (1) [DATA] (B)(E) [TSN: 3075057809]
   Server &gt; Client: sctp (1) [SACK] [cum ack 3075057809]
   Server &gt; Client: sctp (1) [HB REQ]
   (the ct in Router disappears somehow)  &lt;-------- [1]
   Client &gt; Server: sctp (1) [HB ACK]
   Client &gt; Server: sctp (1) [DATA] (B)(E) [TSN: 3075057810]
   Client &gt; Server: sctp (1) [DATA] (B)(E) [TSN: 3075057810]
   Client &gt; Server: sctp (1) [HB REQ]
   Client &gt; Server: sctp (1) [DATA] (B)(E) [TSN: 3075057810]
   Client &gt; Server: sctp (1) [HB REQ]
   Client &gt; Server: sctp (1) [ABORT]

when processing HB ACK packet in Router it calls sctp_new() to initialize
the new ct with vtag[REPLY] set to HB_ACK packet's vtag.

Later when sending DATA from Client, all the SACKs from Server will get
dropped in Router, as the SACK packet's vtag does not match vtag[REPLY]
in the ct. The worst thing is the vtag in this ct will never get fixed
by the upcoming packets from Server.

This patch fixes it by checking SCTP_CID_SHUTDOWN_ACK before setting
vtag[REPLY] in the ct in sctp_new() as the annotation says. With this
fix, it will leave vtag[REPLY] in ct to 0 in the case above, and the
next HB REQ/ACK from Server is able to fix the vtag as its value is 0
in nf_conntrack_sctp_packet().

Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 6e348067ee4bc5905e35faa3a8fafa91c9124bc7 ]

The annotation says in sctp_new(): "If it is a shutdown ack OOTB packet, we
expect a return shutdown complete, otherwise an ABORT Sec 8.4 (5) and (8)".
However, it does not check SCTP_CID_SHUTDOWN_ACK before setting vtag[REPLY]
in the conntrack entry(ct).

Because of that, if the ct in Router disappears for some reason in [1]
with the packet sequence like below:

   Client &gt; Server: sctp (1) [INIT] [init tag: 3201533963]
   Server &gt; Client: sctp (1) [INIT ACK] [init tag: 972498433]
   Client &gt; Server: sctp (1) [COOKIE ECHO]
   Server &gt; Client: sctp (1) [COOKIE ACK]
   Client &gt; Server: sctp (1) [DATA] (B)(E) [TSN: 3075057809]
   Server &gt; Client: sctp (1) [SACK] [cum ack 3075057809]
   Server &gt; Client: sctp (1) [HB REQ]
   (the ct in Router disappears somehow)  &lt;-------- [1]
   Client &gt; Server: sctp (1) [HB ACK]
   Client &gt; Server: sctp (1) [DATA] (B)(E) [TSN: 3075057810]
   Client &gt; Server: sctp (1) [DATA] (B)(E) [TSN: 3075057810]
   Client &gt; Server: sctp (1) [HB REQ]
   Client &gt; Server: sctp (1) [DATA] (B)(E) [TSN: 3075057810]
   Client &gt; Server: sctp (1) [HB REQ]
   Client &gt; Server: sctp (1) [ABORT]

when processing HB ACK packet in Router it calls sctp_new() to initialize
the new ct with vtag[REPLY] set to HB_ACK packet's vtag.

Later when sending DATA from Client, all the SACKs from Server will get
dropped in Router, as the SACK packet's vtag does not match vtag[REPLY]
in the ct. The worst thing is the vtag in this ct will never get fixed
by the upcoming packets from Server.

This patch fixes it by checking SCTP_CID_SHUTDOWN_ACK before setting
vtag[REPLY] in the ct in sctp_new() as the annotation says. With this
fix, it will leave vtag[REPLY] in ct to 0 in the case above, and the
next HB REQ/ACK from Server is able to fix the vtag as its value is 0
in nf_conntrack_sctp_packet().

Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: ipset: Missing gc cancellations fixed</title>
<updated>2024-02-23T08:51:58+00:00</updated>
<author>
<name>Jozsef Kadlecsik</name>
<email>kadlec@netfilter.org</email>
</author>
<published>2024-02-04T15:26:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=46fe5e8bba98f696252dd39a596acdf10039fab2'/>
<id>46fe5e8bba98f696252dd39a596acdf10039fab2</id>
<content type='text'>
commit 27c5a095e2518975e20a10102908ae8231699879 upstream.

The patch fdb8e12cc2cc ("netfilter: ipset: fix performance regression
in swap operation") missed to add the calls to gc cancellations
at the error path of create operations and at module unload. Also,
because the half of the destroy operations now executed by a
function registered by call_rcu(), neither NFNL_SUBSYS_IPSET mutex
or rcu read lock is held and therefore the checking of them results
false warnings.

Fixes: 97f7cf1cd80e ("netfilter: ipset: fix performance regression in swap operation")
Reported-by: syzbot+52bbc0ad036f6f0d4a25@syzkaller.appspotmail.com
Reported-by: Brad Spengler &lt;spender@grsecurity.net&gt;
Reported-by: Стас Ничипорович &lt;stasn77@gmail.com&gt;
Tested-by: Brad Spengler &lt;spender@grsecurity.net&gt;
Tested-by: Стас Ничипорович &lt;stasn77@gmail.com&gt;
Signed-off-by: Jozsef Kadlecsik &lt;kadlec@netfilter.org&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 27c5a095e2518975e20a10102908ae8231699879 upstream.

The patch fdb8e12cc2cc ("netfilter: ipset: fix performance regression
in swap operation") missed to add the calls to gc cancellations
at the error path of create operations and at module unload. Also,
because the half of the destroy operations now executed by a
function registered by call_rcu(), neither NFNL_SUBSYS_IPSET mutex
or rcu read lock is held and therefore the checking of them results
false warnings.

Fixes: 97f7cf1cd80e ("netfilter: ipset: fix performance regression in swap operation")
Reported-by: syzbot+52bbc0ad036f6f0d4a25@syzkaller.appspotmail.com
Reported-by: Brad Spengler &lt;spender@grsecurity.net&gt;
Reported-by: Стас Ничипорович &lt;stasn77@gmail.com&gt;
Tested-by: Brad Spengler &lt;spender@grsecurity.net&gt;
Tested-by: Стас Ничипорович &lt;stasn77@gmail.com&gt;
Signed-off-by: Jozsef Kadlecsik &lt;kadlec@netfilter.org&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: ipset: fix performance regression in swap operation</title>
<updated>2024-02-23T08:51:58+00:00</updated>
<author>
<name>Jozsef Kadlecsik</name>
<email>kadlec@netfilter.org</email>
</author>
<published>2024-01-29T09:57:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=970709a67696b100a57b33af1a3d75fc34b747eb'/>
<id>970709a67696b100a57b33af1a3d75fc34b747eb</id>
<content type='text'>
commit 97f7cf1cd80eeed3b7c808b7c12463295c751001 upstream.

The patch "netfilter: ipset: fix race condition between swap/destroy
and kernel side add/del/test", commit 28628fa9 fixes a race condition.
But the synchronize_rcu() added to the swap function unnecessarily slows
it down: it can safely be moved to destroy and use call_rcu() instead.

Eric Dumazet pointed out that simply calling the destroy functions as
rcu callback does not work: sets with timeout use garbage collectors
which need cancelling at destroy which can wait. Therefore the destroy
functions are split into two: cancelling garbage collectors safely at
executing the command received by netlink and moving the remaining
part only into the rcu callback.

Link: https://lore.kernel.org/lkml/C0829B10-EAA6-4809-874E-E1E9C05A8D84@automattic.com/
Fixes: 28628fa952fe ("netfilter: ipset: fix race condition between swap/destroy and kernel side add/del/test")
Reported-by: Ale Crismani &lt;ale.crismani@automattic.com&gt;
Reported-by: David Wang &lt;00107082@163.com&gt;
Tested-by: David Wang &lt;00107082@163.com&gt;
Signed-off-by: Jozsef Kadlecsik &lt;kadlec@netfilter.org&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 97f7cf1cd80eeed3b7c808b7c12463295c751001 upstream.

The patch "netfilter: ipset: fix race condition between swap/destroy
and kernel side add/del/test", commit 28628fa9 fixes a race condition.
But the synchronize_rcu() added to the swap function unnecessarily slows
it down: it can safely be moved to destroy and use call_rcu() instead.

Eric Dumazet pointed out that simply calling the destroy functions as
rcu callback does not work: sets with timeout use garbage collectors
which need cancelling at destroy which can wait. Therefore the destroy
functions are split into two: cancelling garbage collectors safely at
executing the command received by netlink and moving the remaining
part only into the rcu callback.

Link: https://lore.kernel.org/lkml/C0829B10-EAA6-4809-874E-E1E9C05A8D84@automattic.com/
Fixes: 28628fa952fe ("netfilter: ipset: fix race condition between swap/destroy and kernel side add/del/test")
Reported-by: Ale Crismani &lt;ale.crismani@automattic.com&gt;
Reported-by: David Wang &lt;00107082@163.com&gt;
Tested-by: David Wang &lt;00107082@163.com&gt;
Signed-off-by: Jozsef Kadlecsik &lt;kadlec@netfilter.org&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>work around gcc bugs with 'asm goto' with outputs</title>
<updated>2024-02-23T08:51:20+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-02-09T20:39:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1bfa8bc86cc788c9c30430f52011c06f11abccd0'/>
<id>1bfa8bc86cc788c9c30430f52011c06f11abccd0</id>
<content type='text'>
commit 4356e9f841f7fbb945521cef3577ba394c65f3fc upstream.

We've had issues with gcc and 'asm goto' before, and we created a
'asm_volatile_goto()' macro for that in the past: see commits
3f0116c3238a ("compiler/gcc4: Add quirk for 'asm goto' miscompilation
bug") and a9f180345f53 ("compiler/gcc4: Make quirk for
asm_volatile_goto() unconditional").

Then, much later, we ended up removing the workaround in commit
43c249ea0b1e ("compiler-gcc.h: remove ancient workaround for gcc PR
58670") because we no longer supported building the kernel with the
affected gcc versions, but we left the macro uses around.

Now, Sean Christopherson reports a new version of a very similar
problem, which is fixed by re-applying that ancient workaround.  But the
problem in question is limited to only the 'asm goto with outputs'
cases, so instead of re-introducing the old workaround as-is, let's
rename and limit the workaround to just that much less common case.

It looks like there are at least two separate issues that all hit in
this area:

 (a) some versions of gcc don't mark the asm goto as 'volatile' when it
     has outputs:

        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98619
        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110420

     which is easy to work around by just adding the 'volatile' by hand.

 (b) Internal compiler errors:

        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110422

     which are worked around by adding the extra empty 'asm' as a
     barrier, as in the original workaround.

but the problem Sean sees may be a third thing since it involves bad
code generation (not an ICE) even with the manually added 'volatile'.

but the same old workaround works for this case, even if this feels a
bit like voodoo programming and may only be hiding the issue.

Reported-and-tested-by: Sean Christopherson &lt;seanjc@google.com&gt;
Link: https://lore.kernel.org/all/20240208220604.140859-1-seanjc@google.com/
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Uros Bizjak &lt;ubizjak@gmail.com&gt;
Cc: Jakub Jelinek &lt;jakub@redhat.com&gt;
Cc: Andrew Pinski &lt;quic_apinski@quicinc.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 4356e9f841f7fbb945521cef3577ba394c65f3fc upstream.

We've had issues with gcc and 'asm goto' before, and we created a
'asm_volatile_goto()' macro for that in the past: see commits
3f0116c3238a ("compiler/gcc4: Add quirk for 'asm goto' miscompilation
bug") and a9f180345f53 ("compiler/gcc4: Make quirk for
asm_volatile_goto() unconditional").

Then, much later, we ended up removing the workaround in commit
43c249ea0b1e ("compiler-gcc.h: remove ancient workaround for gcc PR
58670") because we no longer supported building the kernel with the
affected gcc versions, but we left the macro uses around.

Now, Sean Christopherson reports a new version of a very similar
problem, which is fixed by re-applying that ancient workaround.  But the
problem in question is limited to only the 'asm goto with outputs'
cases, so instead of re-introducing the old workaround as-is, let's
rename and limit the workaround to just that much less common case.

It looks like there are at least two separate issues that all hit in
this area:

 (a) some versions of gcc don't mark the asm goto as 'volatile' when it
     has outputs:

        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98619
        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110420

     which is easy to work around by just adding the 'volatile' by hand.

 (b) Internal compiler errors:

        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110422

     which are worked around by adding the extra empty 'asm' as a
     barrier, as in the original workaround.

but the problem Sean sees may be a third thing since it involves bad
code generation (not an ICE) even with the manually added 'volatile'.

but the same old workaround works for this case, even if this feels a
bit like voodoo programming and may only be hiding the issue.

Reported-and-tested-by: Sean Christopherson &lt;seanjc@google.com&gt;
Link: https://lore.kernel.org/all/20240208220604.140859-1-seanjc@google.com/
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Uros Bizjak &lt;ubizjak@gmail.com&gt;
Cc: Jakub Jelinek &lt;jakub@redhat.com&gt;
Cc: Andrew Pinski &lt;quic_apinski@quicinc.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: nft_set_rbtree: skip end interval element from gc</title>
<updated>2024-02-16T18:14:32+00:00</updated>
<author>
<name>Pablo Neira Ayuso</name>
<email>pablo@netfilter.org</email>
</author>
<published>2024-02-07T17:49:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6eb14441f10602fa1cf691da9d685718b68b78a9'/>
<id>6eb14441f10602fa1cf691da9d685718b68b78a9</id>
<content type='text'>
commit 60c0c230c6f046da536d3df8b39a20b9a9fd6af0 upstream.

rbtree lazy gc on insert might collect an end interval element that has
been just added in this transactions, skip end interval elements that
are not yet active.

Fixes: f718863aca46 ("netfilter: nft_set_rbtree: fix overlap expiration walk")
Cc: stable@vger.kernel.org
Reported-by: lonial con &lt;kongln9170@gmail.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 60c0c230c6f046da536d3df8b39a20b9a9fd6af0 upstream.

rbtree lazy gc on insert might collect an end interval element that has
been just added in this transactions, skip end interval elements that
are not yet active.

Fixes: f718863aca46 ("netfilter: nft_set_rbtree: fix overlap expiration walk")
Cc: stable@vger.kernel.org
Reported-by: lonial con &lt;kongln9170@gmail.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
