16265 Commits

Author SHA1 Message Date
John Fastabend
a5c3f2b4ce bpf: syzkaller found null ptr deref in unix_bpf proto add
commit 8d6650646ce49e9a5b8c5c23eb94f74b1749f70f upstream.

I added logic to track the sock pair for stream_unix sockets so that we
ensure lifetime of the sock matches the time a sockmap could reference
the sock (see fixes tag). I forgot though that we allow af_unix unconnected
sockets into a sock{map|hash} map.

This is problematic because previous fixed expected sk_pair() to exist
and did not NULL check it. Because unconnected sockets have a NULL
sk_pair this resulted in the NULL ptr dereference found by syzkaller.

BUG: KASAN: null-ptr-deref in unix_stream_bpf_update_proto+0x72/0x430 net/unix/unix_bpf.c:171
Write of size 4 at addr 0000000000000080 by task syz-executor360/5073
Call Trace:
 <TASK>
 ...
 sock_hold include/net/sock.h:777 [inline]
 unix_stream_bpf_update_proto+0x72/0x430 net/unix/unix_bpf.c:171
 sock_map_init_proto net/core/sock_map.c:190 [inline]
 sock_map_link+0xb87/0x1100 net/core/sock_map.c:294
 sock_map_update_common+0xf6/0x870 net/core/sock_map.c:483
 sock_map_update_elem_sys+0x5b6/0x640 net/core/sock_map.c:577
 bpf_map_update_value+0x3af/0x820 kernel/bpf/syscall.c:167

We considered just checking for the null ptr and skipping taking a ref
on the NULL peer sock. But, if the socket is then connected() after
being added to the sockmap we can cause the original issue again. So
instead this patch blocks adding af_unix sockets that are not in the
ESTABLISHED state.

Reported-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot+e8030702aefd3444fb9e@syzkaller.appspotmail.com
Fixes: 8866730aed51 ("bpf, sockmap: af_unix stream sockets need to hold ref for pair sock")
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20231201180139.328529-2-john.fastabend@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-10 17:10:36 +01:00
Vlad Buslov
7cbdf36eab net/sched: act_ct: Always fill offloading tuple iifidx
commit 9bc64bd0cd765f696fcd40fc98909b1f7c73b2ba upstream.

Referenced commit doesn't always set iifidx when offloading the flow to
hardware. Fix the following cases:

- nf_conn_act_ct_ext_fill() is called before extension is created with
nf_conn_act_ct_ext_add() in tcf_ct_act(). This can cause rule offload with
unspecified iifidx when connection is offloaded after only single
original-direction packet has been processed by tc data path. Always fill
the new nf_conn_act_ct_ext instance after creating it in
nf_conn_act_ct_ext_add().

- Offloading of unidirectional UDP NEW connections is now supported, but ct
flow iifidx field is not updated when connection is promoted to
bidirectional which can result reply-direction iifidx to be zero when
refreshing the connection. Fill in the extension and update flow iifidx
before calling flow_offload_refresh().

Fixes: 9795ded7f924 ("net/sched: act_ct: Fill offloading tuple iifidx")
Reviewed-by: Paul Blakey <paulb@nvidia.com>
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Fixes: 6a9bad0069cf ("net/sched: act_ct: offload UDP NEW connections")
Link: https://lore.kernel.org/r/20231103151410.764271-1-vladbu@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-10 17:10:36 +01:00
Vlad Buslov
a29b15cc68 net/sched: act_ct: Take per-cb reference to tcf_ct_flow_table
[ Upstream commit 125f1c7f26ffcdbf96177abe75b70c1a6ceb17bc ]

The referenced change added custom cleanup code to act_ct to delete any
callbacks registered on the parent block when deleting the
tcf_ct_flow_table instance. However, the underlying issue is that the
drivers don't obtain the reference to the tcf_ct_flow_table instance when
registering callbacks which means that not only driver callbacks may still
be on the table when deleting it but also that the driver can still have
pointers to its internal nf_flowtable and can use it concurrently which
results either warning in netfilter[0] or use-after-free.

Fix the issue by taking a reference to the underlying struct
tcf_ct_flow_table instance when registering the callback and release the
reference when unregistering. Expose new API required for such reference
counting by adding two new callbacks to nf_flowtable_type and implementing
them for act_ct flowtable_ct type. This fixes the issue by extending the
lifetime of nf_flowtable until all users have unregistered.

[0]:
[106170.938634] ------------[ cut here ]------------
[106170.939111] WARNING: CPU: 21 PID: 3688 at include/net/netfilter/nf_flow_table.h:262 mlx5_tc_ct_del_ft_cb+0x267/0x2b0 [mlx5_core]
[106170.940108] Modules linked in: act_ct nf_flow_table act_mirred act_skbedit act_tunnel_key vxlan cls_matchall nfnetlink_cttimeout act_gact cls_flower sch_ingress mlx5_vdpa vringh vhost_iotlb vdpa bonding openvswitch nsh rpcrdma rdma_ucm
ib_iser libiscsi scsi_transport_iscsi ib_umad rdma_cm ib_ipoib iw_cm ib_cm mlx5_ib ib_uverbs ib_core xt_MASQUERADE nf_conntrack_netlink nfnetlink iptable_nat xt_addrtype xt_conntrack nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcgss oid_regis
try overlay mlx5_core
[106170.943496] CPU: 21 PID: 3688 Comm: kworker/u48:0 Not tainted 6.6.0-rc7_for_upstream_min_debug_2023_11_01_13_02 #1
[106170.944361] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[106170.945292] Workqueue: mlx5e mlx5e_rep_neigh_update [mlx5_core]
[106170.945846] RIP: 0010:mlx5_tc_ct_del_ft_cb+0x267/0x2b0 [mlx5_core]
[106170.946413] Code: 89 ef 48 83 05 71 a4 14 00 01 e8 f4 06 04 e1 48 83 05 6c a4 14 00 01 48 83 c4 28 5b 5d 41 5c 41 5d c3 48 83 05 d1 8b 14 00 01 <0f> 0b 48 83 05 d7 8b 14 00 01 e9 96 fe ff ff 48 83 05 a2 90 14 00
[106170.947924] RSP: 0018:ffff88813ff0fcb8 EFLAGS: 00010202
[106170.948397] RAX: 0000000000000000 RBX: ffff88811eabac40 RCX: ffff88811eabad48
[106170.949040] RDX: ffff88811eab8000 RSI: ffffffffa02cd560 RDI: 0000000000000000
[106170.949679] RBP: ffff88811eab8000 R08: 0000000000000001 R09: ffffffffa0229700
[106170.950317] R10: ffff888103538fc0 R11: 0000000000000001 R12: ffff88811eabad58
[106170.950969] R13: ffff888110c01c00 R14: ffff888106b40000 R15: 0000000000000000
[106170.951616] FS:  0000000000000000(0000) GS:ffff88885fd40000(0000) knlGS:0000000000000000
[106170.952329] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[106170.952834] CR2: 00007f1cefd28cb0 CR3: 000000012181b006 CR4: 0000000000370ea0
[106170.953482] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[106170.954121] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[106170.954766] Call Trace:
[106170.955057]  <TASK>
[106170.955315]  ? __warn+0x79/0x120
[106170.955648]  ? mlx5_tc_ct_del_ft_cb+0x267/0x2b0 [mlx5_core]
[106170.956172]  ? report_bug+0x17c/0x190
[106170.956537]  ? handle_bug+0x3c/0x60
[106170.956891]  ? exc_invalid_op+0x14/0x70
[106170.957264]  ? asm_exc_invalid_op+0x16/0x20
[106170.957666]  ? mlx5_del_flow_rules+0x10/0x310 [mlx5_core]
[106170.958172]  ? mlx5_tc_ct_block_flow_offload_add+0x1240/0x1240 [mlx5_core]
[106170.958788]  ? mlx5_tc_ct_del_ft_cb+0x267/0x2b0 [mlx5_core]
[106170.959339]  ? mlx5_tc_ct_del_ft_cb+0xc6/0x2b0 [mlx5_core]
[106170.959854]  ? mapping_remove+0x154/0x1d0 [mlx5_core]
[106170.960342]  ? mlx5e_tc_action_miss_mapping_put+0x4f/0x80 [mlx5_core]
[106170.960927]  mlx5_tc_ct_delete_flow+0x76/0xc0 [mlx5_core]
[106170.961441]  mlx5_free_flow_attr_actions+0x13b/0x220 [mlx5_core]
[106170.962001]  mlx5e_tc_del_fdb_flow+0x22c/0x3b0 [mlx5_core]
[106170.962524]  mlx5e_tc_del_flow+0x95/0x3c0 [mlx5_core]
[106170.963034]  mlx5e_flow_put+0x73/0xe0 [mlx5_core]
[106170.963506]  mlx5e_put_flow_list+0x38/0x70 [mlx5_core]
[106170.964002]  mlx5e_rep_update_flows+0xec/0x290 [mlx5_core]
[106170.964525]  mlx5e_rep_neigh_update+0x1da/0x310 [mlx5_core]
[106170.965056]  process_one_work+0x13a/0x2c0
[106170.965443]  worker_thread+0x2e5/0x3f0
[106170.965808]  ? rescuer_thread+0x410/0x410
[106170.966192]  kthread+0xc6/0xf0
[106170.966515]  ? kthread_complete_and_exit+0x20/0x20
[106170.966970]  ret_from_fork+0x2d/0x50
[106170.967332]  ? kthread_complete_and_exit+0x20/0x20
[106170.967774]  ret_from_fork_asm+0x11/0x20
[106170.970466]  </TASK>
[106170.970726] ---[ end trace 0000000000000000 ]---

Fixes: 77ac5e40c44e ("net/sched: act_ct: remove and free nf_table callbacks")
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Reviewed-by: Paul Blakey <paulb@nvidia.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:34 +01:00
Pablo Neira Ayuso
2bb4ecb334 netfilter: flowtable: GC pushes back packets to classic path
[ Upstream commit 735795f68b37e9bb49f642407a0d49b1631ea1c7 ]

Since 41f2c7c342d3 ("net/sched: act_ct: Fix promotion of offloaded
unreplied tuple"), flowtable GC pushes back flows with IPS_SEEN_REPLY
back to classic path in every run, ie. every second. This is because of
a new check for NF_FLOW_HW_ESTABLISHED which is specific of sched/act_ct.

In Netfilter's flowtable case, NF_FLOW_HW_ESTABLISHED never gets set on
and IPS_SEEN_REPLY is unreliable since users decide when to offload the
flow before, such bit might be set on at a later stage.

Fix it by adding a custom .gc handler that sched/act_ct can use to
deal with its NF_FLOW_HW_ESTABLISHED bit.

Fixes: 41f2c7c342d3 ("net/sched: act_ct: Fix promotion of offloaded unreplied tuple")
Reported-by: Vladimir Smelhaus <vl.sm@email.cz>
Reviewed-by: Paul Blakey <paulb@nvidia.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: 125f1c7f26ff ("net/sched: act_ct: Take per-cb reference to tcf_ct_flow_table")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:34 +01:00
Paul Blakey
df01de08b4 net/sched: act_ct: Fix promotion of offloaded unreplied tuple
[ Upstream commit 41f2c7c342d3adb1c4dd5f2e3dd831adff16a669 ]

Currently UNREPLIED and UNASSURED connections are added to the nf flow
table. This causes the following connection packets to be processed
by the flow table which then skips conntrack_in(), and thus such the
connections will remain UNREPLIED and UNASSURED even if reply traffic
is then seen. Even still, the unoffloaded reply packets are the ones
triggering hardware update from new to established state, and if
there aren't any to triger an update and/or previous update was
missed, hardware can get out of sync with sw and still mark
packets as new.

Fix the above by:
1) Not skipping conntrack_in() for UNASSURED packets, but still
   refresh for hardware, as before the cited patch.
2) Try and force a refresh by reply-direction packets that update
   the hardware rules from new to established state.
3) Remove any bidirectional flows that didn't failed to update in
   hardware for re-insertion as bidrectional once any new packet
   arrives.

Fixes: 6a9bad0069cf ("net/sched: act_ct: offload UDP NEW connections")
Co-developed-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Paul Blakey <paulb@nvidia.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/1686313379-117663-1-git-send-email-paulb@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Stable-dep-of: 125f1c7f26ff ("net/sched: act_ct: Take per-cb reference to tcf_ct_flow_table")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:34 +01:00
Vlad Buslov
8b160f2fba netfilter: flowtable: cache info of last offload
[ Upstream commit 1a441a9b8be8849957a01413a144f84932c324cb ]

Modify flow table offload to cache the last ct info status that was passed
to the driver offload callbacks by extending enum nf_flow_flags with new
"NF_FLOW_HW_ESTABLISHED" flag. Set the flag if ctinfo was 'established'
during last act_ct meta actions fill call. This infrastructure change is
necessary to optimize promoting of UDP connections from 'new' to
'established' in following patches in this series.

Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 125f1c7f26ff ("net/sched: act_ct: Take per-cb reference to tcf_ct_flow_table")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:34 +01:00
Vlad Buslov
c29a7656f8 netfilter: flowtable: allow unidirectional rules
[ Upstream commit 8f84780b84d645d6e35467f4a6f3236b20d7f4b2 ]

Modify flow table offload to support unidirectional connections by
extending enum nf_flow_flags with new "NF_FLOW_HW_BIDIRECTIONAL" flag. Only
offload reply direction when the flag is set. This infrastructure change is
necessary to support offloading UDP NEW connections in original direction
in following patches in series.

Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 125f1c7f26ff ("net/sched: act_ct: Take per-cb reference to tcf_ct_flow_table")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:34 +01:00
John Fastabend
90d1f74c3c bpf, sockmap: af_unix stream sockets need to hold ref for pair sock
[ Upstream commit 8866730aed5100f06d3d965c22f1c61f74942541 ]

AF_UNIX stream sockets are a paired socket. So sending on one of the pairs
will lookup the paired socket as part of the send operation. It is possible
however to put just one of the pairs in a BPF map. This currently increments
the refcnt on the sock in the sockmap to ensure it is not free'd by the
stack before sockmap cleans up its state and stops any skbs being sent/recv'd
to that socket.

But we missed a case. If the peer socket is closed it will be free'd by the
stack. However, the paired socket can still be referenced from BPF sockmap
side because we hold a reference there. Then if we are sending traffic through
BPF sockmap to that socket it will try to dereference the free'd pair in its
send logic creating a use after free. And following splat:

   [59.900375] BUG: KASAN: slab-use-after-free in sk_wake_async+0x31/0x1b0
   [59.901211] Read of size 8 at addr ffff88811acbf060 by task kworker/1:2/954
   [...]
   [59.905468] Call Trace:
   [59.905787]  <TASK>
   [59.906066]  dump_stack_lvl+0x130/0x1d0
   [59.908877]  print_report+0x16f/0x740
   [59.910629]  kasan_report+0x118/0x160
   [59.912576]  sk_wake_async+0x31/0x1b0
   [59.913554]  sock_def_readable+0x156/0x2a0
   [59.914060]  unix_stream_sendmsg+0x3f9/0x12a0
   [59.916398]  sock_sendmsg+0x20e/0x250
   [59.916854]  skb_send_sock+0x236/0xac0
   [59.920527]  sk_psock_backlog+0x287/0xaa0

To fix let BPF sockmap hold a refcnt on both the socket in the sockmap and its
paired socket. It wasn't obvious how to contain the fix to bpf_unix logic. The
primarily problem with keeping this logic in bpf_unix was: In the sock close()
we could handle the deref by having a close handler. But, when we are destroying
the psock through a map delete operation we wouldn't have gotten any signal
thorugh the proto struct other than it being replaced. If we do the deref from
the proto replace its too early because we need to deref the sk_pair after the
backlog worker has been stopped.

Given all this it seems best to just cache it at the end of the psock and eat 8B
for the af_unix and vsock users. Notice dgram sockets are OK because they handle
locking already.

Fixes: 94531cfcbe79 ("af_unix: Add unix_stream_proto for sockmap")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20231129012557.95371-2-john.fastabend@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:32 +01:00
Eric Dumazet
8d929b6c11 udp: lockless UDP_ENCAP_L2TPINUDP / UDP_GRO
[ Upstream commit ac9a7f4ce5dda1472e8f44096f33066c6ec1a3b4 ]

Move udp->encap_enabled to udp->udp_flags.

Add udp_test_and_set_bit() helper to allow lockless
udp_tunnel_encap_enable() implementation.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Stable-dep-of: 70a36f571362 ("udp: annotate data-races around udp->encap_type")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:28 +01:00
David Howells
2489502fb1 ipv4, ipv6: Use splice_eof() to flush
[ Upstream commit 1d7e4538a5463faa0b0e26a7a7b6bd68c7dfdd78 ]

Allow splice to undo the effects of MSG_MORE after prematurely ending a
splice/sendfile due to getting an EOF condition (->splice_read() returned
0) after splice had called sendmsg() with MSG_MORE set when the user didn't
set MSG_MORE.

For UDP, a pending packet will not be emitted if the socket is closed
before it is flushed; with this change, it be flushed by ->splice_eof().

For TCP, it's not clear that MSG_MORE is actually effective.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/CAHk-=wh=V579PDYvkpnTobCLGczbgxpMgGmmhqiTyE34Cpi5Gg@mail.gmail.com/
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Kuniyuki Iwashima <kuniyu@amazon.com>
cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
cc: David Ahern <dsahern@kernel.org>
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: a0002127cd74 ("udp: move udp->no_check6_tx to udp->udp_flags")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:27 +01:00
David Howells
4713b7c756 splice, net: Add a splice_eof op to file-ops and socket-ops
[ Upstream commit 2bfc66850952b6921b2033b09729ec59eabbc81d ]

Add an optional method, ->splice_eof(), to allow splice to indicate the
premature termination of a splice to struct file_operations and struct
proto_ops.

This is called if sendfile() or splice() encounters all of the following
conditions inside splice_direct_to_actor():

 (1) the user did not set SPLICE_F_MORE (splice only), and

 (2) an EOF condition occurred (->splice_read() returned 0), and

 (3) we haven't read enough to fulfill the request (ie. len > 0 still), and

 (4) we have already spliced at least one byte.

A further patch will modify the behaviour of SPLICE_F_MORE to always be
passed to the actor if either the user set it or we haven't yet read
sufficient data to fulfill the request.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/CAHk-=wh=V579PDYvkpnTobCLGczbgxpMgGmmhqiTyE34Cpi5Gg@mail.gmail.com/
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
cc: Jens Axboe <axboe@kernel.dk>
cc: Christoph Hellwig <hch@lst.de>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: Matthew Wilcox <willy@infradead.org>
cc: Jan Kara <jack@suse.cz>
cc: Jeff Layton <jlayton@kernel.org>
cc: David Hildenbrand <david@redhat.com>
cc: Christian Brauner <brauner@kernel.org>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Boris Pismenny <borisp@nvidia.com>
cc: John Fastabend <john.fastabend@gmail.com>
cc: linux-mm@kvack.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: a0002127cd74 ("udp: move udp->no_check6_tx to udp->udp_flags")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:27 +01:00
Eric Dumazet
c48fcb4f49 net: annotate data-races around sk->sk_tsflags
[ Upstream commit e3390b30a5dfb112e8e802a59c0f68f947b638b2 ]

sk->sk_tsflags can be read locklessly, add corresponding annotations.

Fixes: b9f40e21ef42 ("net-timestamp: move timestamp flags out of sk_flags")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 7f6ca95d16b9 ("net: Implement missing getsockopt(SO_TIMESTAMPING_NEW)")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:23 +01:00
Pablo Neira Ayuso
282e3fb612 netfilter: nf_tables: set transport offset from mac header for netdev/egress
[ Upstream commit 0ae8e4cca78781401b17721bfb72718fdf7b4912 ]

Before this patch, transport offset (pkt->thoff) provides an offset
relative to the network header. This is fine for the inet families
because skb->data points to the network header in such case. However,
from netdev/egress, skb->data points to the mac header (if available),
thus, pkt->thoff is missing the mac header length.

Add skb_network_offset() to the transport offset (pkt->thoff) for
netdev, so transport header mangling works as expected. Adjust payload
fast eval function to use skb->data now that pkt->thoff provides an
absolute offset. This explains why users report that matching on
egress/netdev works but payload mangling does not.

This patch implicitly fixes payload mangling for IPv4 packets in
netdev/egress given skb_store_bits() requires an offset from skb->data
to reach the transport header.

I suspect that nft_exthdr and the trace infra were also broken from
netdev/egress because they also take skb->data as start, and pkt->thoff
was not correct.

Note that IPv6 is fine because ipv6_find_hdr() already provides a
transport offset starting from skb->data, which includes
skb_network_offset().

The bridge family also uses nft_set_pktinfo_ipv4_validate(), but there
skb_network_offset() is zero, so the update in this patch does not alter
the existing behaviour.

Fixes: 42df6e1d221d ("netfilter: Introduce egress hook")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:21 +01:00
Xin Long
9487cc4c90 netfilter: use skb_ip_totlen and iph_totlen
[ Upstream commit a13fbf5ed5b4fc9095f12e955ca3a59b5507ff01 ]

There are also quite some places in netfilter that may process IPv4 TCP
GSO packets, we need to replace them too.

In length_mt(), we have to use u_int32_t/int to accept skb_ip_totlen()
return value, otherwise it may overflow and mismatch. This change will
also help us add selftest for IPv4 BIG TCP in the following patch.

Note that we don't need to replace the one in tcpmss_tg4(), as it will
return if there is data after tcphdr in tcpmss_mangle_packet(). The
same in mangle_contents() in nf_nat_helper.c, it returns false when
skb->len + extra > 65535 in enlarge_skb().

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 0ae8e4cca787 ("netfilter: nf_tables: set transport offset from mac header for netdev/egress")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:21 +01:00
Xiao Yao
39347d6450 Bluetooth: MGMT/SMP: Fix address type when using SMP over BREDR/LE
commit 59b047bc98084f8af2c41483e4d68a5adf2fa7f7 upstream.

If two Bluetooth devices both support BR/EDR and BLE, and also
support Secure Connections, then they only need to pair once.
The LTK generated during the LE pairing process may be converted
into a BR/EDR link key for BR/EDR transport, and conversely, a
link key generated during the BR/EDR SSP pairing process can be
converted into an LTK for LE transport. Hence, the link type of
the link key and LTK is not fixed, they can be either an LE LINK
or an ACL LINK.

Currently, in the mgmt_new_irk/ltk/crsk/link_key functions, the
link type is fixed, which could lead to incorrect address types
being reported to the application layer. Therefore, it is necessary
to add link_type/addr_type to the smp_irk/ltk/crsk and link_key,
to ensure the generation of the correct address type.

SMP over BREDR:
Before Fix:
> ACL Data RX: Handle 11 flags 0x02 dlen 12
        BR/EDR SMP: Identity Address Information (0x09) len 7
        Address: F8:7D:76:F2:12:F3 (OUI F8-7D-76)
@ MGMT Event: New Identity Resolving Key (0x0018) plen 30
        Random address: 00:00:00:00:00:00 (Non-Resolvable)
        LE Address: F8:7D:76:F2:12:F3 (OUI F8-7D-76)
@ MGMT Event: New Long Term Key (0x000a) plen 37
        LE Address: F8:7D:76:F2:12:F3 (OUI F8-7D-76)
        Key type: Authenticated key from P-256 (0x03)

After Fix:
> ACL Data RX: Handle 11 flags 0x02 dlen 12
      BR/EDR SMP: Identity Address Information (0x09) len 7
        Address: F8:7D:76:F2:12:F3 (OUI F8-7D-76)
@ MGMT Event: New Identity Resolving Key (0x0018) plen 30
        Random address: 00:00:00:00:00:00 (Non-Resolvable)
        BR/EDR Address: F8:7D:76:F2:12:F3 (OUI F8-7D-76)
@ MGMT Event: New Long Term Key (0x000a) plen 37
        BR/EDR Address: F8:7D:76:F2:12:F3 (OUI F8-7D-76)
        Key type: Authenticated key from P-256 (0x03)

SMP over LE:
Before Fix:
@ MGMT Event: New Identity Resolving Key (0x0018) plen 30
        Random address: 5F:5C:07:37:47:D5 (Resolvable)
        LE Address: F8:7D:76:F2:12:F3 (OUI F8-7D-76)
@ MGMT Event: New Long Term Key (0x000a) plen 37
        LE Address: F8:7D:76:F2:12:F3 (OUI F8-7D-76)
        Key type: Authenticated key from P-256 (0x03)
@ MGMT Event: New Link Key (0x0009) plen 26
        BR/EDR Address: F8:7D:76:F2:12:F3 (OUI F8-7D-76)
        Key type: Authenticated Combination key from P-256 (0x08)

After Fix:
@ MGMT Event: New Identity Resolving Key (0x0018) plen 30
        Random address: 5E:03:1C:00:38:21 (Resolvable)
        LE Address: F8:7D:76:F2:12:F3 (OUI F8-7D-76)
@ MGMT Event: New Long Term Key (0x000a) plen 37
        LE Address: F8:7D:76:F2:12:F3 (OUI F8-7D-76)
        Key type: Authenticated key from P-256 (0x03)
@ MGMT Event: New Link Key (0x0009) plen 26
        Store hint: Yes (0x01)
        LE Address: F8:7D:76:F2:12:F3 (OUI F8-7D-76)
        Key type: Authenticated Combination key from P-256 (0x08)

Cc: stable@vger.kernel.org
Signed-off-by: Xiao Yao <xiaoyao@rock-chips.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-01 12:39:03 +00:00
Maciej Żenczykowski
0da41ddfb2 net: ipv6: support reporting otherwise unknown prefix flags in RTM_NEWPREFIX
[ Upstream commit bd4a816752bab609dd6d65ae021387beb9e2ddbd ]

Lorenzo points out that we effectively clear all unknown
flags from PIO when copying them to userspace in the netlink
RTM_NEWPREFIX notification.

We could fix this one at a time as new flags are defined,
or in one fell swoop - I choose the latter.

We could either define 6 new reserved flags (reserved1..6) and handle
them individually (and rename them as new flags are defined), or we
could simply copy the entire unmodified byte over - I choose the latter.

This unfortunately requires some anonymous union/struct magic,
so we add a static assert on the struct size for a little extra safety.

Cc: David Ahern <dsahern@kernel.org>
Cc: Lorenzo Colitti <lorenzo@google.com>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-20 17:00:15 +01:00
Ido Schimmel
b5ca945612 drop_monitor: Require 'CAP_SYS_ADMIN' when joining "events" group
[ Upstream commit e03781879a0d524ce3126678d50a80484a513c4b ]

The "NET_DM" generic netlink family notifies drop locations over the
"events" multicast group. This is problematic since by default generic
netlink allows non-root users to listen to these notifications.

Fix by adding a new field to the generic netlink multicast group
structure that when set prevents non-root users or root without the
'CAP_SYS_ADMIN' capability (in the user namespace owning the network
namespace) from joining the group. Set this field for the "events"
group. Use 'CAP_SYS_ADMIN' rather than 'CAP_NET_ADMIN' because of the
nature of the information that is shared over this group.

Note that the capability check in this case will always be performed
against the initial user namespace since the family is not netns aware
and only operates in the initial network namespace.

A new field is added to the structure rather than using the "flags"
field because the existing field uses uAPI flags and it is inappropriate
to add a new uAPI flag for an internal kernel check. In net-next we can
rework the "flags" field to use internal flags and fold the new field
into it. But for now, in order to reduce the amount of changes, add a
new field.

Since the information can only be consumed by root, mark the control
plane operations that start and stop the tracing as root-only using the
'GENL_ADMIN_PERM' flag.

Tested using [1].

Before:

 # capsh -- -c ./dm_repo
 # capsh --drop=cap_sys_admin -- -c ./dm_repo

After:

 # capsh -- -c ./dm_repo
 # capsh --drop=cap_sys_admin -- -c ./dm_repo
 Failed to join "events" multicast group

[1]
 $ cat dm.c
 #include <stdio.h>
 #include <netlink/genl/ctrl.h>
 #include <netlink/genl/genl.h>
 #include <netlink/socket.h>

 int main(int argc, char **argv)
 {
 	struct nl_sock *sk;
 	int grp, err;

 	sk = nl_socket_alloc();
 	if (!sk) {
 		fprintf(stderr, "Failed to allocate socket\n");
 		return -1;
 	}

 	err = genl_connect(sk);
 	if (err) {
 		fprintf(stderr, "Failed to connect socket\n");
 		return err;
 	}

 	grp = genl_ctrl_resolve_grp(sk, "NET_DM", "events");
 	if (grp < 0) {
 		fprintf(stderr,
 			"Failed to resolve \"events\" multicast group\n");
 		return grp;
 	}

 	err = nl_socket_add_memberships(sk, grp, NFNLGRP_NONE);
 	if (err) {
 		fprintf(stderr, "Failed to join \"events\" multicast group\n");
 		return err;
 	}

 	return 0;
 }
 $ gcc -I/usr/include/libnl3 -lnl-3 -lnl-genl-3 -o dm_repo dm.c

Fixes: 9a8afc8d3962 ("Network Drop Monitor: Adding drop monitor implementation & Netlink protocol")
Reported-by: "The UK's National Cyber Security Centre (NCSC)" <security@ncsc.gov.uk>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20231206213102.1824398-3-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13 18:39:12 +01:00
Paolo Abeni
c91685ac1b tcp: fix mid stream window clamp.
[ Upstream commit 58d3aade20cdddbac6c9707ac0f3f5f8c1278b74 ]

After the blamed commit below, if the user-space application performs
window clamping when tp->rcv_wnd is 0, the TCP socket will never be
able to announce a non 0 receive window, even after completely emptying
the receive buffer and re-setting the window clamp to higher values.

Refactor tcp_set_window_clamp() to address the issue: when the user
decreases the current clamp value, set rcv_ssthresh according to the
same logic used at buffer initialization, but ensuring reserved mem
provisioning.

To avoid code duplication factor-out the relevant bits from
tcp_adjust_rcv_ssthresh() in a new helper and reuse it in the above
scenario.

When increasing the clamp value, give the rcv_ssthresh a chance to grow
according to previously implemented heuristic.

Fixes: 3aa7857fe1d7 ("tcp: enable mid stream window clamp")
Reported-by: David Gibson <david@gibson.dropbear.id.au>
Reported-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/705dad54e6e6e9a010e571bf58e0b35a8ae70503.1701706073.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13 18:39:09 +01:00
Dan Carpenter
18a169810c netfilter: nf_tables: fix pointer math issue in nft_byteorder_eval()
[ Upstream commit c301f0981fdd3fd1ffac6836b423c4d7a8e0eb63 ]

The problem is in nft_byteorder_eval() where we are iterating through a
loop and writing to dst[0], dst[1], dst[2] and so on...  On each
iteration we are writing 8 bytes.  But dst[] is an array of u32 so each
element only has space for 4 bytes.  That means that every iteration
overwrites part of the previous element.

I spotted this bug while reviewing commit caf3ef7468f7 ("netfilter:
nf_tables: prevent OOB access in nft_byteorder_eval") which is a related
issue.  I think that the reason we have not detected this bug in testing
is that most of time we only write one element.

Fixes: ce1e7989d989 ("netfilter: nft_byteorder: provide 64bit le/be conversion")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 17:07:05 +00:00
Eric Dumazet
1c6a6c926a net: annotate data-races around sk->sk_dst_pending_confirm
[ Upstream commit eb44ad4e635132754bfbcb18103f1dcb7058aedd ]

This field can be read or written without socket lock being held.

Add annotations to avoid load-store tearing.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 17:06:56 +00:00
Eric Dumazet
e7960d2a09 net: annotate data-races around sk->sk_tx_queue_mapping
[ Upstream commit 0bb4d124d34044179b42a769a0c76f389ae973b6 ]

This field can be read or written without socket lock being held.

Add annotations to avoid load-store tearing.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 17:06:56 +00:00
Johannes Berg
25bc87768c wifi: cfg80211: fix kernel-doc for wiphy_delayed_work_flush()
commit 8c73d5248dcf112611654bcd32352dc330b02397 upstream.

Clearly, there's no space in the function name, not sure how
that could've happened. Put the underscore that it should be.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 56cfb8ce1f7f ("wifi: cfg80211: add flush functions for wiphy work")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-20 11:52:18 +01:00
Jeremy Sowden
8fa280d1a9 netfilter: nft_redir: use struct nf_nat_range2 throughout and deduplicate eval call-backs
[ Upstream commit 6f56ad1b92328997e1b1792047099df6f8d7acb5 ]

`nf_nat_redirect_ipv4` takes a `struct nf_nat_ipv4_multi_range_compat`,
but converts it internally to a `struct nf_nat_range2`.  Change the
function to take the latter, factor out the code now shared with
`nf_nat_redirect_ipv6`, move the conversion to the xt_REDIRECT module,
and update the ipv4 range initialization in the nft_redir module.

Replace a bare hex constant for 127.0.0.1 with a macro.

Remove `WARN_ON`.  `nf_nat_setup_info` calls `nf_ct_is_confirmed`:

	/* Can't setup nat info for confirmed ct. */
	if (nf_ct_is_confirmed(ct))
		return NF_ACCEPT;

This means that `ct` cannot be null or the kernel will crash, and
implies that `ctinfo` is `IP_CT_NEW` or `IP_CT_RELATED`.

nft_redir has separate ipv4 and ipv6 call-backs which share much of
their code, and an inet one switch containing a switch that calls one of
the others based on the family of the packet.  Merge the ipv4 and ipv6
ones into the inet one in order to get rid of the duplicate code.

Const-qualify the `priv` pointer since we don't need to write through
it.

Assign `priv->flags` to the range instead of OR-ing it in.

Set the `NF_NAT_RANGE_PROTO_SPECIFIED` flag once during init, rather
than on every eval.

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Stable-dep-of: 80abbe8a8263 ("netfilter: nat: fix ipv6 nat redirect with mapped and scoped addresses")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 11:52:17 +01:00
Eric Dumazet
612c22e928 inet: shrink struct flowi_common
[ Upstream commit 1726483b79a72e0150734d5367e4a0238bf8fcff ]

I am looking at syzbot reports triggering kernel stack overflows
involving a cascade of ipvlan devices.

We can save 8 bytes in struct flowi_common.

This patch alone will not fix the issue, but is a start.

Fixes: 24ba14406c5c ("route: Add multipath_hash in flowi_common to make user-define hash")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: wenxu <wenxu@ucloud.cn>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20231025141037.3448203-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 11:52:15 +01:00
Eric Dumazet
6d88d4b1bb tcp: fix cookie_init_timestamp() overflows
[ Upstream commit 73ed8e03388d16c12fc577e5c700b58a29045a15 ]

cookie_init_timestamp() is supposed to return a 64bit timestamp
suitable for both TSval determination and setting of skb->tstamp.

Unfortunately it uses 32bit fields and overflows after
2^32 * 10^6 nsec (~49 days) of uptime.

Generated TSval are still correct, but skb->tstamp might be set
far away in the past, potentially confusing other layers.

tcp_ns_to_ts() is changed to return a full 64bit value,
ts and ts_now variables are changed to u64 type,
and TSMASK is removed in favor of shifts operations.

While we are at it, change this sequence:
		ts >>= TSBITS;
		ts--;
		ts <<= TSBITS;
		ts |= options;
to:
		ts -= (1UL << TSBITS);

Fixes: 9a568de4818d ("tcp: switch TCP TS option (RFC 7323) to 1ms clock")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 11:51:54 +01:00
Johannes Berg
697fb94e3e wifi: cfg80211: add flush functions for wiphy work
[ Upstream commit 56cfb8ce1f7f6c4e5ca571a2ec0880e131cd0311 ]

There may be sometimes reasons to actually run the work
if it's pending, add flush functions for both regular and
delayed wiphy work that will do this.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Stable-dep-of: eadfb54756ae ("wifi: mac80211: move sched-scan stop work to wiphy work")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 11:51:51 +01:00
Kees Cook
c04f416730 Bluetooth: hci_sock: Correctly bounds check and pad HCI_MON_NEW_INDEX name
commit cb3871b1cd135a6662b732fbc6b3db4afcdb4a64 upstream.

The code pattern of memcpy(dst, src, strlen(src)) is almost always
wrong. In this case it is wrong because it leaves memory uninitialized
if it is less than sizeof(ni->name), and overflows ni->name when longer.

Normally strtomem_pad() could be used here, but since ni->name is a
trailing array in struct hci_mon_new_index, compilers that don't support
-fstrict-flex-arrays=3 can't tell how large this array is via
__builtin_object_size(). Instead, open-code the helper and use sizeof()
since it will work correctly.

Additionally mark ni->name as __nonstring since it appears to not be a
%NUL terminated C string.

Cc: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Cc: Edward AD <twuufnxlz@gmail.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: linux-bluetooth@vger.kernel.org
Cc: netdev@vger.kernel.org
Fixes: 18f547f3fc07 ("Bluetooth: hci_sock: fix slab oob read in create_monitor_event")
Link: https://lore.kernel.org/lkml/202310110908.F2639D3276@keescook/
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25 12:03:16 +02:00
Paolo Abeni
ec9bc89a01 tcp: allow again tcp_disconnect() when threads are waiting
[ Upstream commit 419ce133ab928ab5efd7b50b2ef36ddfd4eadbd2 ]

As reported by Tom, .NET and applications build on top of it rely
on connect(AF_UNSPEC) to async cancel pending I/O operations on TCP
socket.

The blamed commit below caused a regression, as such cancellation
can now fail.

As suggested by Eric, this change addresses the problem explicitly
causing blocking I/O operation to terminate immediately (with an error)
when a concurrent disconnect() is executed.

Instead of tracking the number of threads blocked on a given socket,
track the number of disconnect() issued on such socket. If such counter
changes after a blocking operation releasing and re-acquiring the socket
lock, error out the current operation.

Fixes: 4faeee0cf8a5 ("tcp: deny tcp_disconnect() when threads are waiting")
Reported-by: Tom Deseyn <tdeseyn@redhat.com>
Closes: https://bugzilla.redhat.com/show_bug.cgi?id=1886305
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/f3b95e47e3dbed840960548aebaa8d954372db41.1697008693.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-25 12:03:12 +02:00
Hangbin Liu
ffbb01fe9a ipv4/fib: send notify when delete source address routes
[ Upstream commit 4b2b606075e50cdae62ab2356b0a1e206947c354 ]

After deleting an interface address in fib_del_ifaddr(), the function
scans the fib_info list for stray entries and calls fib_flush() and
fib_table_flush(). Then the stray entries will be deleted silently and no
RTM_DELROUTE notification will be sent.

This lack of notification can make routing daemons, or monitor like
`ip monitor route` miss the routing changes. e.g.

+ ip link add dummy1 type dummy
+ ip link add dummy2 type dummy
+ ip link set dummy1 up
+ ip link set dummy2 up
+ ip addr add 192.168.5.5/24 dev dummy1
+ ip route add 7.7.7.0/24 dev dummy2 src 192.168.5.5
+ ip -4 route
7.7.7.0/24 dev dummy2 scope link src 192.168.5.5
192.168.5.0/24 dev dummy1 proto kernel scope link src 192.168.5.5
+ ip monitor route
+ ip addr del 192.168.5.5/24 dev dummy1
Deleted 192.168.5.0/24 dev dummy1 proto kernel scope link src 192.168.5.5
Deleted broadcast 192.168.5.255 dev dummy1 table local proto kernel scope link src 192.168.5.5
Deleted local 192.168.5.5 dev dummy1 table local proto kernel scope host src 192.168.5.5

As Ido reminded, fib_table_flush() isn't only called when an address is
deleted, but also when an interface is deleted or put down. The lack of
notification in these cases is deliberate. And commit 7c6bb7d2faaf
("net/ipv6: Add knob to skip DELROUTE message on device down") introduced
a sysctl to make IPv6 behave like IPv4 in this regard. So we can't send
the route delete notify blindly in fib_table_flush().

To fix this issue, let's add a new flag in "struct fib_info" to track the
deleted prefer source address routes, and only send notify for them.

After update:
+ ip monitor route
+ ip addr del 192.168.5.5/24 dev dummy1
Deleted 192.168.5.0/24 dev dummy1 proto kernel scope link src 192.168.5.5
Deleted broadcast 192.168.5.255 dev dummy1 table local proto kernel scope link src 192.168.5.5
Deleted local 192.168.5.5 dev dummy1 table local proto kernel scope host src 192.168.5.5
Deleted 7.7.7.0/24 dev dummy2 scope link src 192.168.5.5

Suggested-by: Thomas Haller <thaller@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230922075508.848925-1-liuhangbin@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-25 12:03:11 +02:00
Luiz Augusto von Dentz
a55d53ad5c Bluetooth: hci_core: Fix build warnings
[ Upstream commit dcda165706b9fbfd685898d46a6749d7d397e0c0 ]

This fixes the following warnings:

net/bluetooth/hci_core.c: In function ‘hci_register_dev’:
net/bluetooth/hci_core.c:2620:54: warning: ‘%d’ directive output may
be truncated writing between 1 and 10 bytes into a region of size 5
[-Wformat-truncation=]
 2620 |         snprintf(hdev->name, sizeof(hdev->name), "hci%d", id);
      |                                                      ^~
net/bluetooth/hci_core.c:2620:50: note: directive argument in the range
[0, 2147483647]
 2620 |         snprintf(hdev->name, sizeof(hdev->name), "hci%d", id);
      |                                                  ^~~~~~~
net/bluetooth/hci_core.c:2620:9: note: ‘snprintf’ output between 5 and
14 bytes into a destination of size 8
 2620 |         snprintf(hdev->name, sizeof(hdev->name), "hci%d", id);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-25 12:03:10 +02:00
Neal Cardwell
4e1f3457e9 tcp: fix excessive TLP and RACK timeouts from HZ rounding
commit 1c2709cfff1dedbb9591e989e2f001484208d914 upstream.

We discovered from packet traces of slow loss recovery on kernels with
the default HZ=250 setting (and min_rtt < 1ms) that after reordering,
when receiving a SACKed sequence range, the RACK reordering timer was
firing after about 16ms rather than the desired value of roughly
min_rtt/4 + 2ms. The problem is largely due to the RACK reorder timer
calculation adding in TCP_TIMEOUT_MIN, which is 2 jiffies. On kernels
with HZ=250, this is 2*4ms = 8ms. The TLP timer calculation has the
exact same issue.

This commit fixes the TLP transmit timer and RACK reordering timer
floor calculation to more closely match the intended 2ms floor even on
kernels with HZ=250. It does this by adding in a new
TCP_TIMEOUT_MIN_US floor of 2000 us and then converting to jiffies,
instead of the current approach of converting to jiffies and then
adding th TCP_TIMEOUT_MIN value of 2 jiffies.

Our testing has verified that on kernels with HZ=1000, as expected,
this does not produce significant changes in behavior, but on kernels
with the default HZ=250 the latency improvement can be large. For
example, our tests show that for HZ=250 kernels at low RTTs this fix
roughly halves the latency for the RACK reorder timer: instead of
mostly firing at 16ms it mostly fires at 8ms.

Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Fixes: bb4d991a28cc ("tcp: adjust tail loss probe timeout")
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20231015174700.2206872-1-ncardwell.sw@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25 12:03:06 +02:00
Eric Dumazet
b372db2b8d xfrm: fix a data-race in xfrm_gen_index()
commit 3e4bc23926b83c3c67e5f61ae8571602754131a6 upstream.

xfrm_gen_index() mutual exclusion uses net->xfrm.xfrm_policy_lock.

This means we must use a per-netns idx_generator variable,
instead of a static one.
Alternative would be to use an atomic variable.

syzbot reported:

BUG: KCSAN: data-race in xfrm_sk_policy_insert / xfrm_sk_policy_insert

write to 0xffffffff87005938 of 4 bytes by task 29466 on cpu 0:
xfrm_gen_index net/xfrm/xfrm_policy.c:1385 [inline]
xfrm_sk_policy_insert+0x262/0x640 net/xfrm/xfrm_policy.c:2347
xfrm_user_policy+0x413/0x540 net/xfrm/xfrm_state.c:2639
do_ipv6_setsockopt+0x1317/0x2ce0 net/ipv6/ipv6_sockglue.c:943
ipv6_setsockopt+0x57/0x130 net/ipv6/ipv6_sockglue.c:1012
rawv6_setsockopt+0x21e/0x410 net/ipv6/raw.c:1054
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3697
__sys_setsockopt+0x1c9/0x230 net/socket.c:2263
__do_sys_setsockopt net/socket.c:2274 [inline]
__se_sys_setsockopt net/socket.c:2271 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2271
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffffffff87005938 of 4 bytes by task 29460 on cpu 1:
xfrm_sk_policy_insert+0x13e/0x640
xfrm_user_policy+0x413/0x540 net/xfrm/xfrm_state.c:2639
do_ipv6_setsockopt+0x1317/0x2ce0 net/ipv6/ipv6_sockglue.c:943
ipv6_setsockopt+0x57/0x130 net/ipv6/ipv6_sockglue.c:1012
rawv6_setsockopt+0x21e/0x410 net/ipv6/raw.c:1054
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3697
__sys_setsockopt+0x1c9/0x230 net/socket.c:2263
__do_sys_setsockopt net/socket.c:2274 [inline]
__se_sys_setsockopt net/socket.c:2271 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2271
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00006ad8 -> 0x00006b18

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 29460 Comm: syz-executor.1 Not tainted 6.5.0-rc5-syzkaller-00243-g9106536c1aa3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023

Fixes: 1121994c803f ("netns xfrm: policy insertion in netns")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25 12:03:06 +02:00
mfreemon@cloudflare.com
0796c53424 tcp: enforce receive buffer memory limits by allowing the tcp window to shrink
[ Upstream commit b650d953cd391595e536153ce30b4aab385643ac ]

Under certain circumstances, the tcp receive buffer memory limit
set by autotuning (sk_rcvbuf) is increased due to incoming data
packets as a result of the window not closing when it should be.
This can result in the receive buffer growing all the way up to
tcp_rmem[2], even for tcp sessions with a low BDP.

To reproduce:  Connect a TCP session with the receiver doing
nothing and the sender sending small packets (an infinite loop
of socket send() with 4 bytes of payload with a sleep of 1 ms
in between each send()).  This will cause the tcp receive buffer
to grow all the way up to tcp_rmem[2].

As a result, a host can have individual tcp sessions with receive
buffers of size tcp_rmem[2], and the host itself can reach tcp_mem
limits, causing the host to go into tcp memory pressure mode.

The fundamental issue is the relationship between the granularity
of the window scaling factor and the number of byte ACKed back
to the sender.  This problem has previously been identified in
RFC 7323, appendix F [1].

The Linux kernel currently adheres to never shrinking the window.

In addition to the overallocation of memory mentioned above, the
current behavior is functionally incorrect, because once tcp_rmem[2]
is reached when no remediations remain (i.e. tcp collapse fails to
free up any more memory and there are no packets to prune from the
out-of-order queue), the receiver will drop in-window packets
resulting in retransmissions and an eventual timeout of the tcp
session.  A receive buffer full condition should instead result
in a zero window and an indefinite wait.

In practice, this problem is largely hidden for most flows.  It
is not applicable to mice flows.  Elephant flows can send data
fast enough to "overrun" the sk_rcvbuf limit (in a single ACK),
triggering a zero window.

But this problem does show up for other types of flows.  Examples
are websockets and other type of flows that send small amounts of
data spaced apart slightly in time.  In these cases, we directly
encounter the problem described in [1].

RFC 7323, section 2.4 [2], says there are instances when a retracted
window can be offered, and that TCP implementations MUST ensure
that they handle a shrinking window, as specified in RFC 1122,
section 4.2.2.16 [3].  All prior RFCs on the topic of tcp window
management have made clear that sender must accept a shrunk window
from the receiver, including RFC 793 [4] and RFC 1323 [5].

This patch implements the functionality to shrink the tcp window
when necessary to keep the right edge within the memory limit by
autotuning (sk_rcvbuf).  This new functionality is enabled with
the new sysctl: net.ipv4.tcp_shrink_window

Additional information can be found at:
https://blog.cloudflare.com/unbounded-memory-usage-by-tcp-for-receive-buffers-and-how-we-fixed-it/

[1] https://www.rfc-editor.org/rfc/rfc7323#appendix-F
[2] https://www.rfc-editor.org/rfc/rfc7323#section-2.4
[3] https://www.rfc-editor.org/rfc/rfc1122#page-91
[4] https://www.rfc-editor.org/rfc/rfc793
[5] https://www.rfc-editor.org/rfc/rfc1323

Signed-off-by: Mike Freemon <mfreemon@cloudflare.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-19 23:08:54 +02:00
Radu Pirea (NXP OSS)
0d86ad068c net: macsec: indicate next pn update when offloading
[ Upstream commit 0412cc846a1ef38697c3f321f9b174da91ecd3b5 ]

Indicate next PN update using update_pn flag in macsec_context.
Offloaded MACsec implementations does not know whether or not the
MACSEC_SA_ATTR_PN attribute was passed for an SA update and assume
that next PN should always updated, but this is not always true.

The PN can be reset to its initial value using the following command:
$ ip macsec set macsec0 tx sa 0 off #octeontx2-pf case

Or, the update PN command will succeed even if the driver does not support
PN updates.
$ ip macsec set macsec0 tx sa 0 pn 1 on #mscc phy driver case

Comparing the initial PN with the new PN value is not a solution. When
the user updates the PN using its initial value the command will
succeed, even if the driver does not support it. Like this:
$ ip macsec add macsec0 tx sa 0 pn 1 on key 00 \
ead3664f508eb06c40ac7104cdae4ce5
$ ip macsec set macsec0 tx sa 0 pn 1 on #mlx5 case

Signed-off-by: Radu Pirea (NXP OSS) <radu-nicolae.pirea@oss.nxp.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Stable-dep-of: e0a8c918daa5 ("net: phy: mscc: macsec: reject PN update requests")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-19 23:08:53 +02:00
Eric Dumazet
fd32f1eee6 ipv6: remove nexthop_fib6_nh_bh()
commit ef1148d4487438a3408d6face2a8360d91b4af70 upstream.

After blamed commit, nexthop_fib6_nh_bh() and nexthop_fib6_nh()
are the same.

Delete nexthop_fib6_nh_bh(), and convert /proc/net/ipv6_route
to standard rcu to avoid this splat:

[ 5723.180080] WARNING: suspicious RCU usage
[ 5723.180083] -----------------------------
[ 5723.180084] include/net/nexthop.h:516 suspicious rcu_dereference_check() usage!
[ 5723.180086]
other info that might help us debug this:

[ 5723.180087]
rcu_scheduler_active = 2, debug_locks = 1
[ 5723.180089] 2 locks held by cat/55856:
[ 5723.180091] #0: ffff9440a582afa8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter (fs/seq_file.c:188)
[ 5723.180100] #1: ffffffffaac07040 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire (include/linux/rcupdate.h:326)
[ 5723.180109]
stack backtrace:
[ 5723.180111] CPU: 14 PID: 55856 Comm: cat Tainted: G S        I        6.3.0-dbx-DEV #528
[ 5723.180115] Call Trace:
[ 5723.180117]  <TASK>
[ 5723.180119] dump_stack_lvl (lib/dump_stack.c:107)
[ 5723.180124] dump_stack (lib/dump_stack.c:114)
[ 5723.180126] lockdep_rcu_suspicious (include/linux/context_tracking.h:122)
[ 5723.180132] ipv6_route_seq_show (include/net/nexthop.h:?)
[ 5723.180135] ? ipv6_route_seq_next (net/ipv6/ip6_fib.c:2605)
[ 5723.180140] seq_read_iter (fs/seq_file.c:272)
[ 5723.180145] seq_read (fs/seq_file.c:163)
[ 5723.180151] proc_reg_read (fs/proc/inode.c:316 fs/proc/inode.c:328)
[ 5723.180155] vfs_read (fs/read_write.c:468)
[ 5723.180160] ? up_read (kernel/locking/rwsem.c:1617)
[ 5723.180164] ksys_read (fs/read_write.c:613)
[ 5723.180168] __x64_sys_read (fs/read_write.c:621)
[ 5723.180170] do_syscall_64 (arch/x86/entry/common.c:?)
[ 5723.180174] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
[ 5723.180177] RIP: 0033:0x7fa455677d2a

Fixes: 09eed1192cec ("neighbour: switch to standard rcu, instead of rcu_bh")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230510154646.370659-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-10 22:00:46 +02:00
Jakub Kicinski
1a6e2da05f netlink: split up copies in the ack construction
[ Upstream commit 738136a0e3757a8534df3ad97d6ff6d7f429f6c1 ]

Clean up the use of unsafe_memcpy() by adding a flexible array
at the end of netlink message header and splitting up the header
and data copies.

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: d0f95894fda7 ("netlink: annotate data-races around sk->sk_err")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10 22:00:44 +02:00
Neal Cardwell
4acf07bafb tcp: fix quick-ack counting to count actual ACKs of new data
[ Upstream commit 059217c18be6757b95bfd77ba53fb50b48b8a816 ]

This commit fixes quick-ack counting so that it only considers that a
quick-ack has been provided if we are sending an ACK that newly
acknowledges data.

The code was erroneously using the number of data segments in outgoing
skbs when deciding how many quick-ack credits to remove. This logic
does not make sense, and could cause poor performance in
request-response workloads, like RPC traffic, where requests or
responses can be multi-segment skbs.

When a TCP connection decides to send N quick-acks, that is to
accelerate the cwnd growth of the congestion control module
controlling the remote endpoint of the TCP connection. That quick-ack
decision is purely about the incoming data and outgoing ACKs. It has
nothing to do with the outgoing data or the size of outgoing data.

And in particular, an ACK only serves the intended purpose of allowing
the remote congestion control to grow the congestion window quickly if
the ACK is ACKing or SACKing new data.

The fix is simple: only count packets as serving the goal of the
quickack mechanism if they are ACKing/SACKing new data. We can tell
whether this is the case by checking inet_csk_ack_scheduled(), since
we schedule an ACK exactly when we are ACKing/SACKing new data.

Fixes: fc6415bcb0f5 ("[TCP]: Fix quick-ack decrementing with TSO.")
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Yuchung Cheng <ycheng@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20231001151239.1866845-1-ncardwell.sw@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10 22:00:43 +02:00
Eric Dumazet
a8ed1b2e16 neighbour: fix data-races around n->output
[ Upstream commit 5baa0433a15eadd729625004c37463acb982eca7 ]

n->output field can be read locklessly, while a writer
might change the pointer concurrently.

Add missing annotations to prevent load-store tearing.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10 22:00:42 +02:00
Eric Dumazet
2b76aad68b neighbour: switch to standard rcu, instead of rcu_bh
[ Upstream commit 09eed1192cec1755967f2af8394207acdde579a1 ]

rcu_bh is no longer a win, especially for objects freed
with standard call_rcu().

Switch neighbour code to no longer disable BH when not necessary.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 5baa0433a15e ("neighbour: fix data-races around n->output")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10 22:00:42 +02:00
Eric Dumazet
0526933c10 neighbour: annotate lockless accesses to n->nud_state
[ Upstream commit b071af523579df7341cabf0f16fc661125e9a13f ]

We have many lockless accesses to n->nud_state.

Before adding another one in the following patch,
add annotations to readers and writers.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 5baa0433a15e ("neighbour: fix data-races around n->output")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10 22:00:42 +02:00
Johannes Berg
42970d32fe wifi: cfg80211: add missing kernel-doc for cqm_rssi_work
[ Upstream commit d1383077c225ceb87ac7a3b56b2c505193f77ed7 ]

As reported by Stephen, I neglected to add the kernel-doc
for the new struct member. Fix that.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 37c20b2effe9 ("wifi: cfg80211: fix cqm_config access race")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10 22:00:40 +02:00
Johannes Berg
c797498e86 wifi: cfg80211: fix cqm_config access race
[ Upstream commit 37c20b2effe987b806c8de6d12978e4ffeff026f ]

Max Schulze reports crashes with brcmfmac. The reason seems
to be a race between userspace removing the CQM config and
the driver calling cfg80211_cqm_rssi_notify(), where if the
data is freed while cfg80211_cqm_rssi_notify() runs it will
crash since it assumes wdev->cqm_config is set. This can't
be fixed with a simple non-NULL check since there's nothing
we can do for locking easily, so use RCU instead to protect
the pointer, but that requires pulling the updates out into
an asynchronous worker so they can sleep and call back into
the driver.

Since we need to change the free anyway, also change it to
go back to the old settings if changing the settings fails.

Reported-and-tested-by: Max Schulze <max.schulze@online.de>
Closes: https://lore.kernel.org/r/ac96309a-8d8d-4435-36e6-6d152eb31876@online.de
Fixes: 4a4b8169501b ("cfg80211: Accept multiple RSSI thresholds for CQM")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10 22:00:40 +02:00
Johannes Berg
3fcc6d7d5f wifi: cfg80211: add a work abstraction with special semantics
[ Upstream commit a3ee4dc84c4e9d14cb34dad095fd678127aca5b6 ]

Add a work abstraction at the cfg80211 level that will always
hold the wiphy_lock() for any work executed and therefore also
can be canceled safely (without waiting) while holding that.
This improves on what we do now as with the new wiphy works we
don't have to worry about locking while cancelling them safely.

Also, don't let such works run while the device is suspended,
since they'll likely need to interact with the device. Flush
them before suspend though.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Stable-dep-of: 37c20b2effe9 ("wifi: cfg80211: fix cqm_config access race")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10 22:00:39 +02:00
Florian Westphal
1e4c03d530 netfilter: nf_tables: fix kdoc warnings after gc rework
commit 08713cb006b6f07434f276c5ee214fb20c7fd965 upstream.

Jakub Kicinski says:
  We've got some new kdoc warnings here:
  net/netfilter/nft_set_pipapo.c:1557: warning: Function parameter or member '_set' not described in 'pipapo_gc'
  net/netfilter/nft_set_pipapo.c:1557: warning: Excess function parameter 'set' description in 'pipapo_gc'
  include/net/netfilter/nf_tables.h:577: warning: Function parameter or member 'dead' not described in 'nft_set'

Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Closes: https://lore.kernel.org/netdev/20230810104638.746e46f1@kernel.org/
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-06 14:57:02 +02:00
Florian Westphal
7e5d732e69 netfilter: nf_tables: fix memleak when more than 255 elements expired
commit cf5000a7787cbc10341091d37245a42c119d26c5 upstream.

When more than 255 elements expired we're supposed to switch to a new gc
container structure.

This never happens: u8 type will wrap before reaching the boundary
and nft_trans_gc_space() always returns true.

This means we recycle the initial gc container structure and
lose track of the elements that came before.

While at it, don't deref 'gc' after we've passed it to call_rcu.

Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06 14:56:35 +02:00
Pablo Neira Ayuso
8c643a8e04 netfilter: nft_set_pipapo: call nft_trans_gc_queue_sync() in catchall GC
commit 4a9e12ea7e70223555ec010bec9f711089ce96f6 upstream.

pipapo needs to enqueue GC transactions for catchall elements through
nft_trans_gc_queue_sync(). Add nft_trans_gc_catchall_sync() and
nft_trans_gc_catchall_async() to handle GC transaction queueing
accordingly.

Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06 14:56:35 +02:00
Florian Westphal
a42ac74c96 netfilter: nf_tables: defer gc run if previous batch is still pending
commit 8e51830e29e12670b4c10df070a4ea4c9593e961 upstream.

Don't queue more gc work, else we may queue the same elements multiple
times.

If an element is flagged as dead, this can mean that either the previous
gc request was invalidated/discarded by a transaction or that the previous
request is still pending in the system work queue.

The latter will happen if the gc interval is set to a very low value,
e.g. 1ms, and system work queue is backlogged.

The sets refcount is 1 if no previous gc requeusts are queued, so add
a helper for this and skip gc run if old requests are pending.

Add a helper for this and skip the gc run in this case.

Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06 14:56:34 +02:00
Pablo Neira Ayuso
0b9af4860a netfilter: nf_tables: remove busy mark and gc batch API
commit a2dd0233cbc4d8a0abb5f64487487ffc9265beb5 upstream.

Ditch it, it has been replace it by the GC transaction API and it has no
clients anymore.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06 14:56:33 +02:00
Pablo Neira Ayuso
ea3eb9f219 netfilter: nf_tables: GC transaction API to avoid race with control plane
commit 5f68718b34a531a556f2f50300ead2862278da26 upstream.

The set types rhashtable and rbtree use a GC worker to reclaim memory.
From system work queue, in periodic intervals, a scan of the table is
done.

The major caveat here is that the nft transaction mutex is not held.
This causes a race between control plane and GC when they attempt to
delete the same element.

We cannot grab the netlink mutex from the work queue, because the
control plane has to wait for the GC work queue in case the set is to be
removed, so we get following deadlock:

   cpu 1                                cpu2
     GC work                            transaction comes in , lock nft mutex
       `acquire nft mutex // BLOCKS
                                        transaction asks to remove the set
                                        set destruction calls cancel_work_sync()

cancel_work_sync will now block forever, because it is waiting for the
mutex the caller already owns.

This patch adds a new API that deals with garbage collection in two
steps:

1) Lockless GC of expired elements sets on the NFT_SET_ELEM_DEAD_BIT
   so they are not visible via lookup. Annotate current GC sequence in
   the GC transaction. Enqueue GC transaction work as soon as it is
   full. If ruleset is updated, then GC transaction is aborted and
   retried later.

2) GC work grabs the mutex. If GC sequence has changed then this GC
   transaction lost race with control plane, abort it as it contains
   stale references to objects and let GC try again later. If the
   ruleset is intact, then this GC transaction deactivates and removes
   the elements and it uses call_rcu() to destroy elements.

Note that no elements are removed from GC lockless path, the _DEAD bit
is set and pointers are collected. GC catchall does not remove the
elements anymore too. There is a new set->dead flag that is set on to
abort the GC transaction to deal with set->ops->destroy() path which
removes the remaining elements in the set from commit_release, where no
mutex is held.

To deal with GC when mutex is held, which allows safe deactivate and
removal, add sync GC API which releases the set element object via
call_rcu(). This is used by rbtree and pipapo backends which also
perform garbage collection from control plane path.

Since element removal from sets can happen from control plane and
element garbage collection/timeout, it is necessary to keep the set
structure alive until all elements have been deactivated and destroyed.

We cannot do a cancel_work_sync or flush_work in nft_set_destroy because
its called with the transaction mutex held, but the aforementioned async
work queue might be blocked on the very mutex that nft_set_destroy()
callchain is sitting on.

This gives us the choice of ABBA deadlock or UaF.

To avoid both, add set->refs refcount_t member. The GC API can then
increment the set refcount and release it once the elements have been
free'd.

Set backends are adapted to use the GC transaction API in a follow up
patch entitled:

  ("netfilter: nf_tables: use gc transaction API in set backends")

This is joint work with Florian Westphal.

Fixes: cfed7e1b1f8e ("netfilter: nf_tables: add set garbage collection helpers")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06 14:56:33 +02:00
Kuniyuki Iwashima
63830afece tcp: Fix bind() regression for v4-mapped-v6 wildcard address.
[ Upstream commit aa99e5f87bd54db55dd37cb130bd5eb55933027f ]

Andrei Vagin reported bind() regression with strace logs.

If we bind() a TCPv6 socket to ::FFFF:0.0.0.0 and then bind() a TCPv4
socket to 127.0.0.1, the 2nd bind() should fail but now succeeds.

  from socket import *

  s1 = socket(AF_INET6, SOCK_STREAM)
  s1.bind(('::ffff:0.0.0.0', 0))

  s2 = socket(AF_INET, SOCK_STREAM)
  s2.bind(('127.0.0.1', s1.getsockname()[1]))

During the 2nd bind(), if tb->family is AF_INET6 and sk->sk_family is
AF_INET in inet_bind2_bucket_match_addr_any(), we still need to check
if tb has the v4-mapped-v6 wildcard address.

The example above does not work after commit 5456262d2baa ("net: Fix
incorrect address comparison when searching for a bind2 bucket"), but
the blamed change is not the commit.

Before the commit, the leading zeros of ::FFFF:0.0.0.0 were treated
as 0.0.0.0, and the sequence above worked by chance.  Technically, this
case has been broken since bhash2 was introduced.

Note that if we bind() two sockets to 127.0.0.1 and then ::FFFF:0.0.0.0,
the 2nd bind() fails properly because we fall back to using bhash to
detect conflicts for the v4-mapped-v6 address.

Fixes: 28044fc1d495 ("net: Add a bhash2 table hashed by port and address")
Reported-by: Andrei Vagin <avagin@google.com>
Closes: https://lore.kernel.org/netdev/ZPuYBOFC8zsK6r9T@google.com/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-19 12:28:10 +02:00