linux-stable.git/net, branch v6.7.2

ipv6: mcast: fix data-race in ipv6_mc_down / mld_ifc_work

2024-01-25T23:45:31+00:00

[ Upstream commit 2e7ef287f07c74985f1bf2858bedc62bd9ebf155 ]

idev->mc_ifc_count can be written over without proper locking.

Originally found by syzbot [1], fix this issue by encapsulating calls
to mld_ifc_stop_work() (and mld_gq_stop_work() for good measure) with
mutex_lock() and mutex_unlock() accordingly as these functions
should only be called with mc_lock per their declarations.

[1]
BUG: KCSAN: data-race in ipv6_mc_down / mld_ifc_work

write to 0xffff88813a80c832 of 1 bytes by task 3771 on cpu 0:
 mld_ifc_stop_work net/ipv6/mcast.c:1080 [inline]
 ipv6_mc_down+0x10a/0x280 net/ipv6/mcast.c:2725
 addrconf_ifdown+0xe32/0xf10 net/ipv6/addrconf.c:3949
 addrconf_notify+0x310/0x980
 notifier_call_chain kernel/notifier.c:93 [inline]
 raw_notifier_call_chain+0x6b/0x1c0 kernel/notifier.c:461
 __dev_notify_flags+0x205/0x3d0
 dev_change_flags+0xab/0xd0 net/core/dev.c:8685
 do_setlink+0x9f6/0x2430 net/core/rtnetlink.c:2916
 rtnl_group_changelink net/core/rtnetlink.c:3458 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3717 [inline]
 rtnl_newlink+0xbb3/0x1670 net/core/rtnetlink.c:3754
 rtnetlink_rcv_msg+0x807/0x8c0 net/core/rtnetlink.c:6558
 netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2545
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6576
 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
 netlink_unicast+0x589/0x650 net/netlink/af_netlink.c:1368
 netlink_sendmsg+0x66e/0x770 net/netlink/af_netlink.c:1910
 ...

write to 0xffff88813a80c832 of 1 bytes by task 22 on cpu 1:
 mld_ifc_work+0x54c/0x7b0 net/ipv6/mcast.c:2653
 process_one_work kernel/workqueue.c:2627 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2700
 worker_thread+0x525/0x730 kernel/workqueue.c:2781
 ...

Fixes: 2d9a93b4902b ("mld: convert from timer to delayed work")
Reported-by: syzbot+a9400cabb1d784e49abf@syzkaller.appspotmail.com
Link: https://lore.kernel.org/all/000000000000994e09060ebcdffb@google.com/
Signed-off-by: Nikita Zhandarovich 
Acked-by: Taehee Yoo 
Reviewed-by: Eric Dumazet 
Reviewed-by: Hangbin Liu 
Link: https://lore.kernel.org/r/20240117172102.12001-1-n.zhandarovich@fintech.ru
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

ethtool: netlink: Add missing ethnl_ops_begin/complete

2024-01-25T23:45:30+00:00

[ Upstream commit f1172f3ee3a98754d95b968968920a7d03fdebcc ]

Accessing an ethernet device that is powered off or clock gated might
cause the CPU to hang. Add ethnl_ops_begin/complete in
ethnl_set_features() to protect against this.

Fixes: 0980bfcd6954 ("ethtool: set netdev features with FEATURES_SET request")
Signed-off-by: Ludvig Pärsson 
Link: https://lore.kernel.org/r/20240117-etht2-v2-1-1a96b6e8c650@axis.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

ipvs: avoid stat macros calls from preemptible context

2024-01-25T23:45:30+00:00

[ Upstream commit d6938c1c76c64f42363d0d1f051e1b4641c2ad40 ]

Inside decrement_ttl() upon discovering that the packet ttl has exceeded,
__IP_INC_STATS and __IP6_INC_STATS macros can be called from preemptible
context having the following backtrace:

check_preemption_disabled: 48 callbacks suppressed
BUG: using __this_cpu_add() in preemptible [00000000] code: curl/1177
caller is decrement_ttl+0x217/0x830
CPU: 5 PID: 1177 Comm: curl Not tainted 6.7.0+ #34
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 04/01/2014
Call Trace:
 
 dump_stack_lvl+0xbd/0xe0
 check_preemption_disabled+0xd1/0xe0
 decrement_ttl+0x217/0x830
 __ip_vs_get_out_rt+0x4e0/0x1ef0
 ip_vs_nat_xmit+0x205/0xcd0
 ip_vs_in_hook+0x9b1/0x26a0
 nf_hook_slow+0xc2/0x210
 nf_hook+0x1fb/0x770
 __ip_local_out+0x33b/0x640
 ip_local_out+0x2a/0x490
 __ip_queue_xmit+0x990/0x1d10
 __tcp_transmit_skb+0x288b/0x3d10
 tcp_connect+0x3466/0x5180
 tcp_v4_connect+0x1535/0x1bb0
 __inet_stream_connect+0x40d/0x1040
 inet_stream_connect+0x57/0xa0
 __sys_connect_file+0x162/0x1a0
 __sys_connect+0x137/0x160
 __x64_sys_connect+0x72/0xb0
 do_syscall_64+0x6f/0x140
 entry_SYSCALL_64_after_hwframe+0x6e/0x76
RIP: 0033:0x7fe6dbbc34e0

Use the corresponding preemption-aware variants: IP_INC_STATS and
IP6_INC_STATS.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 8d8e20e2d7bb ("ipvs: Decrement ttl")
Signed-off-by: Fedor Pchelkin 
Acked-by: Julian Anastasov 
Acked-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_tables: reject NFT_SET_CONCAT with not field length description

2024-01-25T23:45:30+00:00

[ Upstream commit 113661e07460a6604aacc8ae1b23695a89e7d4b3 ]

It is still possible to set on the NFT_SET_CONCAT flag by specifying a
set size and no field description, report EINVAL in such case.

Fixes: 1b6345d4160e ("netfilter: nf_tables: check NFT_SET_CONCAT flag if field_count is specified")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_tables: skip dead set elements in netlink dump

2024-01-25T23:45:30+00:00

[ Upstream commit 6b1ca88e4bb63673dc9f9c7f23c899f22c3cb17a ]

Delete from packet path relies on the garbage collector to purge
elements with NFT_SET_ELEM_DEAD_BIT on.

Skip these dead elements from nf_tables_dump_setelem() path, I very
rarely see tests/shell/testcases/maps/typeof_maps_add_delete reports
[DUMP FAILED] showing a mismatch in the expected output with an element
that should not be there.

If the netlink dump happens before GC worker run, it might show dead
elements in the ruleset listing.

nft_rhash_get() already skips dead elements in nft_rhash_cmp(),
therefore, it already does not show the element when getting a single
element via netlink control plane.

Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_tables: do not allow mismatch field size and set key length

2024-01-25T23:45:30+00:00

[ Upstream commit 3ce67e3793f48c1b9635beb9bb71116ca1e51b58 ]

The set description provides the size of each field in the set whose sum
should not mismatch the set key length, bail out otherwise.

I did not manage to crash nft_set_pipapo with mismatch fields and set key
length so far, but this is UB which must be disallowed.

Fixes: f3a2181e16f1 ("netfilter: nf_tables: Support for sets with multiple ranged fields")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: bridge: replace physindev with physinif in nf_bridge_info

2024-01-25T23:45:30+00:00

[ Upstream commit 9874808878d9eed407e3977fd11fee49de1e1d86 ]

An skb can be added to a neigh->arp_queue while waiting for an arp
reply. Where original skb's skb->dev can be different to neigh's
neigh->dev. For instance in case of bridging dnated skb from one veth to
another, the skb would be added to a neigh->arp_queue of the bridge.

As skb->dev can be reset back to nf_bridge->physindev and used, and as
there is no explicit mechanism that prevents this physindev from been
freed under us (for instance neigh_flush_dev doesn't cleanup skbs from
different device's neigh queue) we can crash on e.g. this stack:

arp_process
  neigh_update
    skb = __skb_dequeue(&neigh->arp_queue)
      neigh_resolve_output(..., skb)
        ...
          br_nf_dev_xmit
            br_nf_pre_routing_finish_bridge_slow
              skb->dev = nf_bridge->physindev
              br_handle_frame_finish

Let's use plain ifindex instead of net_device link. To peek into the
original net_device we will use dev_get_by_index_rcu(). Thus either we
get device and are safe to use it or we don't get it and drop skb.

Fixes: c4e70a87d975 ("netfilter: bridge: rename br_netfilter.c to br_netfilter_hooks.c")
Suggested-by: Florian Westphal 
Signed-off-by: Pavel Tikhomirov 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: propagate net to nf_bridge_get_physindev

2024-01-25T23:45:29+00:00

[ Upstream commit a54e72197037d2c9bfcd70dddaac8c8ccb5b41ba ]

This is a preparation patch for replacing physindev with physinif on
nf_bridge_info structure. We will use dev_get_by_index_rcu to resolve
device, when needed, and it requires net to be available.

Signed-off-by: Pavel Tikhomirov 
Reviewed-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso 
Stable-dep-of: 9874808878d9 ("netfilter: bridge: replace physindev with physinif in nf_bridge_info")
Signed-off-by: Sasha Levin

netfilter: nf_queue: remove excess nf_bridge variable

2024-01-25T23:45:29+00:00

[ Upstream commit aeaa44075f8e49e2e0ad4507d925e690b7950145 ]

We don't really need nf_bridge variable here. And nf_bridge_info_exists
is better replacement for nf_bridge_info_get in case we are only
checking for existence.

Signed-off-by: Pavel Tikhomirov 
Reviewed-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso 
Stable-dep-of: 9874808878d9 ("netfilter: bridge: replace physindev with physinif in nf_bridge_info")
Signed-off-by: Sasha Levin

netfilter: nfnetlink_log: use proper helper for fetching physinif

2024-01-25T23:45:29+00:00

[ Upstream commit c3f9fd54cd87233f53bdf0e191a86b3a5e960e02 ]

We don't use physindev in __build_packet_message except for getting
physinif from it. So let's switch to nf_bridge_get_physinif to get what
we want directly.

Signed-off-by: Pavel Tikhomirov 
Reviewed-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso 
Stable-dep-of: 9874808878d9 ("netfilter: bridge: replace physindev with physinif in nf_bridge_info")
Signed-off-by: Sasha Levin