When a timer is deleted and not re-armed in igmp_mod_timer(), or stopped
in igmp_stop_timer(), the code currently decrements the reference counter
of the multicast list entry @im using refcount_dec(&im->refcnt).
However, both functions can be called from the RCU reader path:
- igmp_mod_timer() via igmp_heard_query() -> for_each_pmc_rcu()
- igmp_stop_timer() via igmp_rcv() -> igmp_heard_report()
If the group im was concurrently removed from the list by ip_mc_dec_group(),
its reference count might have already been decremented to 1.
In this case, timer_delete() succeeds, and refcount_dec() decrements
the refcount from 1 to 0. Since refcount_dec() does not free the object
when it hits 0 (unlike ip_ma_put()), the im structure is leaked.
Fix this by using ip_ma_put(im) instead of refcount_dec(&im->refcnt),
and deferring the put until after the spinlock is released.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260705181756.963063-4-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
A race condition exists between device teardown (inetdev_destroy) and
incoming IGMP query processing (igmp_rcv), leading to a Use-After-Free
in the IGMP timer callback.
During device destruction, inetdev_destroy() drops the primary reference
to in_device, which can drop its refcount to 0. The actual freeing of
in_device memory is deferred via RCU (using call_rcu()).
Concurrently, igmp_rcv() runs under RCU read lock and obtains the
in_device pointer. Because the memory is RCU-protected, CPU-0 can safely
dereference in_device even if its refcount has hit 0.
However, if CPU-0 calls igmp_gq_start_timer() and re-arms the timer, it
attempts to acquire a reference using in_dev_hold(). This increments the
refcount from 0 to 1, triggering a "refcount_t: addition on 0" warning.
Since the in_device memory is still scheduled to be freed after the RCU
grace period (as the free callback does not check the refcount again),
the device is freed while the timer is still armed. When the timer
expires, it accesses the freed memory, causing a kernel panic.
Fix this by using refcount_inc_not_zero() (via a new helper
in_dev_hold_safe()) to prevent acquiring a reference if the device is
already being destroyed. If the refcount is 0, we do not arm the timer.
A similar issue in IPv6 MLD is fixed in a subsequent patch.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: Zero Day Initiative <zdi-disclosures@trendmicro.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260705181756.963063-2-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When a device is destroyed under RTNL, ip_mc_destroy_dev() iterates through
the multicast list and calls ip_ma_put() on each membership, scheduling
them for RCU reclamation. However, they are not unlinked from the device's
multicast hash table (mc_hash).
Since the device remains published in dev->ip_ptr until after
ip_mc_destroy_dev() completes, concurrent RCU readers traversing mc_hash
can still locate and access the multicast group after its refcount is
decremented. If the RCU callback runs and frees the group while a reader is
accessing it, a use-after-free occurs.
Fix this by unlinking the multicast group from mc_hash using
ip_mc_hash_remove() before scheduling it for reclamation.
BUG: KASAN: slab-use-after-free in ip_check_mc_rcu+0x149/0x3f0
Read of size 4 at addr ffff888009bf1408 by task mausezahn/2276
Call Trace:
<IRQ>
dump_stack_lvl+0x67/0x90
print_report+0x175/0x7c0
kasan_report+0x147/0x180
ip_check_mc_rcu+0x149/0x3f0
udp_v4_early_demux+0x36d/0x12d0
ip_rcv_finish_core+0xb8b/0x1390
ip_rcv_finish+0x54/0x120
NF_HOOK+0x213/0x2b0
__netif_receive_skb+0x126/0x340
process_backlog+0x4f2/0xf00
__napi_poll+0x92/0x2c0
net_rx_action+0x583/0xc60
handle_softirqs+0x236/0x7f0
do_softirq+0x57/0x80
</IRQ>
Allocated by task 2239:
kasan_save_track+0x3e/0x80
__kasan_kmalloc+0x72/0x90
____ip_mc_inc_group+0x31a/0xa40
__ip_mc_join_group+0x334/0x3f0
do_ip_setsockopt+0x16fa/0x2010
ip_setsockopt+0x3f/0x90
do_sock_setsockopt+0x1ad/0x300
Freed by task 0:
kasan_save_track+0x3e/0x80
kasan_save_free_info+0x40/0x50
__kasan_slab_free+0x3a/0x60
__rcu_free_sheaf_prepare+0xd4/0x220
rcu_free_sheaf+0x36/0x190
rcu_core+0x8d9/0x12f0
handle_softirqs+0x236/0x7f0
Fixes: e989707135 ("igmp: hash a hash table to speedup ip_check_mc_rcu()")
Cc: stable@vger.kernel.org
Signed-off-by: Yuyang Huang <yuyanghuang@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260701235014.73505-1-yuyanghuang@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When CONFIG_IP_MULTIPLE_TABLES is disabled, fib_new_table()
is fib_get_table(), and no new table is created.
Let's move net->ipv4.fib_table_hash_lock under
CONFIG_IP_MULTIPLE_TABLES.
While at it, netns_ipv4_sysctl.rst is updated.
Suggested-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260702044437.591864-2-kuniyu@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Merge tag 'nf-next-26-07-02' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next
Florian Westphal says:
====================
netfilter: updates for net-next
The following patchset contains Netfilter updates for *net-next*.
1) Update nfnetlink_hook to dump the individual NAT type chains
instead of the nat base chains to userspace. From Phil Sutter.
2) Replace strlcpy/strlcat() with snprintf() in x_tables, from Ian Bridges.
3) Start replacing u_int8_t and u_int16t with u8 and u16 in netfilter.
From Carlos Grillet.
4) Replace strcpy() with strscpy() in netfilter, from David Laight.
5) Remove redundant NULL check before kvfree().
6) Add parameter validation to xt_tcpmss. Ensure mss_min <= mss_max and
invert <= 1. From Feng Wu.
7) Add checkentry for xt_dscp 'tos' match. Implement tos_mt_check() to reject
invalid invert values. Also from Feng Wu.
8) Stop hashing nf_conntrack_helper by tuple. Switch to hashing by name and
L4 protocol.
9) Remove tuples from conntrack helper definitions and port usage from
broadcast helpers. Add netlink policy validation to prevent protocol
number truncation.
10) Remove obsolete netfilter conntrack module parameters.
11) Bound num_counters in ebtables: do_replace() by MAX_EBT_ENTRIES to prevent
oversized vmalloc_array() allocations. From Jiayuan Chen.
12) Make expectations created via nft_ct rules work with NAT.
netfilter pull request nf-next-26-07-02
* tag 'nf-next-26-07-02' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
netfilter: nft_ct: support expectation creation for natted flows
netfilter: ebtables: bound num_counters like nentries in do_replace()
netfilter: conntrack: remove obsolete module parameters
netfilter: conntrack: get rid of tuple in helper definitions
netfilter: nf_conntrack_helper: do not hash by tuple
netfilter: xt_dscp: add checkentry for tos match
netfilter: xt_tcpmss: add checkentry for parameter validation
netfilter: remove redundant null check before kvfree()
netfilter: avoid strcpy usage
netfilter: replace u_int8_t and u_int16t with u8 and u16
netfilter: x_tables: replace strlcat() with snprintf()
netfilter: nfnetlink_hook: Dump nat type chains
====================
Link: https://patch.msgid.link/20260702105003.13550-1-fw@strlen.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
RTM_GETMULTICAST has been part of the rtnetlink ABI for a long time
and already reports IPv4 multicast group membership through
IFA_MULTICAST and IFA_CACHEINFO. It does not report how many consumers
hold each membership, so userspace still has to parse /proc/net/igmp to
get the Users column.
Add IFA_MC_USERS as a u32 attribute carrying ip_mc_list::users in
RTM_GETMULTICAST replies and entry-lifecycle notifications.
This gives iproute2 enough information to migrate the IPv4 part of
"ip maddr show" from procfs parsing to rtnetlink.
Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260630110207.37841-2-sigefriedhyy@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
inet_dump_fib() saves its progress in cb->args[1] as a positional
index within the current hash chain. Between batches, a concurrent
fib_new_table() can insert a new table at the chain head, shifting
all existing entries. On resume the saved index lands on a different
table, causing already-dumped tables to be re-dumped and the
originally suspended table to restart from the beginning.
Fix by storing tb->tb_id in cb->args[1] instead of a positional
index, mirroring the fix applied to inet6_dump_fib() in commit
9facb861dc ("ipv6: fib6: fix NULL deref in fib6_walk_continue()
on multi-batch dump").
Signed-off-by: Pengfei Zhang <zhangfeionline@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260630084220.2711025-1-zhangfeionline@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Cross-merge networking fixes after downstream PR (net-7.2-rc2).
No conflicts.
Adjacent changes:
MAINTAINERS:
56114690ff ("MAINTAINERS: Update Marvell octeontx2 driver maintainers")
eb56577ae9 ("ehea: remove the ehea driver")
net/core/netpoll.c:
45f1458a85 ("netpoll: fix a use-after-free on shutdown path")
84c0ff1efb ("netpoll: do not warn when the best-effort pool refill fails")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Continue converting the proto-layer getsockopt callbacks to the sockopt_t
interface, switching do_raw_getsockopt() and its raw_geticmpfilter()
helper to take a sockopt_t.
The thin raw_getsockopt() wrapper keeps its __user signature for now: it
builds a user-backed sockopt_t with sockopt_init_user(), calls the helper,
and writes the returned length back to optlen. The helper uses
copy_to_iter() instead of copy_to_user(). No functional change.
Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Acked-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260630-getsockopt_phase2-v2-3-193335f3d4d1@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
In preparation for converting the proto-layer getsockopt callbacks to the
sockopt_t interface, switch udp_lib_getsockopt() to take a sockopt_t.
The thin udp_getsockopt()/udpv6_getsockopt() wrappers keep their __user
signature for now: they build a user-backed sockopt_t with
sockopt_init_user(), call the helper, and write the returned length back
to optlen. The helper uses copy_to_iter() instead of copy_to_user().
No functional change.
Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Acked-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260630-getsockopt_phase2-v2-2-193335f3d4d1@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Now, RTM_DELRULE no longer needs RTNL, and the only RTNL dependant
in RTM_NEWRULE is fib_unmerge(), which is called for the first
IPv4 rule.
Let's add fib_rules_ops.need_rtnl() and hold RTNL only for the
first IPv4 rule.
Tested:
The script below creates 1K rules in parallel in 4K netns, and
it got 20x/30x faster for IPv4/IPv6.
#!/bin/bash
N=4096
F=rules.txt
for i in $(seq $N); do ip netns add ns-$i; done
printf 'rule add from all table %d\n' {1..1024} > $F
for v in 4 6; do
echo "=== IPv${v} ==="
time { for i in $(seq $N); do nsenter \
--net=/var/run/netns/ns-$i ip -$v -batch $F & done; wait; }
done
for i in $(seq $N); do ip netns del ns-$i; done
rm -f $F
Without this series:
# ./test.sh
=== IPv4 ===
real 0m22.752s
user 0m7.834s
sys 92m46.721s
=== IPv6 ===
real 0m35.181s
user 0m8.635s
sys 142m30.479s
With this series:
# ./test.sh
=== IPv4 ===
real 0m0.918s
user 0m5.675s
sys 2m7.024s
=== IPv6 ===
real 0m1.214s
user 0m7.917s
sys 4m19.489s
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260629181226.1929658-10-kuniyu@google.com
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
fib_newrule() will drop RTNL except for the first IPv4 rule.
net->ipv4.fib_table_hash[] will be read with no protection,
but this is fine because fib_table is not destroyed until
netns dismantle except for the merged main/local table.
fib_unmerge() will continue to be called under RTNL, so other
readers (fib_flush() and fib_info_notify_update()) just have
to care about the concurrent hlist_add().
IPv6 and IPMR/IP6MR also take this strategy and use RCU helpers
to avoid data race against concurrent hlist_add().
Let's not use lockdep_rtnl_is_held() and rcu_dereference_rtnl()
for net->ipv4.fib_table_hash[].
Note that commit a7e5353123 ("fib_trie: Make fib_table rcu
safe") started to use the _safe version in fib_flush(), but it
is not needed thanks to RTNL.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260629181226.1929658-5-kuniyu@google.com
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
fib_newrule() will drop RTNL except for the first IPv4 rule.
Then, fib4_rule_configure() could call fib_empty_table() and create
a new IPv4 fib_table without RTNL.
Currently, net->ipv4.fib_table_hash[] is only protected by RTNL.
As a prep, let's protect net->ipv4.fib_table_hash[] with a dedicated
spinlock.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260629181226.1929658-4-kuniyu@google.com
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
IPv4 local and main route tables are merged by default to avoid
unnecessary rule lookups.
When the first IPv4 rule is created, fib_unmerge() splits the
two tables.
However, fib4_rule_configure() currently always calls fib_unmerge(),
and even fetching a table via fib_get_table() requires RTNL (or RCU).
We will drop RTNL from fib_newrule() if not needed.
Let's call fib_unmerge() only once for the first rule.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260629181226.1929658-3-kuniyu@google.com
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Since commit d954a67a7d ("ipv4: fib_rule: Move fib4_rules_exit()
to ->exit()."), both fib4_rule_delete() and fib6_rule_delete() always
return 0.
Let's change the return type to void.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260629181226.1929658-2-kuniyu@google.com
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
In case of early freeing an unwanted TCP-MD5 key on TCP-AO connect(),
md5sig_info is freed right away (and set to NULL). Later, at
the moment of socket destruction, the static branch counter
is not getting decremented.
Add a missing decrement for TCP-MD5 static branch.
Reported-by: Qihang <q.h.hack.winter@gmail.com>
Fixes: 0aadc73995 ("net/tcp: Prevent TCP-MD5 with TCP-AO being set")
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com>
Link: https://patch.msgid.link/20260625-tcp-md5-connect-v3-3-1fd313d6c1e0@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The md5+ao reconciliation in tcp_connect() (net/ipv4/tcp_output.c)
has two symmetric branches:
if (needs_md5) {
tcp_ao_destroy_sock(sk, false);
} else if (needs_ao) {
tcp_clear_md5_list(sk);
kfree(rcu_replace_pointer(tp->md5sig_info, NULL, ...));
}
Both branches free a per-socket auth-info object while the socket is
in TCP_SYN_SENT and is already on the inet ehash (inserted by
inet_hash_connect() in tcp_v4_connect()). Both branches are reachable
by softirq RX-path readers that load the corresponding info pointer
via implicit RCU before bh_lock_sock_nested() is taken.
The needs_md5 branch is fixed in the prior patch by re-introducing
the call_rcu() free in tcp_ao_destroy_sock(): the equivalent per-key
loop runs inside tcp_ao_info_free_rcu(), the RCU callback, so by the
time it frees each tcp_ao_key all softirq readers that captured the
container have already completed rcu_read_unlock().
The needs_ao branch is not symmetric in the same way. The container
free can be deferred via kfree_rcu(md5sig, rcu) -- struct
tcp_md5sig_info already has the required rcu member
(include/net/tcp.h:1999-2002), and the rest of the tree already does
this in the tcp_md5sig_info_add() rollback paths
(net/ipv4/tcp_ipv4.c:1410, 1436). But the per-key teardown is done
by tcp_clear_md5_list() in process context BEFORE the container's
RCU grace period: it walks &md5sig->head and frees each
tcp_md5sig_key with bare hlist_del + kfree. A concurrent softirq
reader in __tcp_md5_do_lookup() / __tcp_md5_do_lookup_exact()
(tcp_ipv4.c:1253, 1298) walks the same list via
hlist_for_each_entry_rcu() and races with that bare kfree on the
keys themselves -- a per-key slab use-after-free of the same class
as the TCP-AO bug, on the same race window.
Fix this in two halves:
1. Convert the bare kfree() in tcp_connect() to kfree_rcu() so the
md5sig_info container joins the rest of the md5sig lifecycle.
The local-variable lift is mechanical and required because
kfree_rcu() is a macro that expects an lvalue.
2. Make tcp_clear_md5_list() RCU-safe by replacing hlist_del +
kfree(key) with hlist_del_rcu + kfree_rcu(key, rcu). struct
tcp_md5sig_key already carries the rcu member
(include/net/tcp.h:1995) and tcp_md5_do_del()
(net/ipv4/tcp_ipv4.c:1456) already uses kfree_rcu, so this
restores the lifecycle invariant the rest of the file follows
rather than introducing a one-off.
The other caller of tcp_clear_md5_list() is tcp_md5_destruct_sock()
(net/ipv4/tcp.c:412), which runs from the sock destructor when the
socket is already unhashed and unreachable; the extra grace period
there is unnecessary but harmless. Making the helper unconditionally
RCU-safe is the cleaner contract.
The needs_ao branch is not reachable by the userns reproducer used
to demonstrate the AO-side splat (the repro installs both keys but
ends up in the needs_md5 branch because the connect peer matches
the MD5 key, not the AO key); however the symmetric race exists
and a maintainer touching this code should not have to think about
which branch escapes RCU and which one does not.
Fixes: 51e547e8c8 ("tcp: Free TCP-AO/TCP-MD5 info/keys without RCU")
Cc: stable@vger.kernel.org # v6.18+
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Reviewed-by: Dmitry Safonov <dima@arista.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
[also credits to Qihang, who found that this races with tcp-diag]
Reported-by: Qihang <q.h.hack.winter@gmail.com>
Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com>
Link: https://patch.msgid.link/20260625-tcp-md5-connect-v3-2-1fd313d6c1e0@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit 51e547e8c8 ("tcp: Free TCP-AO/TCP-MD5 info/keys without RCU")
removed the call_rcu() callback from tcp_ao_destroy_sock(), arguing that
"the destruction of info/keys is delayed until the socket destructor"
and therefore "no one can discover it anymore".
That argument does not hold for the call site in tcp_connect()
(net/ipv4/tcp_output.c:4327-4332). At that point the socket is in
TCP_SYN_SENT, has already been inserted into the inet ehash by
inet_hash_connect() in tcp_v4_connect(), and is therefore very much
discoverable: any softirq running tcp_v4_rcv() on another CPU can take
the socket out of the ehash, walk into tcp_inbound_hash(), and load
tp->ao_info via implicit RCU before bh_lock_sock_nested() is taken on
the destroying CPU.
The reader path then enters __tcp_ao_do_lookup() (net/ipv4/tcp_ao.c:208)
which re-loads tp->ao_info via rcu_dereference_check(); the re-load can
still observe the (about-to-be-freed) pointer because there is no
synchronize_rcu() between rcu_assign_pointer(tp->ao_info, NULL) and
tcp_ao_info_free() in tcp_ao_destroy_sock(). The captured pointer is
then walked at line 223:
hlist_for_each_entry_rcu(key, &ao->head, node, ...)
The writer's synchronous kfree() is free to complete between the line
218 re-fetch and the line 223 hlist iteration. The slab is reused
(or simply LIST_POISON1-stamped if not yet reused) and the iteration
walks attacker-controlled or poison memory in softirq context.
Reproducer (no debug shim, stock x86_64 v7.1-rc2 SMP+KASAN, QEMU+KVM):
an unprivileged uid=1000 process inside CLONE_NEWUSER|CLONE_NEWNET
installs TCP_MD5SIG + TCP_AO_ADD_KEY on a TCP socket, sprays forged
TCP-AO segments toward its eventual 4-tuple via raw sockets, then
calls connect(). The md5-wins reconciliation in tcp_connect() fires
tcp_ao_destroy_sock(); the softirq backlog reader on the loopback
NAPI path crashes on the freed ao->head.first walk:
Oops: general protection fault, probably for non-canonical
address 0xfbd59c000000002f
KASAN: maybe wild-memory-access in range
[0xdead000000000178-0xdead00000000017f]
CPU: 0 UID: 1000 PID: 100 Comm: repro_userns
RIP: 0010:__tcp_ao_do_lookup+0x107/0x1c0
Call Trace: <IRQ>
__tcp_ao_do_lookup+0x107/0x1c0
tcp_ao_inbound_lookup.constprop.0+0x12a/0x200
tcp_inbound_ao_hash+0x5ea/0x1520
tcp_inbound_hash+0x7ce/0x1240
tcp_v4_rcv+0x1e7a/0x3e10
...
Restore the RCU grace period: re-add struct rcu_head to tcp_ao_info
and replace the synchronous tcp_ao_info_free() with a call_rcu()
callback. Readers that captured tp->ao_info before rcu_assign_pointer
NULLed it now see the object remain valid until rcu_read_unlock().
With the patch applied the reproducer runs cleanly for 2000 iterations
on the same kernel build.
Fixes: 51e547e8c8 ("tcp: Free TCP-AO/TCP-MD5 info/keys without RCU")
Cc: stable@vger.kernel.org # v6.18+
Reviewed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com>
Link: https://patch.msgid.link/20260625-tcp-md5-connect-v3-1-1fd313d6c1e0@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Current release - regressions:
- net: do not acquire dev->tx_global_lock in netdev_watchdog_up()
- net: ethtool: keep rtnl_lock for ops using ethtool_op_get_link()
- net: fix deadlock in nested UP notifier events
Current release - new code bugs:
- eth: cn20k: fix subbank free list indexing for search order
- eth: airoha: fix BQL underflow in shared QDMA TX ring
Previous releases - regressions:
- netfilter:
- flowtable: fix offloaded ct timeout never being extended
- nf_conncount: prevent connlimit drops for early confirmed ct
Previous releases - always broken:
- require CAP_NET_ADMIN in the originating netns when modifying
cross-netns devices
- report NAPI thread PID in the caller's pid namespace
- mac802154: fix dirty frag in in-place crypto for IOT radios
- sctp: hold socket lock when dumping endpoints in sctp_diag,
avoid an overflow
- eth: gve: fix header buffer corruption with header-split and HW-GRO
- af_key: initialize alg_key_len for IPComp states, prevent OOB read
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-7.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from netfilter and IPsec.
Current release - regressions:
- do not acquire dev->tx_global_lock in netdev_watchdog_up()
- ethtool: keep rtnl_lock for ops using ethtool_op_get_link()
- fix deadlock in nested UP notifier events
Current release - new code bugs:
- eth:
- cn20k: fix subbank free list indexing for search order
- airoha: fix BQL underflow in shared QDMA TX ring
Previous releases - regressions:
- netfilter:
- flowtable: fix offloaded ct timeout never being extended
- nf_conncount: prevent connlimit drops for early confirmed ct
Previous releases - always broken:
- require CAP_NET_ADMIN in the originating netns when modifying
cross-netns devices
- report NAPI thread PID in the caller's pid namespace
- mac802154: fix dirty frag in in-place crypto for IOT radios
- sctp: hold socket lock when dumping endpoints in sctp_diag, avoid
an overflow
- eth: gve: fix header buffer corruption with header-split and HW-GRO
- af_key: initialize alg_key_len for IPComp states, prevent OOB read"
* tag 'net-7.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (213 commits)
selftests: bonding: add a test for VLAN propagation over a bonded real device
vlan: defer real device state propagation to netdev_work
net: add the driver-facing netdev_work scheduling API
net: turn the rx_mode work into a generic netdev_work facility
net: ethtool: keep rtnl_lock for ops using ethtool_op_get_link()
rxrpc: Fix rxrpc_rotate_tx_rotate() to check there's something to rotate
rxrpc: Fix leak of released call in recvmsg(MSG_PEEK)
rxrpc: Fix socket notification race
rxrpc: Fix potential infinite loop in rxrpc_recvmsg()
rxrpc: Fix oob challenge leak in cleanup after notification failure
rxrpc: Fix the reception of a reply packet before data transmission
afs: Fix uncancelled rxrpc OOB message handler
afs: Fix further netns teardown to cancel the preallocation charger
rxrpc: Fix double unlock in rxrpc_recvmsg()
rxrpc: Fix leak of connection from OOB challenge
rxrpc: Fix ACKALL packet handling
net: hns3: differentiate autoneg default values between copper and fiber
net: hns3: fix permanent link down deadlock after reset
net: hns3: refactor MAC autoneg and speed configuration
net: hns3: unify copper port ksettings configuration path
...
Yue Sun reported a use-after-free and debugobjects warning in
udp_tunnel_nic_device_sync_work() during concurrent device operations.
The workqueue core clears the internal pending bit before invoking the
worker. At that point, a concurrent thread can queue the work again.
When the already running worker eventually clears the work_pending flag
to 0, it mistakenly clears the flag for the newly queued instance.
udp_tunnel_nic_unregister() then observes work_pending as 0 and frees
the structure while the second work item is still active in the queue,
leading to UAF.
Fix this by returning early in udp_tunnel_nic_device_sync() if
work_pending is already set, preventing redundant work queueing.
Fixes: cc4e3835ef ("udp_tunnel: add central NIC RX port offload infrastructure")
Reported-by: Yue Sun <samsun1006219@gmail.com>
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260625065938.654652-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In tcp_ao_delete_key(), the del_async path skips the current_key
and rnext_key validity checks present in the synchronous path,
assuming these pointers are always NULL on LISTEN sockets. However,
if a key was added with set_current=1/set_rnext=1 while the socket
was in CLOSE state, current_key and rnext_key will be non-NULL
after listen() transitions the socket to LISTEN.
When such a key is deleted with del_async=1, hlist_del_rcu() and
call_rcu() free the key without clearing the dangling pointers.
After the RCU grace period, getsockopt(TCP_AO_INFO) dereferences
current_key->sndid and rnext_key->rcvid from freed slab memory.
Clear current_key and rnext_key in the del_async path when they
reference the key being deleted.
Fixes: d6732b95b6 ("net/tcp: Allow asynchronous delete for TCP-AO keys (MKTs)")
Signed-off-by: HanQuan <eilaimemedsnaimel@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260623015208.1191687-1-eilaimemedsnaimel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'ipsec-2026-06-22' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:
====================
pull request (net): ipsec 2026-06-22
1) xfrm: use compat translator only for u64 alignment mismatch
Gate the XFRM_USER_COMPAT translator on COMPAT_FOR_U64_ALIGNMENT
so 32-bit compat tasks on arches whose 32-bit ABI already matches
the native 64-bit layout are no longer rejected with -EOPNOTSUPP.
From Sanman Pradhan.
2) net: af_key: initialize alg_key_len for IPComp states
Initialize the alg_key_len to 0 in the IPComp branch of
pfkey_msg2xfrm_state() so an uninitialized value cannot drive
xfrm_alg_len() into a slab-out-of-bounds kmemdup during
XFRM_MSG_MIGRATE. From Zijing Yin.
3) xfrm: Fix dev use-after-free in xfrm async resumption
Stash the original skb->dev and extend the RCU critical section
across xfrm_rcv_cb() and transport_finish() to prevent a
tunnel-device UAF and original-device refcount leak when a
callback replaces skb->dev. From Dong Chenchen.
4) xfrm: Fix xfrm state cache insertion race
Move the state-validity check inside xfrm_state_lock in the
input state cache insertion path so a state cannot be killed
between the check and the insert. From Herbert Xu.
5) xfrm: annotate data-races around xfrm_policy_count[] and xfrm_policy_default[]
Add READ_ONCE()/WRITE_ONCE() annotations on xfrm_policy_count
and xfrm_policy_default to silence the KCSAN data race reported
on net->xfrm.policy_count. From Eric Dumazet.
6) espintcp: use sk_msg_free_partial to fix partial send
Replace the manual skmsg accounting in espintcp with
sk_msg_free_partial() so the skmsg stays consistent on every
iteration and the partial-send accounting bugs go away.
From Sabrina Dubroca.
7) xfrm: validate selector family and prefixlen during match
Reject mismatched address families in xfrm_selector_match() and
bound prefixlen in addr4_match()/addr_match() to prevent the
shift-out-of-bounds syzbot reported when an AF_UNSPEC selector
with a large prefixlen is matched against an IPv4 flow.
From Eric Dumazet.
* tag 'ipsec-2026-06-22' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec:
xfrm: validate selector family and prefixlen during match
espintcp: use sk_msg_free_partial to fix partial send
xfrm: annotate data-races around xfrm_policy_count[] and xfrm_policy_default[]
xfrm: Fix xfrm state cache insertion race
xfrm: Fix dev use-after-free in xfrm async resumption
net: af_key: initialize alg_key_len for IPComp states
xfrm: use compat translator only for u64 alignment mismatch
====================
Link: https://patch.msgid.link/20260622075726.29685-1-steffen.klassert@secunet.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'nf-26-06-21' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for net. This batches
fixes for real crashes with trivial/correctness fixes. There is too
a rework of the conntrack expectation timeout strategy to deal with
a possible race when removing an expectation.
1) Fix the incorrect flowtable timeout extension for entries in
hw offload, from Adrian Bente. This is correcting a defect in
the functionality, no crash.
2) Hold reference to device under the fake dst in br_netfilter,
from Haoze Xie. This is fixing a possible UaF if the device
is removed while packet is sitting in nfqueue.
3) Reject template conntrack in xt_cluster, otherwise access to
uninitialize conntrack fields are possible leading to WARN_ON
due to unset layer 3 protocol. From Wyatt Feng.
4) Make sure the IPv6 tunnel header is in the linear skb data
area before pulling. While at it remove incomplete NEXTHDR_DEST
support. From Lorenzo Bianconi. This possibly leading to crash
if IPv4 header is not in the linear area.
5) Use test_bit_acquire in ipset hash set to avoid reordering
of subsequent memory access. This is addressing a LLM related
report, no crash has been observed. From Jozsef Kadlecsik.
6) Use test_bit_acquire in ipset bitmap set too, for the same
reason as in the previous patch, from Jozsef Kadlecsik.
7) Call kfree_rcu() after rcu_assign_pointer() to address a
possible UaF if kfree_rcu() runs inmediately, which to my
understanding never happens. Never observed in practise,
reported by LLM. Also from Jozsef Kadlecsik.
8) Use disable_delayed_work_sync() instead cancel_delayed_work_sync()
to avoid that ipset GC handler re-queues work as reported by LLM.
From Jozsef Kadlecsik. This is for correctness.
9) Restore the check in nft_payload for exceeding payloda offset
over 2^16. From Florian Westphal. This fixes a silent truncation,
not a big deal, but better be assertive and reject it.
10) Validate NFT_META_BRI_IIFHWADDR can only run from bridge
prerouting. From Florian Westphal. Harmless but it could allow
to read bytes from skb->cb.
11) Zero out destination hardware address during the flowtable
path setup, also from Florian. This is a correctness fix, LLM
points that possible infoleak can happen but topology to achieve
it is not clear.
12) Skip IPv4 options if present when building the IPV4 reject reply.
Otherwise bytes in the IPv4 options header can be sent back to
origin where the ICMP header is being expected. Again from
Florian Westphal.
13) Replace timer API for expectation by GC worker approach. This
is implicitly fixing a race between nf_ct_remove_expectations()
which might fail to remove the expectation due to timer_del()
returning false because timer has expired and callback is
being run concurrently. This fix is addressing a crash that has
been already reported with a reproducer.
14) Check if br_vlan_get_pvid_rcu() fails, otherwise possible stack
infoleak of 4-bytes. From Florian Westphal.
* tag 'nf-26-06-21' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: nft_meta_bridge: fix NFT_META_BRI_IIFPVID stack leak
netfilter: nf_conntrack_expect: use conntrack GC to reap expectations
netfilter: nf_reject: skip iphdr options when looking for icmp header
netfilter: nft_flow_offload: zero device address for non-ether case
netfilter: nft_meta_bridge: add validate callback for get operations
netfilter: nft_payload: reject offsets exceeding 65535 bytes
netfilter: ipset: make sure gc is properly stopped
netfilter: ipset: fix order of kfree_rcu() and rcu_assign_pointer()
netfilter: ipset: Don't use test_bit() in lockless RCU readers in bitmap types
netfilter: ipset: Don't use test_bit() in lockless RCU readers in hash types
netfilter: flowtable: fix and simplify IP6IP6 tunnel handling
netfilter: xt_cluster: reject template conntracks in hash match
netfilter: nf_queue: pin bridge device while NFQUEUE holds fake dst
netfilter: flowtable: fix offloaded ct timeout never being extended
====================
Link: https://patch.msgid.link/20260620222738.112506-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In __ip_append_data(), when the paged-allocation branch is taken,
alloclen and pagedlen are computed as
alloclen = fragheaderlen + transhdrlen;
pagedlen = datalen - transhdrlen;
datalen already includes fraggap, but the fraggap bytes carried over
from the previous skb are copied into the new skb's linear area at
offset transhdrlen by the subsequent skb_copy_and_csum_bits(). The
linear area is therefore undersized by fraggap bytes while pagedlen is
overstated by the same amount.
The non-paged branch sets alloclen to fraglen, which already accounts
for fraggap because datalen does. Bring the paged branch in line by
adding fraggap to alloclen and subtracting it from pagedlen.
After this adjustment, copy no longer collapses to -fraggap on the
paged path, so remove the stale comment describing that old arithmetic.
Fixes: 8eb77cc739 ("ipv4: avoid partial copy for zc")
Signed-off-by: Jungwoo Lee <jwlee2217@gmail.com>
Signed-off-by: Wongi Lee <qw3rtyp0@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/ajFR1eLAIs42TN3g@DESKTOP-19IMU7U.localdomain
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Not a big deal but this hould have used the real ip header length and not the
base header size. As-is, if there are options then
nf_skb_is_icmp_unreach() result will be random.
Fixes: db99b2f2b3 ("netfilter: nf_reject: don't reply to icmp error messages")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Reject invalid `net.ipv4.tcp_reordering` values before they reach TCP
socket state. The sysctl is stored as an `int` but copied into the
`u32` `tp->reordering` field for new sockets, so negative writes wrap
to large values.
With `tcp_mtu_probing=2`, the wrapped value can overflow the
`tcp_mtu_probe()` size calculation and drive the MTU probing path into
an out-of-bounds read. Route `tcp_reordering` writes through
`proc_dointvec_minmax()` and require it to be at least 1. Also require
`tcp_max_reordering` to be at least 1 so the configured maximum cannot
become negative either.
When registering the table for a non-init network namespace, relocate
`extra2` pointers that refer into `init_net.ipv4` so the
`tcp_reordering` upper bound follows that namespace's
`tcp_max_reordering`.
Harden `tcp_mtu_probe()` itself by computing `size_needed` as `u64`.
This keeps the send queue and window checks from being bypassed through
signed integer overflow.
Fixes: 91cc17c0e5 ("[TCP]: MTUprobe: receiver window & data available checks fixed")
Cc: stable@vger.kernel.org
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Zhengchuan Liang <zcliangcn@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Wyatt Feng <bronzed_45_vested@icloud.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/1a5b7e1ef4d70fbad8c8ee0b82d8405f3c964a3d.1781395200.git.bronzed_45_vested@icloud.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
vti_changelink() operates on at most two netns, dev_net(dev) and the
tunnel link netns t->net. They differ once the device is created in or
moved to a netns other than the one the request runs in. The rtnl
changelink path checks CAP_NET_ADMIN only against dev_net(dev), so a
caller privileged there but not in t->net can rewrite a tunnel that
lives in t->net.
Gate vti_changelink() on rtnl_dev_link_net_capable() at its top,
before any attribute is parsed.
Reported-by: Xiao Liang <shaw.leon@gmail.com>
Closes: https://lore.kernel.org/netdev/CABAhCOSzP1vaThGV35_VnsRCb=87_CPjPVsTHbq905k8A+BuUg@mail.gmail.com/
Fixes: 895de9a348 ("vti4: Enable namespace changing")
Cc: stable@vger.kernel.org
Signed-off-by: Maoyi Xie <maoyixie.tju@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260612085941.3158249-4-maoyixie.tju@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ipip_changelink() operates on at most two netns, dev_net(dev) and the
tunnel link netns t->net. They differ once the device is created in or
moved to a netns other than the one the request runs in. The rtnl
changelink path checks CAP_NET_ADMIN only against dev_net(dev), so a
caller privileged there but not in t->net can rewrite a tunnel that
lives in t->net.
Gate ipip_changelink() on rtnl_dev_link_net_capable() at its top,
before any attribute is parsed.
Reported-by: Xiao Liang <shaw.leon@gmail.com>
Closes: https://lore.kernel.org/netdev/CABAhCOSzP1vaThGV35_VnsRCb=87_CPjPVsTHbq905k8A+BuUg@mail.gmail.com/
Fixes: 6c742e714d ("ipip: add x-netns support")
Cc: stable@vger.kernel.org
Signed-off-by: Maoyi Xie <maoyixie.tju@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260612085941.3158249-3-maoyixie.tju@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
A tunnel changelink() operates on at most two netns, dev_net(dev) and
the tunnel link netns t->net. They differ once the device is created in
or moved to a netns other than the one the request runs in. The rtnl
changelink path checks CAP_NET_ADMIN only against dev_net(dev), so a
caller privileged there but not in t->net can rewrite a tunnel that
lives in t->net.
Add rtnl_dev_link_net_capable() next to rtnl_get_net_ns_capable() in
net/core/rtnetlink.c. It requires CAP_NET_ADMIN in the link netns and is
skipped when the link netns is dev_net(dev), where the rtnl path already
checked it. The other patches in this series use the same helper.
Gate ipgre_changelink() and erspan_changelink() with it, at the top of
the op before any attribute is parsed, because the parsers update live
tunnel fields first. ipgre_netlink_parms() sets t->collect_md before
ip_tunnel_changelink() runs.
Commit 8b484efd5c ("ip6: vti: Use ip6_tnl.net in
vti6_siocdevprivate().") added the same check on the ioctl path. This
adds it on RTM_NEWLINK.
Reported-by: Xiao Liang <shaw.leon@gmail.com>
Closes: https://lore.kernel.org/netdev/CABAhCOSzP1vaThGV35_VnsRCb=87_CPjPVsTHbq905k8A+BuUg@mail.gmail.com/
Fixes: b57708add3 ("gre: add x-netns support")
Cc: stable@vger.kernel.org
Signed-off-by: Maoyi Xie <maoyixie.tju@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260612085941.3158249-2-maoyixie.tju@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'bpf-next-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
"Major changes:
- Recover from BPF arena page faults using a scratch page and add
ptep_try_set() for lockless empty-slot installs on x86 and arm64.
This allows BPF kfuncs to access arena pointers directly.
The 'arena_direct_access' stable branch was created for this work
and was pulled into sched-ext and bpf-next trees (Tejun Heo, Kumar
Kartikeya Dwivedi)
- Lift old restriction and support 6+ arguments in BPF programs and
kfuncs on x86 and arm64 (Yonghong Song, Puranjay Mohan)
Other features and fixes:
- Add 24-bit BTF vlen and reclaim unused bits in the BTF UAPI to ease
addition of new BTF kinds (Alan Maguire)
- Raise the maximum BPF call chain depth from 8 to 16 frames (Alexei
Starovoitov)
- Refactor object relationship tracking in the verifier and fix a
dynptr use-after-free bug (Amery Hung)
- Harden the signed program loader and reject exclusive maps as inner
maps (Daniel Borkmann)
- Replace the verifier min/max bounds fields with a circular number
(cnum) representation and improve 32->64 bit range refinements
(Eduard Zingerman)
- Introduce the arena library and runtime (libarena) with a buddy
allocator, rbtree and SPMC queue data structures, ASAN support and
a parallel test harness. Allow subprograms to return arena pointers
and switch to a BTF type-tag based __arena annotation (Emil
Tsalapatis)
- Cache build IDs in the sleepable stackmap path and avoid faultable
build ID reads under mm locks (Ihor Solodrai)
- Introduce the tracing_multi link to attach a single BPF program to
many kernel functions at once. Allow specifying the uprobe_multi
target via FD (Jiri Olsa)
- Extend the bpf_list family of kfuncs with bpf_list_add/del(), and
bpf_list_is_first/is_last/empty() (Kaitao Cheng)
- Extend the BPF syscall with common attributes support for
prog_load, btf_load and map_create (Leon Hwang)
- Wrap rhashtable as BPF map (Mykyta Yatsenko, Herbert Xu)
- Add sleepable support for tracepoint programs and fix deadlocks in
LRU map due to NMI reentry (Mykyta Yatsenko)
- Fix OOB access in bpf_flow_keys, fix nullness analysis of inner
arrays, enforce write checks for global subprograms (Nuoqi Gui)
- Report the maximum combined stack depth and print a breakdown of
instructions processed per subprogram (Paul Chaignon)
- Add an XDP load-balancer benchmark and arm64 JIT support for stack
arguments (Puranjay Mohan)
- Add kfuncs to traverse over wakeup_sources (Samuel Wu)
- Allow sleepable BPF programs to use LPM trie maps directly (Vlad
Poenaru)
- Many more fixes and cleanups across the verifier, BTF, sockmap,
devmap, bpffs, security hooks, s390/riscv/loongarch JITs,
rqspinlock, libbpf, bpftool, selftests"
* tag 'bpf-next-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (336 commits)
selftests/bpf: Work around llvm stack overflow in crypto progs
selftests/bpf: add test for bpf_msg_pop_data() overflow
bpf, sockmap: fix integer overflow in bpf_msg_pop_data() bounds check
sockmap: Fix use-after-free in udp_bpf_recvmsg()
bpf, sockmap: keep sk_msg copy state in sync
bpf, sockmap: Fix wrong rsge offset in bpf_msg_push_data()
bpf, sockmap: reject overflowing copy + len in bpf_msg_push_data()
selftsets/bpf: Retry map update on helper_fill_hashmap()
selftests/bpf: Add test for sleepable lsm_cgroup rejection
selftests/bpf: Add test to verify the fix for bpf_setsockopt() helper
bpf: Fix bpf_get/setsockopt to tos for ipv4-mapped ipv6 socket
selftests/bpf: Avoid static LLVM linking for cross builds
selftests/bpf: Use common CFLAGS for urandom_read
selftests/bpf: Initialize operation name before use
tools/bpf: build: Append extra cflags
libbpf: Initialize CFLAGS before including Makefile.include
bpftool: Append extra host flags
bpftool: Avoid adding EXTRA_CFLAGS to HOST_CFLAGS
bpftool: Pass host flags to bootstrap libbpf
selftests/bpf: correct CONFIG_PPC64 macro name in comment
...
syzbot reported use-after-free of net->ipv4.rules_ops. [0]
It can be reproduced with these commands:
while true; do
ip netns add ns1
ip -n ns1 link set dev lo up
ip -n ns1 address add 192.0.2.1/24 dev lo
ip -n ns1 link add name dummy1 up type dummy
ip -n ns1 address add 198.51.100.1/24 dev dummy1
ip -n ns1 rule add ipproto tcp sport 12345 table 12345
ip -n ns1 fou add port 5555 ipproto 47 local 192.0.2.1 peer 198.51.100.2 peer_port 54321
ip netns del ns1
done
The cited commit moved fib4_rules_exit() earlier to ->exit_rtnl(),
but the kernel socket destroyed in ->exit() could eventually reach
__fib_lookup().
I left fib4_rules_exit() in ->exit_rtnl() because fib4_rule_delete()
calls fib_unmerge(), which requires RTNL.
However, when ->delete() is called, ->configure() has already been
called, thus fib_unmerge() in ->delete() has no effect.
Let's remove fib_unmerge() in fib4_rule_delete() and move
fib4_rules_exit() to ->exit().
Many thanks to Ido Schimmel for providing the nice repro very quickly.
Note that we can make fib_rules_ops.delete() return void once
net-next opens.
[0]:
BUG: KASAN: slab-use-after-free in fib_rules_lookup+0x15e/0xeb0 net/core/fib_rules.c:321
Read of size 8 at addr ffff88804ec4c680 by task kworker/u8:21/12641
CPU: 0 UID: 0 PID: 12641 Comm: kworker/u8:21 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: netns cleanup_net
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description+0x55/0x1e0 mm/kasan/report.c:378
print_report+0x58/0x70 mm/kasan/report.c:482
kasan_report+0x117/0x150 mm/kasan/report.c:595
fib_rules_lookup+0x15e/0xeb0 net/core/fib_rules.c:321
__fib_lookup+0x106/0x210 net/ipv4/fib_rules.c:96
ip_route_output_key_hash_rcu+0x294/0x2720 net/ipv4/route.c:2811
ip_route_output_key_hash+0x18d/0x2a0 net/ipv4/route.c:2702
__ip_route_output_key include/net/route.h:169 [inline]
ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2929
ip4_datagram_release_cb+0x89d/0xbe0 net/ipv4/datagram.c:118
release_sock+0x206/0x260 net/core/sock.c:3861
inet_shutdown+0x2b1/0x390 net/ipv4/af_inet.c:950
udp_tunnel_sock_release+0x6d/0x80 net/ipv4/udp_tunnel_core.c:197
fou_release net/ipv4/fou_core.c:562 [inline]
fou_exit_net+0x17d/0x1f0 net/ipv4/fou_core.c:1230
ops_exit_list net/core/net_namespace.c:199 [inline]
ops_undo_list+0x43d/0x8d0 net/core/net_namespace.c:252
cleanup_net+0x572/0x810 net/core/net_namespace.c:702
process_one_work kernel/workqueue.c:3314 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478
kthread+0x389/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Fixes: 759923cf03 ("ipv4: fib: Convert fib_net_exit_batch() to ->exit_rtnl().")
Reported-by: syzbot+965506b59a2de0b6905c@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/6a315824.b0403584.28d0ff.0000.GAE@google.com/
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260616191359.4142661-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Merge in late fixes in preparation for the net-next PR.
Conflicts:
net/tls/tls_sw.c
406e8a651a ("net: skmsg: preserve sg.copy across SG transforms")
79511603a6 ("tls: remove dead sockmap (psock) handling from the SW path")
drivers/net/ethernet/microsoft/mana/mana_en.c
f8fd56977e ("net: mana: guard TX wq object destroy with INVALID_MANA_HANDLE check")
d07efe5a6e ("net: mana: Use per-queue allocation for tx_qp to reduce allocation size")
https://lore.kernel.org/ajAPXu-C_PuTgV-a@sirena.org.uk
No adjacent changes.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Currently sk_rethink_txhash() re-rolls the socket's txhash on RTO, PLB,
and spurious-retransmission events, but the cached route is reused and
the new hash is not propagated into the ECMP path selection logic. Two
changes are needed to make rehash select a different local ECMP path:
1. Add __sk_dst_reset() alongside sk_rethink_txhash() in
tcp_write_timeout(), tcp_rcv_spurious_retrans(), and
tcp_plb_check_rehash() so the cached dst is invalidated and the
next transmit triggers a fresh route lookup.
2. Set fl6->mp_hash from sk_txhash (or tcp_rsk(req)->txhash for
SYN/ACK retransmits and syncookies) in tcp_v6_connect(),
inet6_sk_rebuild_header(), inet6_csk_route_req(),
inet6_csk_route_socket(), tcp_v6_send_response(), and
cookie_v6_check() so fib6_select_path() picks a path based on the
new hash.
The mp_hash override only applies to fib_multipath_hash_policy 0 (the
default L3 policy). Its hash includes the flow label, but that is 0 by
default -- np->flow_label is unset, and auto_flowlabels only computes
the on-wire label later, per packet -- so flows to the same peer share
one local path. Keying the hash on sk_txhash makes the local path
per-connection and lets a rehash re-select it. Policies 1-3 are left
unchanged.
The mp_hash assignment is factored into a small helper,
ip6_ecmp_set_mp_hash(), shared by inet6_csk_route_req(),
inet6_csk_route_socket(), tcp_v6_connect(), inet6_sk_rebuild_header(),
tcp_v6_send_response(), and cookie_v6_check(). It applies
(txhash >> 1) ?: 1 for policy 0 (the >> 1 keeps mp_hash in the 31-bit
range; ?: 1 keeps it non-zero, since 0 would fall back to
rt6_multipath_hash()). inet6_csk_route_socket() calls it only for
sk_protocol == IPPROTO_TCP so that non-TCP callers (e.g., L2TP via
inet6_csk_xmit) fall through to rt6_multipath_hash() and retain their
existing flow-key-based ECMP behavior.
tcp_v6_send_response() also sets mp_hash from the response txhash so
that a control packet (a RST from the full socket, or an ACK from a
time-wait socket) selects the same local ECMP nexthop as the
connection's txhash rather than falling back to the flow hash. The
time-wait socket's tw_txhash is copied from sk_txhash when the
connection enters TIME_WAIT, so it reflects any rehash that occurred.
Setting mp_hash explicitly is necessary because the default ECMP hash
derives from fl6->flowlabel via np->flow_label, which is not updated
from sk_txhash (REPFLOW is off by default). ip6_make_flowlabel()
cannot help either, as it runs after the route lookup.
As a consequence, for policy 0 the local ECMP path of an IPv6 TCP
flow follows sk_txhash even when fl6->flowlabel is non-zero, e.g. a
reflected (REPFLOW) or explicitly set (IPV6_FLOWLABEL_MGR) flow
label. This is intentional: only local path selection changes, so
rehash can recover from a failed path; the on-wire flow label is
unchanged.
sk_set_txhash() is moved before ip6_dst_lookup_flow() in
tcp_v6_connect() so the initial ECMP path is selected by the same
txhash that subsequent route rebuilds will use. This avoids
unintended path changes when the cached dst is naturally invalidated
(e.g., by PMTU discovery or route changes).
The rehash sites (tcp_write_timeout(), tcp_plb_check_rehash(), and
tcp_rcv_spurious_retrans()) call __sk_rethink_txhash_reset_dst(),
which re-rolls the txhash and, when it changed, drops the cached dst
so the next transmit re-runs route selection. The dst reset is
guarded by sk->sk_family == AF_INET6 since IPv4 ECMP does not
currently use sk_txhash for path selection. For IPv4-mapped IPv6
sockets this produces a redundant dst reset on a cold path
(RTO/PLB); the subsequent IPv4 route lookup returns the same result.
The helper is deliberately separate from sk_rethink_txhash() itself:
dst_negative_advice() calls sk_rethink_txhash() before its own dst op,
so resetting the dst inside sk_rethink_txhash() would skip that op
(e.g. rt6_remove_exception_rt()).
For syncookies, cookie_init_sequence() computes the cookie value
before route_req() and sets txhash so the SYN-ACK selects the same
ECMP path that cookie_v6_check() will use when the full socket is
created. cookie_tcp_reqsk_init() derives txhash from the cookie so
the full socket's ECMP path matches the SYN-ACK. Both the SYN-ACK
assignment in tcp_conn_request() and the full-socket assignment in
cookie_tcp_reqsk_init() set txhash from the cookie for IPv4 and IPv6
alike. On IPv6 this drives ECMP path selection; on IPv4, which does
not use sk_txhash for ECMP, it only affects TX-queue selection. That
selection scales the hash by its high bits (reciprocal_scale()), which
are uniform in the keyed secure_tcp_syn_cookie() output -- the MSS index
only perturbs the low bits -- so the queue distribution matches
net_tx_rndhash().
cookie_init_sequence() is split from the former version that also
called tcp_synq_overflow() and incremented SYNCOOKIESSENT; those
side effects are now in cookie_record_sent(), called after
route_req() succeeds so they are not bumped when route_req() fails.
cookie_record_sent() is guarded by CONFIG_SYN_COOKIES to
match the guard on tcp_synq_overflow(). route_req() receives 0 as
tw_isn for the syncookie path so that tcp_v6_init_req() still saves
ireq->pktopts for REPFLOW flowlabel reflection and IPv6 cmsg
options. The ecn_ok clear for syncookies without timestamps stays
after tcp_ecn_create_request() so it takes precedence.
Signed-off-by: Neil Spring <ntspring@meta.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260615042158.1600746-2-ntspring@meta.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'nf-next-26-06-14' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next
Pablo Neira Ayuso says:
====================
Netfilter/IPVS updates for net-next
The following patchset contains Netfilter/IPVS updates for net-next.
More specifically, this contains conncount rework to address AI related
reports, assorted Netfiter updates and two small incremental updates on
IPVS:
1) Replace old obsolete workqueues (system_wq, system_unbound_wq)
in IPVS, from Marco Crivellari.
2) Replace WARN_ON{_ONCE} by DEBUG_NET_WARN_ON_ONCE in nf_tables.
In the recent years, reporters say that the use of WARN_ON{_ONCE}
in conjunction with panic_on_warn=1 results in DoS. Let's replace
it by DEBUG_NET_WARN_ON_ONCE so this is only exercised by test
infrastructure and fuzzers, while also providing context to AI
agents. From Fernando F. Mancera.
Five patches from Florian Westphal to address AI reports in the conncount
infrastructures:
3) Fix missing rcu read lock section when calling
__ovs_ct_limit_get_zone_limit().
4) Add a dedicate lock per rbtree tree, this increases memory
usage but it should improve scalability.
5) Add a helper function to find the rbtree node, no functional
changes are intented.
6) Add sequence counter to detect concurrent tree modifications
and retry lookups.
7) Add locks to GC conncount walk and address other nitpicks.
Then, several assorted updates:
8) Defensive Tree-wide addition of NULL checks for ct extensions.
9) Bail out if flowtable bypass cannot be fully set up from the
flow offload expression, instead of lazy building a likely
incomplete one.
10) Fix documentation for the new conn_max sysctl toggle in IPVS.
11) Add nf_dev_xmit_recursion*() helpers and use them, to address
recent AI reports.
* tag 'nf-next-26-06-14' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
netfilter: nf_dup_netdev: add nf_dev_xmit_recursion*() helpers and use them
ipvs: fix doc syntax for conn_max sysctl
netfilter: flowtable: bail out if forward path cannot be discovered
netfilter: conntrack: check NULL when retrieving ct extension
netfilter: nf_conncount: gc and rcu fixes
netfilter: nf_conncount: add sequence counter to detect tree modifications
netfilter: nf_conncount: split count_tree_node rbtree walk into helper
netfilter: nf_conncount: use per nf_conncount_data spinlocks
netfilter: nf_conncount: callers must hold rcu read lock
netfilter: nf_tables: use DEBUG_NET_WARN_ON_ONCE in packet and control paths
ipvs: Replace use of system_unbound_wq with system_dfl_long_wq
====================
Link: https://patch.msgid.link/20260614114605.474783-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Currently, IPv4 routes are flushed in ->exit_batch() after
all devices are unregistered.
Unlike IPv6, IPv4 routes are not added from the fast path,
so we can flush routes before default_device_exit_batch().
Let's call ip_fib_net_exit() from ->exit_rtnl() to save
one RTNL locking dance.
ip_fib_net_exit() must use list_del_rcu() for fib_table
for the fast path on dying dev.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260612063225.455191-6-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We will call ip_fib_net_exit() from ->exit_rtnl().
All fib_table will be destroyed before devices are unregistered.
During device unregistration, inetdev_destroy() could call
fib_del_ifaddr(), which calls fib_magic(RTM_DELROUTE).
fib_magic() calls fib_new_table(), but we do not want to create
a new table after ip_fib_net_exit() destroys all tables.
As a prep, let's add check_net() before fib_trie_table() in
fib_new_table().
fib_trie_table() is also called from fib_trie_unmerge(), but
fib_get_table() fails first in fib_unmerge(), so the same
problem does not occur there.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260612063225.455191-5-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We will call ip_fib_net_exit() from ->exit_rtnl().
However, some paths will still access net->ipv4.fib_table_hash
after ->exit_rtnl().
For example, fib_flush() is called from fib_disable_ip() for
NETDEV_UNREGISTER.
Let's move kfree(net->ipv4.fib_table_hash) and fib4_notifier_exit()
from ip_fib_net_exit() to its caller.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260612063225.455191-4-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We will call ip_fib_net_exit() from ->exit_rtnl().
Since the exit callbacks are called in the following order,
1. ->pre_exit()
~~~ synchronize_rcu() ~~~
2. ->exit_rtnl() : ip_fib_net_exit()
3. ->exit() : fib_proc_exit() / nl_fib_lookup_exit()
4. ->exit_batch() : fib4_semantics_exit()
the reverse order of fib_net_init() would get messed up.
Let's move fib_proc_exit() and nl_fib_lookup_exit() to ->pre_exit().
This is fine because procfs/netlink access from userspace cannot
occur at this point and synchronize_rcu() is not needed.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260612063225.455191-3-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Even when fib_table_flush() is called with flush_all true, it does
not flush all fib_info due to this condition:
!(fi->fib_flags & RTNH_F_DEAD) && !fib_props[fa->fa_type].error)
This creates an implicit ordering between default_device_exit_batch()
and fib_net_exit_batch().
fib_table_flush(flush_all=true) must be called after all devices
are NETDEV_UNREGISTERed, which is after nexthop_flush_dev() marks
RTNH_F_DEAD.
This would cause memory leak if the order were reversed.
fib_table_flush() does not skip non-dead error routes when flush_all
is true:
!flush_all &&
!(fi->fib_flags & RTNH_F_DEAD) && fib_props[fa->fa_type].error
Let's merge the two conditions not to skip all non-dead fib_info
during netns dismantle.
Note that we could further apply !flush_all to the basic table
id check and the rtmsg_fib() call in the loop.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260612063225.455191-2-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
nf_ct_ext_find() might return NULL if ct extension is not found.
Add also the null checks to:
- nfct_help()
- nfct_help_data()
- nfct_seqadj()
- nfct_nat()
This is defensive, for safety reasons.
nf_ct_ext_find() used to return NULL if the extension is stale for
unconfirmed conntracks if the genid validation fails.
Skip NULL check in nf_nat_inet_fn() given this is valid to be NULL
for non-initialized ct nat extensions.
While at it, fetch ct helper area in nf_ct_expect_related_report() only
once and pass it on to other ancilliary functions. Replace WARN_ON()
by WARN_ON_ONCE() in nf_ct_unlink_expect_report().
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When IPv4 device configuration parameters are updated via netlink, the
kernel currently only updates the value. This bypasses several
post-modification actions that occur when these same parameters are
updated via sysctl, such as flushing the routing cache or emitting
RTM_NEWNETCONF notifications.
This patch addresses the inconsistency by calling the
devinet_conf_post_set() helper inside inet_set_link_af(). If a flush is
required, we defer it until the netlink attribute parsing loop
completes.
This ensures consistent behavior and side-effects for devconf changes,
regardless of whether they are initiated via sysctl or netlink.
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Link: https://patch.msgid.link/20260609204520.4670-2-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The logic for handling IPv4 devconf sysctls is scattered. Notification
and cache flushes are managed in devinet_conf_proc(), while a separate
ipv4_doint_and_flush() function and DEVINET_SYSCTL_FLUSHING_ENTRY macro
is used for properties that solely require a cache flush.
This patch refactors the sysctl handling by introducing a centralized
helper, devinet_conf_post_set(). This new function evaluates the changed
attribute and handles all necessary operations like triggering netlink
notifications. It returns a boolean indicating whether a routing cache
flush is required.
Note that the boolean is necessary as this function will be re-used for
netlink IPv4 devconf handling where the cache flushing must wait until
all the attributes have been processed.
Finally, this is introducing a small change in behavior for
IPV4_DEVCONF_ROUTE_LOCALNET. As commit d0daebc3d6 ("ipv4: Add
interface option to enable routing of 127.0.0.0/8") intended, the cache
flush should only be performed when ROUTE_LOCALNET changes from 1 to 0.
Unfortunately, this was not true because while implementing it the
DEVINET_SYSCTL_FLUSHING_ENTRY was used for the attribute, making the
code related to it on devinet_conf_proc() dead.
IPV4_DEVCONF_FORWARDING is still being handled separately as it requires
more operations.
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Link: https://patch.msgid.link/20260609204520.4670-1-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit 0e24d17bd9 ("tcp: implement RFC 7323 window retraction
receiver requirements") removed the special FIN case that
was added in commit 1e3bb184e9 ("tcp: re-enable acceptance of
FIN packets when RWIN is 0").
If a peer sends a segment containing data and a FIN flag before
it learns about our window retraction and has a buggy TCP stack,
it might place the FIN one byte beyond what it thinks is the
right edge of the window (i.e., max_window_edge + 1).
The data portion (end_seq - th->fin) will end exactly at max_window_edge.
In this case, we will drop the packet if our receive queue is not empty,
even though the data was sent within the window we previously allowed.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Simon Baatz <gmbnomis@gmail.com>
Link: https://patch.msgid.link/20260608151452.706822-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'ipsec-next-2026-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next
Steffen Klassert says:
====================
pull request (net-next): ipsec-next 2026-06-12
1) Replace the open-coded manual cleanup in xfrm_add_policy() error
path with xfrm_policy_destroy() for consistency with
xfrm_policy_construct().
From Deepanshu Kartikey.
2) Limit XFRMA_TFCPAD to a sensible maximum (max IP length, 64k) since
u32 is excessive for traffic flow confidentiality padding.
From David Ahern.
3) Add a new netlink message XFRM_MSG_MIGRATE_STATE that
allows migrating individual IPsec SAs independently of
their policies. The existing XFRM_MSG_MIGRATE is tightly coupled
to policy+SA migration, lacks SPI for unique SA identification,
and cannot express reqid changes or migrate Transport mode
selectors. The new interface identifies the SA via SPI and mark,
supports reqid changes, address family changes, encap removal,
and uses an atomic create+install flow under x->lock to prevent
SN/IV reuse during AEAD SA migration.
From Antony Antony.
* tag 'ipsec-next-2026-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next:
xfrm: add documentation for XFRM_MSG_MIGRATE_STATE
xfrm: restrict netlink attributes for XFRM_MSG_MIGRATE_STATE
xfrm: add XFRM_MSG_MIGRATE_STATE for single SA migration
xfrm: make xfrm_dev_state_add xuo parameter const
xfrm: extract address family and selector validation helpers
xfrm: refactor XFRMA_MTIMER_THRESH validation into a helper
xfrm: move encap and xuo into struct xfrm_migrate
xfrm: add error messages to state migration
xfrm: add state synchronization after migration
xfrm: check family before comparing addresses in migrate
xfrm: split xfrm_state_migrate into create and install functions
xfrm: rename reqid in xfrm_migrate
xfrm: fix NAT-related field inheritance in SA migration
xfrm: allow migration from UDP encapsulated to non-encapsulated ESP
xfrm: add extack to xfrm_init_state
xfrm: remove redundant assignments
xfrm: Reject excessive values for XFRMA_TFCPAD
xfrm: cleanup error path in xfrm_add_policy()
====================
Link: https://patch.msgid.link/20260612074725.1760473-1-steffen.klassert@secunet.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ip_tunnel_xmit() runs locklessly (dev->lltx == true).
ipgre_err() and ipip_err() also run locklessly.
We need to add READ_ONCE() and WRITE_ONCE() annotations
around t->err_count and t->err_time.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260611165247.2710257-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
A child socket inherits the listener's bpf_sock_ops_cb_flags via
sk_clone_lock(). If its setup fails in tcp_v4_syn_recv_sock() /
tcp_v6_syn_recv_sock(), the child is freed through put_and_exit, where
inet_csk_prepare_forced_close() drops the socket lock and tcp_done() runs
without it.
If BPF_SOCK_OPS_STATE_CB_FLAG was inherited, tcp_done() -> tcp_set_state()
calls tcp_call_bpf(), which expects the lock and trips sock_owned_by_me():
WARNING: include/net/sock.h:1799 at tcp_set_state+0x433/0x550
RIP: 0010:tcp_set_state+0x433/0x550 include/net/sock.h:1799
Call Trace:
<IRQ>
tcp_done+0xba/0x250 net/ipv4/tcp.c:5095
tcp_v4_syn_recv_sock+0x850/0xa50 net/ipv4/tcp_ipv4.c:1787
tcp_check_req+0xf30/0x1360 net/ipv4/tcp_minisocks.c:926
tcp_v4_rcv+0x1047/0x1b50 net/ipv4/tcp_ipv4.c:2164
</IRQ>
The child is freed before it is ever established, so it should run no
sock_ops callback. Clear its cb flags in inet_csk_prepare_for_destroy_sock(),
the common point for the IPv4, IPv6 and chtls forced-close paths and for the
MPTCP ->syn_recv_sock() failure path (dispose_child), which reaches tcp_done()
on a child that was never established too.
Suggested-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Fixes: d44874910a ("bpf: Add BPF_SOCK_OPS_STATE_CB")
Signed-off-by: Sechang Lim <rhkrqnwk98@gmail.com>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260611092923.1895982-1-rhkrqnwk98@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
