The userspace PM increments extra_subflows after __mptcp_subflow_connect()
succeeds, but __mptcp_subflow_connect() calls mptcp_pm_close_subflow()
on failure to roll back the pre-increment done by the kernel PM's fill_*()
helpers. Because the userspace PM hasn't incremented yet at that point,
this decrement is spurious and causes extra_subflows to underflow.
Fix it by aligning the userspace PM with the kernel PM: increment
extra_subflows before calling __mptcp_subflow_connect(), so the existing
error path in subflow.c correctly rolls it back on failure. Also simplify
the error handling by taking pm.lock only when needed for cleanup.
Fixes: 77e4b94a3d ("mptcp: update userspace pm infos")
Cc: stable@vger.kernel.org
Signed-off-by: Tao Cui <cuitao@kylinos.cn>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260602-net-mptcp-misc-fixes-7-1-rc7-v2-5-856831229976@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In MPTCP connection, the `window` field in the TCP header refers to the
MPTCP-level rcv_nxt and it's right edge should not move backward. Such
constraint is enforced at DSS option generation time.
At the same time, the TCP stack ensures independently that the TCP-level
rcv wnd right's edge does not move backward. That in turn causes artificial
inflating of the MPTCP rcv window when the incoming data is acked at the
TCP level and is OoO in the MPTCP sequence space (or lands in the backlog).
As a consequence, the incoming traffic can exceed the receiver rcvbuf size
even when the sender is not misbehaving.
Prevent such scenario forcibly allowing the TCP subflow to shrink the
TCP-level rcv wnd regardless of the current netns setting.
Fixes: f3589be0c4 ("mptcp: never shrink offered window")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260602-net-mptcp-misc-fixes-7-1-rc7-v2-4-856831229976@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The MPTCP output path access locklessly the MPTCP-level ack_seq
in multiple times, using possibly different values for the data_ack
in the DSS option and to compute the announced rcv wnd for the same
packet.
Refactor the cote to avoid inconsistencies which may confuse the
peer. Also ensure that the MPTCP level rcv wnd is updated only when
the egress packet actually contains a DSS ack.
Fixes: fa3fe2b150 ("mptcp: track window announced to peer")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260602-net-mptcp-misc-fixes-7-1-rc7-v2-3-856831229976@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Sashiko noted that retransmission with csum enabled can actually
transmit new data, but currently the relevant code does not update
accordingly snd_nxt.
The may cause incoming ack drop and an endless retransmission loop.
Address the issue incrementing snd_nxt as needed.
Fixes: 4e14867d5e ("mptcp: tune re-injections for csum enabled mode")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260602-net-mptcp-misc-fixes-7-1-rc7-v2-2-856831229976@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The mptcp_recvmsg() can fill MPTCP socket receive queue via
mptcp_move_skbs(), but currently does not try to wakeup any listener,
because the same process is going to check the receive queue soon.
When multiple threads are reading from the same fd, the above can
cause stall. Add the missing wakeup.
Fixes: 6771bfd9ee ("mptcp: update mptcp ack sequence from work queue")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260602-net-mptcp-misc-fixes-7-1-rc7-v2-1-856831229976@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch restricts setting Loose Source and Record Route (LSRR)
and Strict Source and Record Route (SSRR) IP options to users
with CAP_NET_RAW capability.
This prevents unprivileged applications from forcing packets to route
through attacker-controlled nodes to leak TCP ISN and possibly other
protocol information.
While LSRR and SSRR are commonly filtered in many network environments,
they may still be supported and forwarded along some network paths.
RFC 7126 (Recommendations on Filtering of IPv4 Packets Containing
IPv4 Options) recommend to drop these options in 4.3 and 4.4.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: Tamir Shahar <tamirthesis@gmail.com>
Reported-by: Amit Klein <aksecurity@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260602161547.2642155-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Currently inq_len is updated only when the whole skb is consumed.
If only part of the data is read, following SIOCINQ query would
get value greater than what actually left.
This change update inq_len timely in unix_stream_read_generic(),
and adjust unix_stream_read_skb() accordingly to prevent
repetitive update.
Fixes: f4e1fb04c1 ("af_unix: Use cached value for SOCK_STREAM in unix_inq_len().")
Signed-off-by: Jianyu Li <jianyu.li@mediatek.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260601113640.231897-2-jianyu.li@mediatek.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
aarp_alloc() allocates struct aarp_entry without zeroing it, but only
initializes refcnt and packet_queue. When an unresolved AARP entry is
created, hwaddr[ETH_ALEN] is left uninitialized.
aarp_seq_show() later prints this field with %pM when users read
/proc/net/atalk/arp. This can expose 6 bytes of stale heap data for
each unresolved entry.
Fix this by zero-initializing struct aarp_entry at allocation time.
Reported-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Reported-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn>
Reported-by: Ao Wang <wangao@seu.edu.cn>
Reported-by: Xuewei Feng <fengxw06@126.com>
Reported-by: Qi Li <qli01@tsinghua.edu.cn>
Reported-by: Ke Xu <xuke@tsinghua.edu.cn>
Signed-off-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260529105017.81531-1-zhaoyz24@mails.tsinghua.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The TX metadata area resides in the UMEM buffer which is memory-mapped
and concurrently writable by userspace. In xsk_skb_metadata(),
csum_start and csum_offset are read from shared memory for bounds
validation, then read again for skb assignment. A malicious userspace
application can race to overwrite these values between the two reads,
bypassing the bounds check and causing out-of-bounds memory access
during checksum computation in the transmit path.
Fix this by reading csum_start and csum_offset into local variables
once, then using the local copies for both validation and assignment.
Note that other metadata fields (flags, launch_time) and the cached
csum fields may be mutually inconsistent due to concurrent userspace
writes, but this is benign: the only security-critical invariant is
that each field's validated value is the same one used, which local
caching guarantees.
Closes: https://lore.kernel.org/all/20260503200927.73EA1C2BCB4@smtp.kernel.org/
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Fixes: 48eb03dd26 ("xsk: Add TX timestamp and TX checksum offload support")
Link: https://patch.msgid.link/20260530042630.80626-1-kerneljasonxing@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
syzbot reported a splat [1]: a slab-use-after-free in
ipv6_chk_acast_addr(), which walks the global inet6_acaddr_lst[] hash
under RCU and dereferences a struct ifacaddr6 that has already been
freed while still linked in the hash, so a later reader walks into a
dangling node.
In __ipv6_dev_ac_inc() the aca is allocated with refcount 1, then
aca_get() bumps it to 2 to keep it alive across the unlocked region.
It is published to idev->ac_list under idev->lock, but
ipv6_add_acaddr_hash() runs after write_unlock_bh(). A concurrent
teardown (ipv6_ac_destroy_dev() from addrconf_ifdown(), under RTNL)
can slip into that window:
CPU0 __ipv6_dev_ac_inc CPU1 ipv6_ac_destroy_dev (RTNL)
------------------------------ ------------------------------------
aca_alloc() refcnt 1
aca_get() refcnt 2
write_lock_bh(idev->lock)
add aca to ac_list
write_unlock_bh(idev->lock)
write_lock_bh(idev->lock)
pull aca off ac_list
write_unlock_bh(idev->lock)
ipv6_del_acaddr_hash(aca)
hlist_del_init_rcu() is a no-op,
aca is not in the hash yet
aca_put() refcnt 2->1
ipv6_add_acaddr_hash(aca)
aca now inserted into the hash
aca_put() refcnt 1->0
call_rcu(aca_free_rcu) -> kfree(aca)
The hash removal becomes a no-op because the insertion has not
happened yet, so once CPU0 inserts and drops the last reference, the
aca is freed while still linked in inet6_acaddr_lst[], and readers
dereference freed memory after the slab slot is reused.
This window opened once RTNL stopped serializing the join path against
device teardown. Move ipv6_add_acaddr_hash() inside the idev->lock
section so the ac_list and hash insertions are atomic with respect to
teardown: a racing remover now either misses the aca entirely or finds
it in both lists.
acaddr_hash_lock is now nested under idev->lock, which is acquired in
softirq context, so switch all acaddr_hash_lock sites to spin_lock_bh()
to avoid the irq lock inversion reported in [2].
[1] https://syzkaller.appspot.com/bug?extid=a01df04303c131efbf3a
[2] https://lore.kernel.org/netdev/6a194ef7.ba3b1513.1890b4.0000.GAE@google.com/
Reported-by: syzbot+819eb928d120d2bdad0e@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/6a191f87.ce022c6e.138e56.0003.GAE@google.com/T/
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Fixes: eb1ac9ff6c ("ipv6: anycast: Don't hold RTNL for IPV6_JOIN_ANYCAST.")
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260529152219.235475-1-jiayuan.chen@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The SCTP exact sock_diag lookup can hold a transport reference, block on
lock_sock(sk), and then resume after sctp_association_free() has marked
the association dead and freed its bind address list.
When that happens, inet_assoc_attr_size() and
inet_diag_msg_sctpasoc_fill() can still dereference association state
that is no longer valid for reporting. In particular,
inet_diag_msg_sctpasoc_fill() may read an empty bind-address list as a
real sctp_sockaddr_entry and trigger an out-of-bounds read from
unrelated association memory.
Reject the association after taking the socket lock if it has been
reaped or detached from the endpoint, and report the lookup as stale.
This keeps the exact dump-one path from formatting torn association
state.
Fixes: 8f840e47f1 ("sctp: add the sctp_diag.c file")
Cc: stable@kernel.org
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Reported-by: Zhengchuan Liang <zcliangcn@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Zhao Zhang <zzhan461@ucr.edu>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/fac6043fa20a2ff68e12958c431836f692c51268.1780113823.git.zzhan461@ucr.edu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The RDS IB connection teardown path is written so it can run during
partial startup and on repeated shutdown attempts. It uses NULL
pointers to distinguish resources that are still owned from resources
that have already been released.
When rds_ib_setup_qp() fails after allocating i_sends but before
allocating i_recvs, the sends_out path frees i_sends without clearing
the pointer. A later shutdown pass can still treat that stale pointer
as a live send ring allocation.
Clear i_sends after vfree() in the error unwind path so the existing
shutdown logic continues to use the correct ownership state.
Fixes: 3b12f73a5c ("rds: ib: add error handle")
Cc: stable@kernel.org
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Zhengchuan Liang <zcliangcn@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Yuqi Xu <xuyq21@lenovo.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Reviewed-by: Allison Henderson <achender@kernel.org>
Link: https://patch.msgid.link/5a0f7624bb9845a7b67d26166a150b59e7f394ce.1779632468.git.xuyq21@lenovo.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The receive-side GARP attribute parser computes dlen with reversed
operands:
dlen = sizeof(*ga) - ga->len;
ga->len is the on-wire attribute length and includes the GARP attribute
header. For normal attributes with data, ga->len is larger than
sizeof(*ga), so the subtraction underflows in unsigned arithmetic.
The resulting value is later passed to garp_attr_lookup(), whose length
argument is u8. After truncation, the parsed data length usually no
longer matches the length stored for locally registered attributes, so
received Join/Leave events are ignored. This breaks the GARP receive path
for common attributes, such as GVRP VLAN registration attributes.
Compute the data length as the attribute length minus the header length.
Fixes: eca9ebac65 ("net: Add GARP applicant-only participant")
Reported-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Reported-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn>
Reported-by: Ao Wang <wangao@seu.edu.cn>
Reported-by: Xuewei Feng <fengxw06@126.com>
Reported-by: Qi Li <qli01@tsinghua.edu.cn>
Reported-by: Ke Xu <xuke@tsinghua.edu.cn>
Signed-off-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260527083200.42861-1-zhaoyz24@mails.tsinghua.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'nf-26-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Pablo Neira Ayuso says:
====================
Netfilter/IPVS fixes for net
The following patchset contains Netfilter/IPVS fixes for net:
1) Fix splat with PREEMPT_RCU because smp_processor_id() in nfqueue,
from Fernando Fernandez Mancera.
2) Fix possible use of pointer to old IPVS scheduler after RCU grace
period when editing service, from Julian Anastasov.
3) Fix possible forever RCU walk over rt->fib6_siblings in nft_fib6,
if rt is unlinked mid-iteration, apparently same issue happens in
the fib6 core. From Jiayuan Chen.
4) Add mutex to guard refcount in synproxy infrastructure, since
concurrent hook {un}registration can happen.
From Fernando Fernandez Mancera.
5) Bail out if IRC conntrack helper fails to parse a command, do not
try parsing using other command handlers, from Florian Westphal.
This fixes a possible out-of-bound read.
6) Possible use-after-free in nft_tunnel by releasing template dst
after all references has been dropped, from Tristan Madani.
7) Ignore conntrack template in nft_ct, from Jiayuan Chen.
8) Missing skb_ensure_writable() in ebt_snat, Yiming Qian.
9) Remove multi-register byteorder support, this allows for kernel
stack info leak, from Florian Westphal.
* tag 'nf-26-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: nft_byteorder: remove multi-register support
netfilter: bridge: make ebt_snat ARP rewrite writable
netfilter: nft_ct: bail out on template ct in get eval
netfilter: nft_tunnel: fix use-after-free on object destroy
netfilter: conntrack_irc: fix possible out-of-bounds read
netfilter: synproxy: add mutex to guard hook reference counting
netfilter: nft_fib_ipv6: bail out of sibling walk if rt got unlinked
ipvs: clear the svc scheduler ptr early on edit
netfilter: xt_NFQUEUE: prefer raw_smp_processor_id
====================
Link: https://patch.msgid.link/20260601115923.433946-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
syzbot reported a weird reqsk->rsk_refcnt underflow in
__inet_csk_reqsk_queue_drop().
The captured reqsk_put() in __inet_csk_reqsk_queue_drop()
is called only when it successfully removes reqsk from ehash.
Moreover, reqsk_timer_handler() calls another reqsk_put()
after that.
This indicates that the reqsk was missing both refcnts for
ehash and the timer itself.
Since all the syzbot reports had PREEMPT_RT enabled, the only
possible scenario is that reqsk_queue_hash_req() is preempted
after mod_timer() and before refcount_set(), and then the timer
triggered after 1s aborts the reqsk due to its listener's close().
Let's wrap mod_timer() and refcount_set() with
preempt_disable_nested() and preempt_enable_nested().
Note that inet_ehash_insert() holds the normal spin_lock()
(mutex in PREEMPT_RT), so it must be called outside of
preempt_disable_nested(), but this is fine.
The lookup path just ignores 0 sk_refcnt entries in ehash
and tries to create another reqsk, but this will fail at
inet_ehash_insert().
[0]:
refcount_t: underflow; use-after-free.
WARNING: lib/refcount.c:28 at refcount_warn_saturate+0xb2/0x110 lib/refcount.c:28, CPU#0: ktimers/0/16
Modules linked in:
CPU: 0 UID: 0 PID: 16 Comm: ktimers/0 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:refcount_warn_saturate+0xb2/0x110 lib/refcount.c:28
Code: e4 7d d1 0a 67 48 0f b9 3a eb 4a e8 38 3d 23 fd 48 8d 3d e1 7d d1 0a 67 48 0f b9 3a eb 37 e8 25 3d 23 fd 48 8d 3d de 7d d1 0a <67> 48 0f b9 3a eb 24 e8 12 3d 23 fd 48 8d 3d db 7d d1 0a 67 48 0f
RSP: 0000:ffffc90000157948 EFLAGS: 00010246
RAX: ffffffff84a1301b RBX: 0000000000000003 RCX: ffff88801ca98000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffffffff8f72ae00
RBP: ffffffff99ae3b01 R08: ffff88801ca98000 R09: 0000000000000005
R10: 0000000000000100 R11: 0000000000000004 R12: ffff8880425ef568
R13: ffff8880425ef4f8 R14: ffff8880425ef578 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888126386000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7b46710e9c CR3: 000000000dbb6000 CR4: 00000000003526f0
Call Trace:
<TASK>
__refcount_sub_and_test include/linux/refcount.h:400 [inline]
__refcount_dec_and_test include/linux/refcount.h:432 [inline]
refcount_dec_and_test include/linux/refcount.h:450 [inline]
reqsk_put include/net/request_sock.h:136 [inline]
__inet_csk_reqsk_queue_drop+0x3ce/0x440 net/ipv4/inet_connection_sock.c:1007
reqsk_timer_handler+0x651/0xdf0 net/ipv4/inet_connection_sock.c:1137
call_timer_fn+0x192/0x5e0 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2374 [inline]
__run_timer_base+0x6a3/0x9f0 kernel/time/timer.c:2386
run_timer_base kernel/time/timer.c:2395 [inline]
run_timer_softirq+0x67/0x170 kernel/time/timer.c:2403
handle_softirqs+0x1de/0x6d0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
run_ktimerd+0x69/0x100 kernel/softirq.c:1151
smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
kthread+0x388/0x470 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: d2d6422f8b ("x86: Allow to enable PREEMPT_RT.")
Reported-by: syzbot+e809069bc15f26300526@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/6a1a7bcf.0a9e871e.332604.000b.GAE@google.com/
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://patch.msgid.link/20260601182101.3183993-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
UDP TX skb->destructor() is sock_wfree(), and UDP holds lock_sock()
only for UDP_CORK / MSG_MORE sendmsg().
Otherwise, sk->sk_write_space() may be read locklessly while SOCKMAP
rewrites sk->sk_write_space().
Let's use WRITE_ONCE() and READ_ONCE() for sk->sk_write_space().
Note that the write side is annotated by commit 2ef2b20cf4
("net: annotate data-races around sk->sk_{data_ready,write_space}").
Fixes: 7b98cd42b0 ("bpf: sockmap: Add UDP support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://patch.msgid.link/20260529193941.3897256-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
devlink relation state is normally released from devl_unregister(), which
calls devlink_rel_put(). This misses devlink instances that get a nested
relation before registration and then fail probe before devl_register() is
reached.
That flow can happen for SFs. The child devlink gets linked to its
parent before registration, then a later probe error calls devlink_free()
directly. Since the instance was never registered, devl_unregister() is not
called and devlink->rel is leaked.
Release any pending relation from devlink_free() as well. The registered
path is unchanged because devl_unregister() already clears devlink->rel
before devlink_free() runs.
Fixes: c137743bce ("devlink: introduce object and nested devlink relationship infra")
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://patch.msgid.link/20260528191411.3270532-1-mbloch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
pppol2tp_ioctl() read sock->sk->sk_user_data directly without any
locks or reference counting. If a controllable sleep was induced during
copy_from_user() (e.g. via a userfaultfd page fault sleep), a concurrent
socket close could trigger pppol2tp_session_close() asynchronously. This
frees the l2tp_session structure via the l2tp_session_del_work workqueue.
Upon resuming, the ioctl thread dereferences the stale session pointer,
resulting in a Use-After-Free (UAF).
Fix this by securely fetching the session reference using the RCU-safe,
refcounted helper pppol2tp_sock_to_session(sk) on entry. This locks the
session's refcount across the sleep. We structured the function to exit
via standard err breaks, guaranteeing that l2tp_session_put() is cleanly
called on all return paths to drop the reference.
To preserve existing behavior we validate the session and its magic
signature only for the specific L2TP commands that require it. This
ensures that generic/unknown ioctls called on an unconnected socket
still return -ENOIOCTLCMD and correctly fall back to generic handlers
(e.g. in sock_do_ioctl()).
Signed-off-by: Lee Jones <lee@kernel.org>
Fixes: fd558d186d ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts")
Link: https://patch.msgid.link/20260527133630.2120612-1-lee@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The second memcpy in lowpan_iphc_mcast_ctx_addr_compress() uses
&data[1] as destination and &ipaddr->s6_addr[11] as source, but
both should be offset by one: &data[2] and &ipaddr->s6_addr[12]
respectively.
This off-by-one has two consequences:
1. data[1] is overwritten with s6_addr[11], corrupting the RIID
field in the compressed multicast address
2. data[5] is never written, so uninitialized kernel stack memory
is transmitted over the network via lowpan_push_hc_data(),
leaking kernel stack contents
The correct inline data layout must match what the decompression
function lowpan_uncompress_multicast_ctx_daddr() expects:
data[0..1] = s6_addr[1..2] (flags/scope + RIID)
data[2..5] = s6_addr[12..15] (group ID)
Also zero-initialize the data array as a defensive measure against
similar bugs in the future.
Fixes: 5609c185f2 ("6lowpan: iphc: add support for stateful compression")
Reported-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Reported-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn>
Reported-by: Ao Wang <wangao@seu.edu.cn>
Reported-by: Xuewei Feng <fengxw06@126.com>
Reported-by: Qi Li <qli01@tsinghua.edu.cn>
Reported-by: Ke Xu <xuke@tsinghua.edu.cn>
Signed-off-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Acked-by: Alexander Aring <aahringo@redhat.com>
Link: https://patch.msgid.link/20260527081806.42747-1-zhaoyz24@mails.tsinghua.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When NEWTFILTER and DELFILTER are run concurrently it is possible to create a
race with an associated action.
Let's illustrate with CPU0 running NEWTFILTER and CPU1 running DELFILTER:
0: mutex_lock() <-- holds the idr lock
0: rcu_read_lock()
0: p = idr_find(idr, index) <-- action p is valid (RCU protects IDR)
0: mutex_unlock() <-- releases the idr lock
1: refcount_dec_and_mutex_lock() <-- refcnt 1->0, mutex held
1: idr_remove(idr, index) <-- Action removed from IDR
1: mutex_unlock() <-- mutex released allowing us to delete the action
1: tcf_action_cleanup(p); kfree(p) <-- Kfrees p immediately, no deferral
0: refcount_inc_not_zero(&p->tcfa_refcnt) <-- ouch, UAF p points to freed memory
This patch fixes the race condition between NEWTFILTER and DELFILTER by
adding struct rcu_head to tc_action used in the deferral and introducing a
call_rcu() in the delete path to defer the final kfree().
Note: this is a revert of commit d7fb60b9ca ("net_sched: get rid of tcfa_rcu")
but also modernization/simplification to directly use kfree_rcu().
Let's illustrate the new restored code path:
0: rcu_read_lock()
1: refcount_dec_and_mutex_lock() <-- refcnt 1->0, mutex held
1: idr_remove(idr, index)
1: mutex_unlock()
1: call_rcu(&p->tcfa_rcu, tcf_action_rcu_free) <-- defer kfree after grace period
0: p = idr_find(idr, index)
0: refcount_inc_not_zero(&p->tcfa_refcnt) <-- fails, refcnt already 0
1: rcu_read_unlock() <-- release so freeing can run after grace period
After CPU1 calls idr_remove(), the object is no longer reachable through the IDR.
CPU0's subsequent idr_find() will return NULL, and even if it still held a
stale pointer, the immediate kfree() is now deferred until after the RCU grace
period, so no UAF can occur.
Fixes: d7fb60b9ca ("net_sched: get rid of tcfa_rcu")
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Reported-by: Kyle Zeng <kylebot@openai.com>
Tested-by: Victor Nogueira <victor@mojatatu.com>
Tested-by: syzbot@syzkaller.appspotmail.com
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Tested-by: Kyle Zeng <kylebot@openai.com>
Reviewed-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20260531160812.68020-1-jhs@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
64bit byteorder conversion is broken when several registers need to be
converted because the source register array advances in steps for 4 bytes
instead of 8:
for (i = ...
src64 = nft_reg_load64(&src[i]);
~~~~~ u32 *src
nft_reg_store64(&dst64[i],
Remove the multi-register support, it has other issues as well:
Pablo points out that commit
caf3ef7468 ("netfilter: nf_tables: prevent OOB access in nft_byteorder_eval")
alters semantics: before the loop operated on registers, i.e.
for ( ... )
dst32[i] = htons((u16)src32[i])
.. but after the patch it will operate on bytes, which makes this
useless to convert e.g. concatenations, which store each compound
in its own register.
Multi-convert of u32 has one theoretical application:
ct mark . meta mark . tcp dport @intervalset
Because ct mark and meta mark are host byte order, use with
intervals has to convert the byteorder for ct/meta mark value
to network byte order (bigendian).
nftables emits this:
[ meta load mark => reg 1 ]
[ byteorder reg 1 = hton(reg 1, 4, 4) ]
[ ct load mark => reg 9 ]
[ byteorder reg 9 = hton(reg 9, 4, 4) ]
...
I.e. two separate calls. Theoretically it could be changed to do:
[ meta load mark => reg 1 ]
[ ct load mark => reg 9 ]
[ byteorder reg 1 = htonl(reg 1, 4, 8) ]
...
But then all it would take to change the set to
meta mark . tcp dport . ct mark
... and we'd be back to two "byteorder" calls. IOW, support to
convert a range of registers is both dysfunctional and dubious.
Simplify this: remove the feature.
Pablo Neira Ayuso points out that nftables before 1.1.0 can generate
incorrect byteorder conversions, see 9fe58952c45a,
"evaluate: skip byteorder conversion for selector smaller than 2 bytes"
in nftables.git). Affected rulesets fail to load with this change and
old userspace due to 'len != size' check.
Fixes: c301f0981f ("netfilter: nf_tables: fix pointer math issue in nft_byteorder_eval()")
Cc: <stable+noautosel@kernel.org> # may break rule load with old nftables versions
Reported-by: Michal Kubecek <mkubecek@suse.cz>
Link: https://lore.kernel.org/netfilter-devel/20240206104336.ctigqpkunom2ufmn@lion.mk-sys.cz/
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The ebtables SNAT target keeps the Ethernet source address rewrite
behind skb_ensure_writable(skb, 0). This is intentional: at the bridge
ebtables hooks the Ethernet header is addressed through
skb_mac_header()/eth_hdr(), while skb->data points at the Ethernet
payload. Asking skb_ensure_writable() for ETH_HLEN bytes would check
the payload, not the Ethernet header, and would reintroduce the small
packet regression fixed by commit 63137bc588.
However, the optional ARP sender hardware address rewrite is different.
It writes through skb_store_bits() at an offset relative to skb->data:
skb_store_bits(skb, sizeof(struct arphdr), info->mac, ETH_ALEN)
skb_header_pointer() only safely reads the ARP header; it does not make
the later sender hardware address range writable. If that range is
still held in a nonlinear skb fragment backed by a splice-imported file
page, skb_store_bits() maps the frag page and copies the new MAC address
directly into it.
Ensure the ARP SHA range is writable before reading the ARP header and
before calling skb_store_bits().
Fixes: 63137bc588 ("netfilter: ebtables: Fixes dropping of small packets in bridge nat")
Reported-by: Yiming Qian <yimingqian591@gmail.com>
Signed-off-by: Yiming Qian <yimingqian591@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
I noticed this issue while looking at a historic syzbot report [1].
A rule like the one below is enough to trigger the bug:
table ip t {
chain pre {
type filter hook prerouting priority raw;
ct zone set 1
ct original saddr 1.2.3.4 accept
}
}
The first expression attaches a per-cpu template ct via
nft_ct_set_zone_eval() (nf_ct_tmpl_alloc -> kzalloc, tuple is all
zero, nf_ct_l3num(ct) == 0). The next expression then calls
nft_ct_get_eval() on the same skb, treats the template as a real ct
and hits the 16-byte memcpy path. With dreg at NFT_REG32_15 this
overflows past struct nft_regs on the kernel stack; with smaller
dreg values it silently clobbers adjacent registers.
Reject template ct at the eval entry and in nft_ct_get_fast_eval(),
mirroring the check nft_ct_set_eval() already has. Additionally,
bound the address copy in NFT_CT_SRC / NFT_CT_DST by priv->len
instead of by nf_ct_l3num(ct): nf_ct_get_tuple() zeroes the tuple
before pkt_to_tuple() fills in only the protocol-relevant leading
bytes, so the trailing bytes of tuple->{src,dst}.u3.all are
well-defined zero. priv->len is validated at rule load, so the
copy size is now bounded by the destination register rather than
by an untrusted field on the conntrack.
[1]: https://syzkaller.appspot.com/bug?id=389cf09cb72926114fce90dc85a2c3231dcb647c
Fixes: 45d9bcda21 ("netfilter: nf_tables: validate len in nft_validate_data_load()")
Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nft_tunnel_obj_destroy() calls metadata_dst_free() which directly
kfree()s the metadata_dst, ignoring the dst_entry refcount. Packets
that took a reference via dst_hold() in nft_tunnel_obj_eval() and
are still queued (e.g. in a netem qdisc) are left with a dangling
pointer. When these packets are eventually dequeued, dst_release()
operates on freed memory.
Replace metadata_dst_free() with dst_release() so the metadata_dst
is freed only after all references are dropped. The dst subsystem
already handles metadata_dst cleanup in dst_destroy() when
DST_METADATA is set.
Fixes: af308b94a2 ("netfilter: nf_tables: add tunnel support")
Cc: stable@vger.kernel.org
Signed-off-by: Tristan Madani <tristan@talencesecurity.com>
Reviewed-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When parsing fails after we've matched the command string we
should bail out instead of trying to match a different command.
This helper should be deprecated, given prevalence of TLS I doubt it has
any relevance in 2026.
Fixes: 869f37d8e4 ("[NETFILTER]: nf_conntrack/nf_nat: add IRC helper port")
Closes: https://sashiko.dev/#/patchset/20260525182924.28456-1-fw%40strlen.de
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
As the synproxy infrastructure register netfilter hooks on-demand when a
user adds the first iptables target or nftables expression, if done
concurrently they can race each other.
Introduce a mutex to serialize the refcount control blocks access from
both frontends. While a per namespace mutex might be more efficient, it
is not needed for target/expression like SYNPROXY.
Fixes: ad49d86e07 ("netfilter: nf_tables: Add synproxy support")
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This was reported by Sashiko [1].
The RCU walk over rt->fib6_siblings can spin forever if rt is unlinked
mid-iteration: rt->fib6_siblings.next still points into the old ring,
so the loop never meets &rt->fib6_siblings as its terminator.
fib6_purge_rt() always does WRITE_ONCE(rt->fib6_nsiblings, 0) before
list_del_rcu(), so readers can use rt->fib6_nsiblings == 0 as the
detach signal. The same pattern is used in fib6_info_uses_dev() and
rt6_nlmsg_size().
[1]: https://sashiko.dev/#/patchset/20260520023411.391233-1-jiayuan.chen%40linux.dev
Suggested-by: Florian Westphal <fw@strlen.de>
Fixes: 1c32b24c23 ("netfilter: nft_fib_ipv6: switch to fib6_lookup")
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
ip_vs_edit_service() while unbinding the old scheduler clears
the svc->scheduler ptr after the scheduler module initiates
RCU callbacks. This can cause packets to use the old
scheduler at the time when svc->sched_data is already freed
after RCU grace period.
Fix it by clearing the ptr early in ip_vs_unbind_scheduler(),
before the done_service method schedules any RCU callbacks.
Also, if the new scheduler fails to initialize when replacing
the old scheduler, try to restore the old scheduler while still
returning the error code.
Link: https://sashiko.dev/#/patchset/20260519015506.634185-1-rosenp%40gmail.com
Fixes: 05f00505a8 ("ipvs: fix crash if scheduler is changed")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
With PREEMPT_RCU this triggers a splat because smp_processor_id() can be
preempted while inside a RCU critical section. If xt_NFQUEUE target is
invoked via nft_compat_eval() path, we are inside a RCU critical
section.
Just use the raw version instead.
Fixes: 0ca743a559 ("netfilter: nf_tables: add compatibility layer for x_tables")
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Chris Adams reported that preserving insertion order for same-scope
addresses is causing SSH connections to be dropped after stopping a VM
while running NetworkManager.
NetworkManager caches the IPv6 address configuration, when a RA arrives,
it determines the list of addresses to configure and checks if the
addresses are already in the right order in the kernel. If they aren't,
NetworkManager removes and re-adds them to achieve the desired order.
As the order changes, NetworkManager is confused and reconfigures the
addresses on every update. In addition, this would also affect to cloud
tooling that relies on IPv6 addresses order to identify primary and
secondaries addresses.
This reverts commit cb3de96eea.
Fixes: cb3de96eea ("ipv6: preserve insertion order for same-scope addresses")
Reported-by: Chris Adams <linux@cmadams.net>
Closes: https://lore.kernel.org/netdev/20260521135310.GC977@cmadams.net/
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Link: https://patch.msgid.link/20260529112357.5079-1-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'ipsec-2026-05-29' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:
====================
pull request (net): ipsec 2026-05-29
1) xfrm: route MIGRATE notifications to caller's netns
Thread the caller's netns through km_migrate() so that
MIGRATE notifications go to the issuing netns, fixing both the
init_net listener leak and MOBIKE notifications inside
non-init netns. From Maoyi Xie.
2) xfrm: ipcomp: Free destination pages on acomp errors
Move the out_free_req label up so that allocated destination
pages are released on decompression errors, not only on success.
From Herbert Xu.
3) xfrm: Check for underflow in xfrm_state_mtu
Reject configurations that cause xfrm_state_mtu() to underflow,
preventing a negative TFCPAD value from becoming a memset size
that triggers an out-of-bounds write of several terabytes.
From David Ahern.
4) xfrm: ah: use skb_to_full_sk in async output callbacks
Convert the possibly-incomplete skb->sk to a full socket pointer
in async AH callbacks so that a request_sock or timewait_sock
never reaches xfrm_output_resume() downstream consumers.
From Michael Bommarito.
5) Add and revert: esp: fix page frag reference leak on skb_to_sgvec failure
The patch does not fix te issue completely.
6) xfrm: esp: restore combined single-frag length gate
Check the aligned post-trailer combined length against a page limit
in the fast path, preventing skb_page_frag_refill() from falling
back to a page too small for the destination scatterlist.
From Jingguo Tan.
7) xfrm: iptfs: reset runtime state when cloning SAs
Reinitialise the clone's mode_data runtime objects before
publishing it, preventing queued skbs from being freed with
list state copied from the original SA when migration fails.
From Shaomin Chen.
8) xfrm: move policy_bydst RCU sync from per-netns .exit to .pre_exit
Flush policy tables and drain the workqueue in a .pre_exit handler
so that cleanup_net() pays one RCU grace period per batch instead
of one per namespace, fixing stalls at high CLONE_NEWNET rates.
From Usama Arif.
9) xfrm: input: hold netns during deferred transport reinjection
Take a netns reference when queueing deferred transport reinjection
work and drop it after the callback completes, keeping the skb->cb
net pointer valid until the deferred work runs.
From Zhengchuan Liang.
* tag 'ipsec-2026-05-29' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec:
Revert "esp: fix page frag reference leak on skb_to_sgvec failure"
xfrm: input: hold netns during deferred transport reinjection
xfrm: move policy_bydst RCU sync from per-netns .exit to .pre_exit
xfrm: iptfs: reset runtime state when cloning SAs
xfrm: esp: restore combined single-frag length gate
esp: fix page frag reference leak on skb_to_sgvec failure
xfrm: ah: use skb_to_full_sk in async output callbacks
xfrm: Check for underflow in xfrm_state_mtu
xfrm: ipcomp: Free destination pages on acomp errors
xfrm: route MIGRATE notifications to caller's netns
====================
Link: https://patch.msgid.link/20260529092648.3878973-1-steffen.klassert@secunet.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When SKBFL_MANAGED_FRAG_REFS is set, frag pages are not refcounted but
their lifetime is controlled by the attached ubuf_info. To make a copy
of the skb_shared_info, we either should clear the flag and reference
the frags, or keep the flag and have frags unreferenced.
pskb_carve_inside_header() and pskb_carve_inside_nonlinear() don't
follow the rule and thus can leak page references. Let's clear
SKBFL_MANAGED_FRAG_REFS from the original skb to fix it. It's the
simplest way to address it, but there are more performant ways to do
that if it ever becomes a problem.
Link: https://lore.kernel.org/all/20260523085809.26331-1-nvminh232@clc.fitus.edu.vn/
Fixes: 753f1ca4e1 ("net: introduce managed frags infrastructure")
Reported-by: Minh Nguyen <minhnguyen.080505@gmail.com>
Reported-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/1e2086aa69217d7f9c8da3d38f5be7160f1b4cd1.1779993185.git.asml.silence@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Found while auditing the same pattern Sashiko reported in
rt6_fill_node() [1]. Apply the same fix as
commit f8d8ce1b51 ("ipv6: fix possible infinite loop in fib6_info_uses_dev()").
Writers holding tb6_lock can list_del_rcu(&first->fib6_siblings)
without waiting for RCU readers; first->fib6_siblings.next then
still points into the old ring and this softirq-side walker never
reaches &first->fib6_siblings as its terminator. fib6_purge_rt()
always WRITE_ONCE()s first->fib6_nsiblings to 0 before
list_del_rcu(), so an inside-loop check is a reliable detach signal.
[1] https://sashiko.dev/#/patchset/20260526020227.4857-1-jiayuan.chen%40linux.dev
Fixes: d9ccb18f83 ("ipv6: Fix soft lockups in fib6_select_path under high next hop churn")
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260527053133.180695-2-jiayuan.chen@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Sashiko reported this issue [1]. Apply the same fix as
commit f8d8ce1b51 ("ipv6: fix possible infinite loop in fib6_info_uses_dev()").
Writers holding tb6_lock can list_del_rcu(&rt->fib6_siblings)
without waiting for RCU readers; rt->fib6_siblings.next then still
points into the old ring and this softirq-side walker never reaches
&rt->fib6_siblings, causing a CPU stall. fib6_del_route() always
WRITE_ONCE()s rt->fib6_nsiblings to 0 before list_del_rcu(), so an
inside-loop check is a reliable detach signal.
[1] https://sashiko.dev/#/patchset/20260526020227.4857-1-jiayuan.chen%40linux.dev
Fixes: d9ccb18f83 ("ipv6: Fix soft lockups in fib6_select_path under high next hop churn")
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260527053133.180695-1-jiayuan.chen@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When bpf_msg_push_data() inserts data in the middle of a scatterlist
entry, it splits the original entry into a left fragment and a right
fragment.
The right fragment offset is page-local, but the code advances it with
`start`, which is the message-global insertion point. For inserts into a
non-first SG entry, this over-advances the offset and leaves the split
layout inconsistent.
Advance the right fragment offset by the fragment-local delta,
`start - offset`, which matches the length removed from the front of the
original entry.
Fixes: 6fff607e2f ("bpf: sk_msg program helper bpf_msg_push_data")
Cc: stable@kernel.org
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Zhengchuan Liang <zcliangcn@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Yuqi Xu <xuyq21@lenovo.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Link: https://patch.msgid.link/8b129d10566aa3eb43f61a8f9757bcf51707d324.1779636774.git.xuyq21@lenovo.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
virtio_transport_send_pkt_info() allocates or reuses the zerocopy uarg
before entering the send loop, but virtio_transport_alloc_skb() still
fills the skb before it inherits that uarg. When fixed-buffer vectored
zerocopy hits MAX_SKB_FRAGS, io_sg_from_iter() may partially attach
managed frags and return -EMSGSIZE. The rollback path call kfree_skb()
to free an skb that carries SKBFL_MANAGED_FRAG_REFS but no uarg, so
skb_release_data() falls through to ordinary frag unref.
Pass the uarg into virtio_transport_alloc_skb() and bind it immediately
before virtio_transport_fill_skb(). This keeps control or no-payload skbs
untouched while ensuring success and rollback share one lifetime rule.
Fixes: 581512a6dc ("vsock/virtio: MSG_ZEROCOPY flag support")
Signed-off-by: Lin Ma <malin89@huawei.com>
Signed-off-by: Rongzhen Cui <cuirongzhen@huawei.com>
Signed-off-by: Jingguo Tan <tanjingguo@huawei.com>
Acked-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://patch.msgid.link/20260527023301.1075581-1-malin89@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This reverts commit 2982e599ff.
The patch does not fully fix the issue and the Author does
not match the 'Signed-off-by:' tag, so revert it for now.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
- hci_core: Rework hci_dev_do_reset() to use hci_sync functions
- hci_conn: Fix memory leak in hci_le_big_terminate()
- hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close
- hci_sync: Reset device counters in hci_dev_close_sync()
- hci_sync: fix UAF in hci_le_create_cis_sync
- L2CAP: Fix possible crash on l2cap_ecred_conn_rsp
- L2CAP: fix chan ref leak in l2cap_chan_timeout() on !conn
- L2CAP: use chan timer to close channels in cleanup_listen()
- L2CAP: clear chan->ident on ECRED reconfiguration success
- ISO: fix UAF in iso_recv_frame
- ISO: serialize iso_sock_clear_timer with socket lock
- HIDP: fix missing length checks in hidp_input_report()
- 6lowpan: check skb_clone() return value in send_mcast_pkt()
- btusb: Allow firmware re-download when version matches
- hci_qca: Use 100 ms SSR delay for rampatch and NVM loading
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Merge tag 'for-net-2026-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth
Luiz Augusto von Dentz says:
====================
bluetooth pull request for net:
- hci_core: Rework hci_dev_do_reset() to use hci_sync functions
- hci_conn: Fix memory leak in hci_le_big_terminate()
- hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close
- hci_sync: Reset device counters in hci_dev_close_sync()
- hci_sync: fix UAF in hci_le_create_cis_sync
- L2CAP: Fix possible crash on l2cap_ecred_conn_rsp
- L2CAP: fix chan ref leak in l2cap_chan_timeout() on !conn
- L2CAP: use chan timer to close channels in cleanup_listen()
- L2CAP: clear chan->ident on ECRED reconfiguration success
- ISO: fix UAF in iso_recv_frame
- ISO: serialize iso_sock_clear_timer with socket lock
- HIDP: fix missing length checks in hidp_input_report()
- 6lowpan: check skb_clone() return value in send_mcast_pkt()
- btusb: Allow firmware re-download when version matches
- hci_qca: Use 100 ms SSR delay for rampatch and NVM loading
* tag 'for-net-2026-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth:
Bluetooth: hci_sync: Reset device counters in hci_dev_close_sync()
Bluetooth: hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close
Bluetooth: hci_core: Rework hci_dev_do_reset() to use hci_sync functions
Bluetooth: ISO: serialize iso_sock_clear_timer with socket lock
Bluetooth: ISO: fix UAF in iso_recv_frame
Bluetooth: L2CAP: Fix possible crash on l2cap_ecred_conn_rsp
Bluetooth: l2cap: clear chan->ident on ECRED reconfiguration success
Bluetooth: hci_qca: Use 100 ms SSR delay for rampatch and NVM loading
Bluetooth: hci_sync: fix UAF in hci_le_create_cis_sync
Bluetooth: 6lowpan: check skb_clone() return value in send_mcast_pkt()
Bluetooth: btusb: Allow firmware re-download when version matches
Bluetooth: HIDP: fix missing length checks in hidp_input_report()
Bluetooth: L2CAP: use chan timer to close channels in cleanup_listen()
Bluetooth: L2CAP: fix chan ref leak in l2cap_chan_timeout() on !conn
Bluetooth: hci_conn: Fix memory leak in hci_le_big_terminate()
====================
Link: https://patch.msgid.link/20260528131839.462344-1-luiz.dentz@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sctp_wait_for_connect() drops and re-acquires the socket lock while
waiting for the association to reach ESTABLISHED state. During this
window, another thread can peeloff the association to a new socket via
getsockopt(SCTP_SOCKOPT_PEELOFF), changing asoc->base.sk. After
re-acquiring the old socket lock, sctp_wait_for_connect() returns
success without noticing the migration — the caller then accesses
the association under the wrong lock in sctp_datamsg_from_user().
Add the same sk != asoc->base.sk check that sctp_wait_for_sndbuf()
already has, returning an error if the association was migrated while
we slept.
Fixes: 668c9beb90 ("sctp: implement assign_number for sctp_stream_interleave")
Signed-off-by: Zhenghang Xiao <kipreyyy@gmail.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20260527032411.60959-1-kipreyyy@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Current release - regressions:
- netfilter: walk fib6_siblings under RCU
Previous releases - regressions:
- netlink: fix sending unassigned nsid after assigned one
- bridge: fix sleep in atomic context in netlink path
- sched: fix ethx:ingress -> ethy:egress -> ethx:ingress mirred loop
- ipv4: fix net->ipv4.sysctl_local_reserved_ports UaF
- eth: tun: free page on short-frame rejection in tun_xdp_one()
Previous releases - always broken:
- skbuff: fix missing zerocopy reference in pskb_carve helpers
- handshake: drain pending requests at net namespace exit
- ethtool:
- rss: avoid modifying the RSS context response
- module: avoid leaking a netdev ref on module flash errors
- coalesce: cap profile updates at NET_DIM_PARAMS_NUM_PROFILES
- netfilter: fix dst corruption in same register operation
- nfc: hci: fix out-of-bounds read in HCP header parsing
- ipv6: exthdrs: refresh nh pointer after ipv6_hop_jumbo()
- eth: vti: use ip6_tnl.net in vti6_changelink().
- eth: vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu()
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Merge tag 'net-7.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Paolo Abeni:
"This is again significantly bigger than the same point into the
previous cycle, but at least smaller than last week.
I'm not aware of any pending regression for the current cycle.
Including fixes from netfilter.
Current release - regressions:
- netfilter: walk fib6_siblings under RCU
Previous releases - regressions:
- netlink: fix sending unassigned nsid after assigned one
- bridge: fix sleep in atomic context in netlink path
- sched: fix ethx:ingress -> ethy:egress -> ethx:ingress mirred loop
- ipv4: fix net->ipv4.sysctl_local_reserved_ports UaF
- eth: tun: free page on short-frame rejection in tun_xdp_one()
Previous releases - always broken:
- skbuff: fix missing zerocopy reference in pskb_carve helpers
- handshake: drain pending requests at net namespace exit
- ethtool:
- rss: avoid modifying the RSS context response
- module: avoid leaking a netdev ref on module flash errors
- coalesce: cap profile updates at NET_DIM_PARAMS_NUM_PROFILES
- netfilter: fix dst corruption in same register operation
- nfc: hci: fix out-of-bounds read in HCP header parsing
- ipv6: exthdrs: refresh nh pointer after ipv6_hop_jumbo()
- eth:
- vti: use ip6_tnl.net in vti6_changelink().
- vxlan: do not reuse cached ip_hdr() value after
skb_tunnel_check_pmtu()"
* tag 'net-7.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (94 commits)
dpll: zl3073x: make frequency monitor a per-device attribute
dpll: zl3073x: use __dpll_device_change_ntf() and remove change_work
dpll: export __dpll_device_change_ntf() for use under dpll_lock
net/handshake: Drain pending requests at net namespace exit
net/handshake: Verify file-reference balance in submit paths
net/handshake: Close the submit-side sock_hold race
net/handshake: hand off the pinned file reference to accept_doit
net/handshake: Take a long-lived file reference at submit
net/handshake: Pass negative errno through handshake_complete()
nvme-tcp: store negative errno in queue->tls_err
net/handshake: Use spin_lock_bh for hn_lock
net: skbuff: fix missing zerocopy reference in pskb_carve helpers
net: hibmcge: move dma_rmb() after dma_sync_single_for_cpu() in RX path
net: hibmcge: disable Relaxed Ordering to fix RX packet corruption
selftests/tc-testing: Add netem test case exercising loops
selftests/tc-testing: Add mirred test cases exercising loops
net/sched: act_mirred: Fix return code in early mirred redirect error paths
net/sched: act_mirred: Fix blockcast recursion bypass leading to stack overflow
net/sched: Fix ethx:ingress -> ethy:egress -> ethx:ingress mirred loop
net/sched: fix packet loop on netem when duplicate is on
...
Before resetting or closing the device, protocol counters should also be
zeroed.
Fixes: d0b137062b ("Bluetooth: hci_sync: Rework init stages")
Signed-off-by: Heitor Alves de Siqueira <halves@igalia.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Since hci_dev_close_sync() can now be called during the reset path, we
should also set HCI_CMD_DRAIN_WORKQUEUE. This avoids queuing timeouts
while the hdev workqueue is being drained.
Fixes: 877afadad2 ("Bluetooth: When HCI work queue is drained, only queue chained work")
Signed-off-by: Heitor Alves de Siqueira <halves@igalia.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
The current HCI reset function in hci_core.c duplicates most of the work
done by hci_dev_close_sync(), and doesn't handle LE, advertising or
discovery.
Instead of porting these to hci_dev_do_reset(), directly call the
close/open functions from hci_sync to reset the hdev. MGMT now notifies
when a user performs a reset.
Suggested-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Heitor Alves de Siqueira <halves@igalia.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
iso_sock_close() calls iso_sock_clear_timer() before acquiring
lock_sock(sk).
iso_sock_clear_timer() reads iso_pi(sk)->conn twice without the
socket lock held:
if (!iso_pi(sk)->conn)
return;
cancel_delayed_work(&iso_pi(sk)->conn->timeout_work);
Concurrently, iso_conn_del() executes under lock_sock(sk) and calls
iso_chan_del(), which sets iso_pi(sk)->conn to NULL and may result in
the final reference to the connection being dropped:
CPU0 CPU1
---- ----
iso_sock_clear_timer()
if (conn != NULL) ... lock_sock(sk)
iso_chan_del()
iso_pi(sk)->conn = NULL
cancel_delayed_work(conn) /* NULL deref or UAF */
iso_pi(sk)->conn is not stable across the unlock window, causing a
NULL pointer dereference or use-after-free.
Serialize iso_sock_clear_timer() with the socket lock by moving it
inside lock_sock()/release_sock(), matching the pattern used in
iso_conn_del() and all other call sites.
Fixes: ccf74f2390 ("Bluetooth: Add BTPROTO_ISO socket type")
Cc: stable@vger.kernel.org
Signed-off-by: Muhammad Bilal <meatuni001@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
iso_recv_frame reads conn->sk under iso_conn_lock but releases the lock
before using sk, with no reference held. A concurrent iso_sock_kill()
can free sk in that window, causing use-after-free on sk->sk_state and
sock_queue_rcv_skb().
Fix by replacing the bare pointer read with iso_sock_hold(conn), which
calls sock_hold() while the spinlock is held, atomically elevating the
refcount before the lock drops. Add a drop_put label so sock_put() is
called on all exit paths where the hold succeeded.
Fixes: ccf74f2390 ("Bluetooth: Add BTPROTO_ISO socket type")
Cc: stable@vger.kernel.org
Signed-off-by: Muhammad Bilal <meatuni001@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
If dcid is received for an already-assigned destination CID the spec
requires that both channels to be discarded, but calling l2cap_chan_del
may invalidate the tmp cursor created by list_for_each_entry_safe and
in fact it is the wrong procedure as the chan->dcid may be assigned
previously it really needs to be disconnected.
Calling l2cap_chan_clone directly may still lead to l2cap_chan_del so
instead schedule l2cap_chan_timeout with delay 0 to close the channel
asynchronously.
Fixes: 15f02b9105 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
l2cap_ecred_reconf_rsp() returns early on success without clearing
chan->ident. Every other L2CAP response handler (l2cap_ecred_conn_rsp,
l2cap_le_connect_rsp, l2cap_config_rsp) clears chan->ident after a
successful transaction to prevent the channel from matching subsequent
responses with the recycled ident value.
A remote attacker that completed a reconfiguration as the peer can
replay a failure response with the stale ident, causing the kernel to
match and destroy the already-established channel via
l2cap_chan_del(chan, ECONNRESET).
Clear chan->ident for all matching channels on success, and harden the
failure path by using l2cap_chan_hold_unless_zero() consistent with
other L2CAP handlers (l2cap_le_command_rej, __l2cap_get_chan_by_ident).
Fixes: 15f02b9105 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode")
Signed-off-by: Zhenghang Xiao <kipreyyy@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
The arguments to list_splice_init() in handshake_net_exit() are
reversed. The call moves the local empty "requests" list onto
hn->hn_requests, leaving the local list empty, so the subsequent
drain loop runs zero iterations. Pending handshake requests that
had not yet been accepted are not torn down when the net namespace
is destroyed; each one keeps a reference on a socket file and on
the handshake_req allocation.
Pass the source and destination in the documented order
(list_splice_init(list, head) moves list onto head) so the pending
list is transferred to the local scratch list and drained through
handshake_complete().
Fixing the splice direction exposes a list-corruption race. After
the splice each req->hr_list still has non-empty link pointers,
threading the stack-local scratch list rather than hn_requests.
A concurrent handshake_req_cancel() -- for example, from sunrpc's
TLS timeout on a kernel socket whose netns reference was not
taken -- finds the request through the rhashtable, calls
remove_pending(), and sees !list_empty(&req->hr_list).
__remove_pending_locked() then list_del_init()s an entry off the
scratch list while the drain iterates, corrupting it. The same
call arriving after the drain loop has run list_del() on an
entry hits LIST_POISON instead.
Have remove_pending() check HANDSHAKE_F_NET_DRAINING under
hn_lock and report not-found when drain is in progress. The
drain has already taken ownership; handshake_complete()'s existing
test_and_set on HANDSHAKE_F_REQ_COMPLETED still arbitrates
between drain and cancel for who calls the consumer's hp_done. Use
list_del_init() rather than list_del() in the drain so req->hr_list
does not carry LIST_POISON after drain releases the entry.
The DRAINING guard in remove_pending() makes cancel return false,
but cancel still falls through to test_and_set_bit on
HANDSHAKE_F_REQ_COMPLETED and drops the request's hr_file reference.
Without another pin, if that is the last reference, sk_destruct frees
the request while it is still linked on the drain loop's local list.
Pin each request's hr_file under hn_lock before releasing the list,
and drop that drain pin after the loop finishes with the request.
Fixes: 3b3009ea8a ("net/handshake: Create a NETLINK service for handling handshake requests")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Link: https://patch.msgid.link/20260525-handshake-file-pin-v3-8-66c616906ead@oracle.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The new file-reference contract on struct handshake_req is silently
breakable: a missing get_file() at submit or a missing fput() on an
error path leaves the file leaked but does not crash the test, so
the existing absence-of-crash checks pass either way.
Snapshot file_count(filp) before each handshake_req_submit() in
the submit-success, EAGAIN, EBUSY, and cancel tests, and assert
the expected balance after submit and again after cancel. The
already-completed cancel test also asserts the post-complete
balance, which pins down that handshake_complete() drops the
reference and that the subsequent cancel does not double-fput.
The destroy test gets the same treatment before __fput_sync(),
which double-checks that cancel's fput() ran and the only
remaining reference is the one sock_alloc_file() established.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Link: https://patch.msgid.link/20260525-handshake-file-pin-v3-7-66c616906ead@oracle.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
