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79,691 commits

Author SHA1 Message Date
Paul Chaignon
058a0da4f6 bpf: Reject narrower access to pointer ctx fields
commit e09299225d upstream.

The following BPF program, simplified from a syzkaller repro, causes a
kernel warning:

    r0 = *(u8 *)(r1 + 169);
    exit;

With pointer field sk being at offset 168 in __sk_buff. This access is
detected as a narrower read in bpf_skb_is_valid_access because it
doesn't match offsetof(struct __sk_buff, sk). It is therefore allowed
and later proceeds to bpf_convert_ctx_access. Note that for the
"is_narrower_load" case in the convert_ctx_accesses(), the insn->off
is aligned, so the cnt may not be 0 because it matches the
offsetof(struct __sk_buff, sk) in the bpf_convert_ctx_access. However,
the target_size stays 0 and the verifier errors with a kernel warning:

    verifier bug: error during ctx access conversion(1)

This patch fixes that to return a proper "invalid bpf_context access
off=X size=Y" error on the load instruction.

The same issue affects multiple other fields in context structures that
allow narrow access. Some other non-affected fields (for sk_msg,
sk_lookup, and sockopt) were also changed to use bpf_ctx_range_ptr for
consistency.

Note this syzkaller crash was reported in the "Closes" link below, which
used to be about a different bug, fixed in
commit fce7bd8e38 ("bpf/verifier: Handle BPF_LOAD_ACQ instructions
in insn_def_regno()"). Because syzbot somehow confused the two bugs,
the new crash and repro didn't get reported to the mailing list.

Fixes: f96da09473 ("bpf: simplify narrower ctx access")
Fixes: 0df1a55afa ("bpf: Warn on internal verifier errors")
Reported-by: syzbot+0ef84a7bdf5301d4cbec@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=0ef84a7bdf5301d4cbec
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://patch.msgid.link/3b8dcee67ff4296903351a974ddd9c4dca768b64.1753194596.git.paul.chaignon@gmail.com
Signed-off-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-23 11:18:50 +01:00
Tetsuo Handa
cb2a610867 net: can: j1939: j1939_xtp_rx_rts_session_active(): deactivate session upon receiving the second rts
commit 1809c82aa0 upstream.

Since j1939_session_deactivate_activate_next() in j1939_tp_rxtimer() is
called only when the timer is enabled, we need to call
j1939_session_deactivate_activate_next() if we cancelled the timer.
Otherwise, refcount for j1939_session leaks, which will later appear as

| unregister_netdevice: waiting for vcan0 to become free. Usage count = 2.

problem.

Reported-by: syzbot <syzbot+881d65229ca4f9ae8c84@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=881d65229ca4f9ae8c84
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Link: https://patch.msgid.link/b1212653-8fa1-44e1-be9d-12f950fb3a07@I-love.SAKURA.ne.jp
Cc: stable@vger.kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-23 11:18:43 +01:00
Ido Schimmel
bdced577da bridge: mcast: Fix use-after-free during router port configuration
commit 7544f3f5b0 upstream.

The bridge maintains a global list of ports behind which a multicast
router resides. The list is consulted during forwarding to ensure
multicast packets are forwarded to these ports even if the ports are not
member in the matching MDB entry.

When per-VLAN multicast snooping is enabled, the per-port multicast
context is disabled on each port and the port is removed from the global
router port list:

 # ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1
 # ip link add name dummy1 up master br1 type dummy
 # ip link set dev dummy1 type bridge_slave mcast_router 2
 $ bridge -d mdb show | grep router
 router ports on br1: dummy1
 # ip link set dev br1 type bridge mcast_vlan_snooping 1
 $ bridge -d mdb show | grep router

However, the port can be re-added to the global list even when per-VLAN
multicast snooping is enabled:

 # ip link set dev dummy1 type bridge_slave mcast_router 0
 # ip link set dev dummy1 type bridge_slave mcast_router 2
 $ bridge -d mdb show | grep router
 router ports on br1: dummy1

Since commit 4b30ae9adb ("net: bridge: mcast: re-implement
br_multicast_{enable, disable}_port functions"), when per-VLAN multicast
snooping is enabled, multicast disablement on a port will disable the
per-{port, VLAN} multicast contexts and not the per-port one. As a
result, a port will remain in the global router port list even after it
is deleted. This will lead to a use-after-free [1] when the list is
traversed (when adding a new port to the list, for example):

 # ip link del dev dummy1
 # ip link add name dummy2 up master br1 type dummy
 # ip link set dev dummy2 type bridge_slave mcast_router 2

Similarly, stale entries can also be found in the per-VLAN router port
list. When per-VLAN multicast snooping is disabled, the per-{port, VLAN}
contexts are disabled on each port and the port is removed from the
per-VLAN router port list:

 # ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1 mcast_vlan_snooping 1
 # ip link add name dummy1 up master br1 type dummy
 # bridge vlan add vid 2 dev dummy1
 # bridge vlan global set vid 2 dev br1 mcast_snooping 1
 # bridge vlan set vid 2 dev dummy1 mcast_router 2
 $ bridge vlan global show dev br1 vid 2 | grep router
       router ports: dummy1
 # ip link set dev br1 type bridge mcast_vlan_snooping 0
 $ bridge vlan global show dev br1 vid 2 | grep router

However, the port can be re-added to the per-VLAN list even when
per-VLAN multicast snooping is disabled:

 # bridge vlan set vid 2 dev dummy1 mcast_router 0
 # bridge vlan set vid 2 dev dummy1 mcast_router 2
 $ bridge vlan global show dev br1 vid 2 | grep router
       router ports: dummy1

When the VLAN is deleted from the port, the per-{port, VLAN} multicast
context will not be disabled since multicast snooping is not enabled
on the VLAN. As a result, the port will remain in the per-VLAN router
port list even after it is no longer member in the VLAN. This will lead
to a use-after-free [2] when the list is traversed (when adding a new
port to the list, for example):

 # ip link add name dummy2 up master br1 type dummy
 # bridge vlan add vid 2 dev dummy2
 # bridge vlan del vid 2 dev dummy1
 # bridge vlan set vid 2 dev dummy2 mcast_router 2

Fix these issues by removing the port from the relevant (global or
per-VLAN) router port list in br_multicast_port_ctx_deinit(). The
function is invoked during port deletion with the per-port multicast
context and during VLAN deletion with the per-{port, VLAN} multicast
context.

Note that deleting the multicast router timer is not enough as it only
takes care of the temporary multicast router states (1 or 3) and not the
permanent one (2).

[1]
BUG: KASAN: slab-out-of-bounds in br_multicast_add_router.part.0+0x3f1/0x560
Write of size 8 at addr ffff888004a67328 by task ip/384
[...]
Call Trace:
 <TASK>
 dump_stack_lvl+0x6f/0xa0
 print_address_description.constprop.0+0x6f/0x350
 print_report+0x108/0x205
 kasan_report+0xdf/0x110
 br_multicast_add_router.part.0+0x3f1/0x560
 br_multicast_set_port_router+0x74e/0xac0
 br_setport+0xa55/0x1870
 br_port_slave_changelink+0x95/0x120
 __rtnl_newlink+0x5e8/0xa40
 rtnl_newlink+0x627/0xb00
 rtnetlink_rcv_msg+0x6fb/0xb70
 netlink_rcv_skb+0x11f/0x350
 netlink_unicast+0x426/0x710
 netlink_sendmsg+0x75a/0xc20
 __sock_sendmsg+0xc1/0x150
 ____sys_sendmsg+0x5aa/0x7b0
 ___sys_sendmsg+0xfc/0x180
 __sys_sendmsg+0x124/0x1c0
 do_syscall_64+0xbb/0x360
 entry_SYSCALL_64_after_hwframe+0x4b/0x53

[2]
BUG: KASAN: slab-use-after-free in br_multicast_add_router.part.0+0x378/0x560
Read of size 8 at addr ffff888009f00840 by task bridge/391
[...]
Call Trace:
 <TASK>
 dump_stack_lvl+0x6f/0xa0
 print_address_description.constprop.0+0x6f/0x350
 print_report+0x108/0x205
 kasan_report+0xdf/0x110
 br_multicast_add_router.part.0+0x378/0x560
 br_multicast_set_port_router+0x6f9/0xac0
 br_vlan_process_options+0x8b6/0x1430
 br_vlan_rtm_process_one+0x605/0xa30
 br_vlan_rtm_process+0x396/0x4c0
 rtnetlink_rcv_msg+0x2f7/0xb70
 netlink_rcv_skb+0x11f/0x350
 netlink_unicast+0x426/0x710
 netlink_sendmsg+0x75a/0xc20
 __sock_sendmsg+0xc1/0x150
 ____sys_sendmsg+0x5aa/0x7b0
 ___sys_sendmsg+0xfc/0x180
 __sys_sendmsg+0x124/0x1c0
 do_syscall_64+0xbb/0x360
 entry_SYSCALL_64_after_hwframe+0x4b/0x53

Fixes: 2796d846d7 ("net: bridge: vlan: convert mcast router global option to per-vlan entry")
Fixes: 4b30ae9adb ("net: bridge: mcast: re-implement br_multicast_{enable, disable}_port functions")
Reported-by: syzbot+7bfa4b72c6a5da128d32@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/684c18bd.a00a0220.279073.000b.GAE@google.com/T/
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20250619182228.1656906-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-23 11:18:42 +01:00
Eric Dumazet
362e269bb0 net/sched: sch_qfq: do not free existing class in qfq_change_class()
[ Upstream commit 3879cffd9d ]

Fixes qfq_change_class() error case.

cl->qdisc and cl should only be freed if a new class and qdisc
were allocated, or we risk various UAF.

Fixes: 462dbc9101 ("pkt_sched: QFQ Plus: fair-queueing service at DRR cost")
Reported-by: syzbot+07f3f38f723c335f106d@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/6965351d.050a0220.eaf7.00c5.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260112175656.17605-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-23 11:18:39 +01:00
Kuniyuki Iwashima
2684610a9c ipv6: Fix use-after-free in inet6_addr_del().
[ Upstream commit ddf96c393a ]

syzbot reported use-after-free of inet6_ifaddr in
inet6_addr_del(). [0]

The cited commit accidentally moved ipv6_del_addr() for
mngtmpaddr before reading its ifp->flags for temporary
addresses in inet6_addr_del().

Let's move ipv6_del_addr() down to fix the UAF.

[0]:
BUG: KASAN: slab-use-after-free in inet6_addr_del.constprop.0+0x67a/0x6b0 net/ipv6/addrconf.c:3117
Read of size 4 at addr ffff88807b89c86c by task syz.3.1618/9593

CPU: 0 UID: 0 PID: 9593 Comm: syz.3.1618 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 inet6_addr_del.constprop.0+0x67a/0x6b0 net/ipv6/addrconf.c:3117
 addrconf_del_ifaddr+0x11e/0x190 net/ipv6/addrconf.c:3181
 inet6_ioctl+0x1e5/0x2b0 net/ipv6/af_inet6.c:582
 sock_do_ioctl+0x118/0x280 net/socket.c:1254
 sock_ioctl+0x227/0x6b0 net/socket.c:1375
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f164cf8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f164de64038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f164d1e5fa0 RCX: 00007f164cf8f749
RDX: 0000200000000000 RSI: 0000000000008936 RDI: 0000000000000003
RBP: 00007f164d013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f164d1e6038 R14: 00007f164d1e5fa0 R15: 00007ffde15c8288
 </TASK>

Allocated by task 9593:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 poison_kmalloc_redzone mm/kasan/common.c:397 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:414
 kmalloc_noprof include/linux/slab.h:957 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 ipv6_add_addr+0x4e3/0x2010 net/ipv6/addrconf.c:1120
 inet6_addr_add+0x256/0x9b0 net/ipv6/addrconf.c:3050
 addrconf_add_ifaddr+0x1fc/0x450 net/ipv6/addrconf.c:3160
 inet6_ioctl+0x103/0x2b0 net/ipv6/af_inet6.c:580
 sock_do_ioctl+0x118/0x280 net/socket.c:1254
 sock_ioctl+0x227/0x6b0 net/socket.c:1375
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 6099:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2540 [inline]
 slab_free_freelist_hook mm/slub.c:2569 [inline]
 slab_free_bulk mm/slub.c:6696 [inline]
 kmem_cache_free_bulk mm/slub.c:7383 [inline]
 kmem_cache_free_bulk+0x2bf/0x680 mm/slub.c:7362
 kfree_bulk include/linux/slab.h:830 [inline]
 kvfree_rcu_bulk+0x1b7/0x1e0 mm/slab_common.c:1523
 kvfree_rcu_drain_ready mm/slab_common.c:1728 [inline]
 kfree_rcu_monitor+0x1d0/0x2f0 mm/slab_common.c:1801
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Fixes: 00b5b7aab9 ("net/ipv6: delete temporary address if mngtmpaddr is removed or unmanaged")
Reported-by: syzbot+72e610f4f1a930ca9d8a@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/696598e9.050a0220.3be5c5.0009.GAE@google.com/
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260113010538.2019411-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-23 11:18:39 +01:00
Eric Dumazet
aa57bfea46 ipv4: ip_gre: make ipgre_header() robust
[ Upstream commit e67c577d89 ]

Analog to commit db5b4e39c4 ("ip6_gre: make ip6gre_header() robust")

Over the years, syzbot found many ways to crash the kernel
in ipgre_header() [1].

This involves team or bonding drivers ability to dynamically
change their dev->needed_headroom and/or dev->hard_header_len

In this particular crash mld_newpack() allocated an skb
with a too small reserve/headroom, and by the time mld_sendpack()
was called, syzbot managed to attach an ipgre device.

[1]
skbuff: skb_under_panic: text:ffffffff89ea3cb7 len:2030915468 put:2030915372 head:ffff888058b43000 data:ffff887fdfa6e194 tail:0x120 end:0x6c0 dev:team0
 kernel BUG at net/core/skbuff.c:213 !
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 1322 Comm: kworker/1:9 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: mld mld_ifc_work
 RIP: 0010:skb_panic+0x157/0x160 net/core/skbuff.c:213
Call Trace:
 <TASK>
  skb_under_panic net/core/skbuff.c:223 [inline]
  skb_push+0xc3/0xe0 net/core/skbuff.c:2641
  ipgre_header+0x67/0x290 net/ipv4/ip_gre.c:897
  dev_hard_header include/linux/netdevice.h:3436 [inline]
  neigh_connected_output+0x286/0x460 net/core/neighbour.c:1618
  NF_HOOK_COND include/linux/netfilter.h:307 [inline]
  ip6_output+0x340/0x550 net/ipv6/ip6_output.c:247
  NF_HOOK+0x9e/0x380 include/linux/netfilter.h:318
  mld_sendpack+0x8d4/0xe60 net/ipv6/mcast.c:1855
  mld_send_cr net/ipv6/mcast.c:2154 [inline]
  mld_ifc_work+0x83e/0xd60 net/ipv6/mcast.c:2693
  process_one_work kernel/workqueue.c:3257 [inline]
  process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
  worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
  kthread+0x711/0x8a0 kernel/kthread.c:463
  ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Fixes: c544193214 ("GRE: Refactor GRE tunneling code.")
Reported-by: syzbot+7c134e1c3aa3283790b9@syzkaller.appspotmail.com
Closes: https://www.spinics.net/lists/netdev/msg1147302.html
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260108190214.1667040-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-23 11:18:37 +01:00
Eric Dumazet
dfd1f962f2 net: update netdev_lock_{type,name}
[ Upstream commit eb74c19fe1 ]

Add missing entries in netdev_lock_type[] and netdev_lock_name[] :

CAN, MCTP, RAWIP, CAIF, IP6GRE, 6LOWPAN, NETLINK, VSOCKMON,
IEEE802154_MONITOR.

Also add a WARN_ONCE() in netdev_lock_pos() to help future bug hunting
next time a protocol is added without updating these arrays.

Fixes: 1a33e10e4a ("net: partially revert dynamic lockdep key changes")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260108093244.830280-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-23 11:18:37 +01:00
Eric Dumazet
df5ffde966 ip6_tunnel: use skb_vlan_inet_prepare() in __ip6_tnl_rcv()
[ Upstream commit 81c734dae2 ]

Blamed commit did not take care of VLAN encapsulations
as spotted by syzbot [1].

Use skb_vlan_inet_prepare() instead of pskb_inet_may_pull().

[1]
 BUG: KMSAN: uninit-value in __INET_ECN_decapsulate include/net/inet_ecn.h:253 [inline]
 BUG: KMSAN: uninit-value in INET_ECN_decapsulate include/net/inet_ecn.h:275 [inline]
 BUG: KMSAN: uninit-value in IP6_ECN_decapsulate+0x7a8/0x1fa0 include/net/inet_ecn.h:321
  __INET_ECN_decapsulate include/net/inet_ecn.h:253 [inline]
  INET_ECN_decapsulate include/net/inet_ecn.h:275 [inline]
  IP6_ECN_decapsulate+0x7a8/0x1fa0 include/net/inet_ecn.h:321
  ip6ip6_dscp_ecn_decapsulate+0x16f/0x1b0 net/ipv6/ip6_tunnel.c:729
  __ip6_tnl_rcv+0xed9/0x1b50 net/ipv6/ip6_tunnel.c:860
  ip6_tnl_rcv+0xc3/0x100 net/ipv6/ip6_tunnel.c:903
 gre_rcv+0x1529/0x1b90 net/ipv6/ip6_gre.c:-1
  ip6_protocol_deliver_rcu+0x1c89/0x2c60 net/ipv6/ip6_input.c:438
  ip6_input_finish+0x1f4/0x4a0 net/ipv6/ip6_input.c:489
  NF_HOOK include/linux/netfilter.h:318 [inline]
  ip6_input+0x9c/0x330 net/ipv6/ip6_input.c:500
  ip6_mc_input+0x7ca/0xc10 net/ipv6/ip6_input.c:590
  dst_input include/net/dst.h:474 [inline]
  ip6_rcv_finish+0x958/0x990 net/ipv6/ip6_input.c:79
  NF_HOOK include/linux/netfilter.h:318 [inline]
  ipv6_rcv+0xf1/0x3c0 net/ipv6/ip6_input.c:311
  __netif_receive_skb_one_core net/core/dev.c:6139 [inline]
  __netif_receive_skb+0x1df/0xac0 net/core/dev.c:6252
  netif_receive_skb_internal net/core/dev.c:6338 [inline]
  netif_receive_skb+0x57/0x630 net/core/dev.c:6397
  tun_rx_batched+0x1df/0x980 drivers/net/tun.c:1485
  tun_get_user+0x5c0e/0x6c60 drivers/net/tun.c:1953
  tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999
  new_sync_write fs/read_write.c:593 [inline]
  vfs_write+0xbe2/0x15d0 fs/read_write.c:686
  ksys_write fs/read_write.c:738 [inline]
  __do_sys_write fs/read_write.c:749 [inline]
  __se_sys_write fs/read_write.c:746 [inline]
  __x64_sys_write+0x1fb/0x4d0 fs/read_write.c:746
  x64_sys_call+0x30ab/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:2
  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
  do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
  slab_post_alloc_hook mm/slub.c:4960 [inline]
  slab_alloc_node mm/slub.c:5263 [inline]
  kmem_cache_alloc_node_noprof+0x9e7/0x17a0 mm/slub.c:5315
  kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:586
  __alloc_skb+0x805/0x1040 net/core/skbuff.c:690
  alloc_skb include/linux/skbuff.h:1383 [inline]
  alloc_skb_with_frags+0xc5/0xa60 net/core/skbuff.c:6712
  sock_alloc_send_pskb+0xacc/0xc60 net/core/sock.c:2995
  tun_alloc_skb drivers/net/tun.c:1461 [inline]
  tun_get_user+0x1142/0x6c60 drivers/net/tun.c:1794
  tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999
  new_sync_write fs/read_write.c:593 [inline]
  vfs_write+0xbe2/0x15d0 fs/read_write.c:686
  ksys_write fs/read_write.c:738 [inline]
  __do_sys_write fs/read_write.c:749 [inline]
  __se_sys_write fs/read_write.c:746 [inline]
  __x64_sys_write+0x1fb/0x4d0 fs/read_write.c:746
  x64_sys_call+0x30ab/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:2
  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
  do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 6465 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(none)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025

Fixes: 8d975c15c0 ("ip6_tunnel: make sure to pull inner header in __ip6_tnl_rcv()")
Reported-by: syzbot+d4dda070f833dc5dc89a@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/695e88b2.050a0220.1c677c.036d.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260107163109.4188620-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-23 11:18:37 +01:00
Eric Dumazet
6dabb5b89c net: bridge: annotate data-races around fdb->{updated,used}
[ Upstream commit b25a0b4a21 ]

fdb->updated and fdb->used are read and written locklessly.

Add READ_ONCE()/WRITE_ONCE() annotations.

Fixes: 31cbc39b63 ("net: bridge: add option to allow activity notifications for any fdb entries")
Reported-by: syzbot+bfab43087ad57222ce96@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/695e3d74.050a0220.1c677c.035f.GAE@google.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260108093806.834459-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-23 11:18:37 +01:00
Antony Antony
a2a3c7bf2c xfrm: set ipv4 no_pmtu_disc flag only on output sa when direction is set
[ Upstream commit c196def07b ]

The XFRM_STATE_NOPMTUDISC flag is only meaningful for output SAs, but
it was being applied regardless of the SA direction when the sysctl
ip_no_pmtu_disc is enabled. This can unintentionally affect input SAs.

Limit setting XFRM_STATE_NOPMTUDISC to output SAs when the SA direction
is configured.

Closes: https://github.com/strongswan/strongswan/issues/2946
Fixes: a4a87fa4e9 ("xfrm: Add Direction to the SA in or out")
Signed-off-by: Antony Antony <antony.antony@secunet.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-23 11:18:35 +01:00
Jianbo Liu
f93a187c25 xfrm: Fix inner mode lookup in tunnel mode GSO segmentation
[ Upstream commit 3d5221af9c ]

Commit 61fafbee6c ("xfrm: Determine inner GSO type from packet inner
protocol") attempted to fix GSO segmentation by reading the inner
protocol from XFRM_MODE_SKB_CB(skb)->protocol. This was incorrect
because the field holds the inner L4 protocol (TCP/UDP) instead of the
required tunnel protocol. Also, the memory location (shared by
XFRM_SKB_CB(skb) which could be overwritten by xfrm_replay_overflow())
is prone to corruption. This combination caused the kernel to select
the wrong inner mode and get the wrong address family.

The correct value is in xfrm_offload(skb)->proto, which is set from
the outer tunnel header's protocol field by esp[4|6]_gso_encap(). It
is initialized by xfrm[4|6]_tunnel_encap_add() to either IPPROTO_IPIP
or IPPROTO_IPV6, using xfrm_af2proto() and correctly reflects the
inner packet's address family.

Fixes: 61fafbee6c ("xfrm: Determine inner GSO type from packet inner protocol")
Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-23 11:18:35 +01:00
Shardul Bankar
9e3f8fa533 bpf: test_run: Fix ctx leak in bpf_prog_test_run_xdp error path
commit 7f9ee5fc97 upstream.

Fix a memory leak in bpf_prog_test_run_xdp() where the context buffer
allocated by bpf_ctx_init() is not freed when the function returns early
due to a data size check.

On the failing path:
  ctx = bpf_ctx_init(...);
  if (kattr->test.data_size_in - meta_sz < ETH_HLEN)
      return -EINVAL;

The early return bypasses the cleanup label that kfree()s ctx, leading to a
leak detectable by kmemleak under fuzzing. Change the return to jump to the
existing free_ctx label.

Fixes: fe9544ed1a ("bpf: Support specifying linear xdp packet data size for BPF_PROG_TEST_RUN")
Reported-by: BPF Runtime Fuzzer (BRF)
Signed-off-by: Shardul Bankar <shardulsb08@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/20251014120037.1981316-1-shardulsb08@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-17 16:31:29 +01:00
Tetsuo Handa
ba6f0d1832 can: j1939: make j1939_session_activate() fail if device is no longer registered
[ Upstream commit 5d5602236f ]

syzbot is still reporting

  unregister_netdevice: waiting for vcan0 to become free. Usage count = 2

even after commit 93a27b5891 ("can: j1939: add missing calls in
NETDEV_UNREGISTER notification handler") was added. A debug printk() patch
found that j1939_session_activate() can succeed even after
j1939_cancel_active_session() from j1939_netdev_notify(NETDEV_UNREGISTER)
has completed.

Since j1939_cancel_active_session() is processed with the session list lock
held, checking ndev->reg_state in j1939_session_activate() with the session
list lock held can reliably close the race window.

Reported-by: syzbot <syzbot+881d65229ca4f9ae8c84@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=881d65229ca4f9ae8c84
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://patch.msgid.link/b9653191-d479-4c8b-8536-1326d028db5c@I-love.SAKURA.ne.jp
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:28 +01:00
Florian Westphal
14fa3d1927 netfilter: nf_tables: avoid chain re-validation if possible
[ Upstream commit 8e1a1bc4f5 ]

Hamza Mahfooz reports cpu soft lock-ups in
nft_chain_validate():

 watchdog: BUG: soft lockup - CPU#1 stuck for 27s! [iptables-nft-re:37547]
[..]
 RIP: 0010:nft_chain_validate+0xcb/0x110 [nf_tables]
[..]
  nft_immediate_validate+0x36/0x50 [nf_tables]
  nft_chain_validate+0xc9/0x110 [nf_tables]
  nft_immediate_validate+0x36/0x50 [nf_tables]
  nft_chain_validate+0xc9/0x110 [nf_tables]
  nft_immediate_validate+0x36/0x50 [nf_tables]
  nft_chain_validate+0xc9/0x110 [nf_tables]
  nft_immediate_validate+0x36/0x50 [nf_tables]
  nft_chain_validate+0xc9/0x110 [nf_tables]
  nft_immediate_validate+0x36/0x50 [nf_tables]
  nft_chain_validate+0xc9/0x110 [nf_tables]
  nft_immediate_validate+0x36/0x50 [nf_tables]
  nft_chain_validate+0xc9/0x110 [nf_tables]
  nft_table_validate+0x6b/0xb0 [nf_tables]
  nf_tables_validate+0x8b/0xa0 [nf_tables]
  nf_tables_commit+0x1df/0x1eb0 [nf_tables]
[..]

Currently nf_tables will traverse the entire table (chain graph), starting
from the entry points (base chains), exploring all possible paths
(chain jumps).  But there are cases where we could avoid revalidation.

Consider:
1  input -> j2 -> j3
2  input -> j2 -> j3
3  input -> j1 -> j2 -> j3

Then the second rule does not need to revalidate j2, and, by extension j3,
because this was already checked during validation of the first rule.
We need to validate it only for rule 3.

This is needed because chain loop detection also ensures we do not exceed
the jump stack: Just because we know that j2 is cycle free, its last jump
might now exceed the allowed stack size.  We also need to update all
reachable chains with the new largest observed call depth.

Care has to be taken to revalidate even if the chain depth won't be an
issue: chain validation also ensures that expressions are not called from
invalid base chains.  For example, the masquerade expression can only be
called from NAT postrouting base chains.

Therefore we also need to keep record of the base chain context (type,
hooknum) and revalidate if the chain becomes reachable from a different
hook location.

Reported-by: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com>
Closes: https://lore.kernel.org/netfilter-devel/20251118221735.GA5477@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net/
Tested-by: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:28 +01:00
Tetsuo Handa
fb9ef40ccc bpf: Fix reference count leak in bpf_prog_test_run_xdp()
[ Upstream commit ec69daabe4 ]

syzbot is reporting

  unregister_netdevice: waiting for sit0 to become free. Usage count = 2

problem. A debug printk() patch found that a refcount is obtained at
xdp_convert_md_to_buff() from bpf_prog_test_run_xdp().

According to commit ec94670fcb ("bpf: Support specifying ingress via
xdp_md context in BPF_PROG_TEST_RUN"), the refcount obtained by
xdp_convert_md_to_buff() will be released by xdp_convert_buff_to_md().

Therefore, we can consider that the error handling path introduced by
commit 1c19499825 ("bpf: introduce frags support to
bpf_prog_test_run_xdp()") forgot to call xdp_convert_buff_to_md().

Reported-by: syzbot+881d65229ca4f9ae8c84@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=881d65229ca4f9ae8c84
Fixes: 1c19499825 ("bpf: introduce frags support to bpf_prog_test_run_xdp()")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/af090e53-9d9b-4412-8acb-957733b3975c@I-love.SAKURA.ne.jp
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:27 +01:00
Toke Høiland-Jørgensen
6447e697cf bpf, test_run: Subtract size of xdp_frame from allowed metadata size
[ Upstream commit e558cca217 ]

The xdp_frame structure takes up part of the XDP frame headroom,
limiting the size of the metadata. However, in bpf_test_run, we don't
take this into account, which makes it possible for userspace to supply
a metadata size that is too large (taking up the entire headroom).

If userspace supplies such a large metadata size in live packet mode,
the xdp_update_frame_from_buff() call in xdp_test_run_init_page() call
will fail, after which packet transmission proceeds with an
uninitialised frame structure, leading to the usual Bad Stuff.

The commit in the Fixes tag fixed a related bug where the second check
in xdp_update_frame_from_buff() could fail, but did not add any
additional constraints on the metadata size. Complete the fix by adding
an additional check on the metadata size. Reorder the checks slightly to
make the logic clearer and add a comment.

Link: https://lore.kernel.org/r/fa2be179-bad7-4ee3-8668-4903d1853461@hust.edu.cn
Fixes: b6f1f780b3 ("bpf, test_run: Fix packet size check for live packet mode")
Reported-by: Yinhao Hu <dddddd@hust.edu.cn>
Reported-by: Kaiyan Mei <M202472210@hust.edu.cn>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Reviewed-by: Amery Hung <ameryhung@gmail.com>
Link: https://lore.kernel.org/r/20260105114747.1358750-1-toke@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:27 +01:00
Amery Hung
6611a73b29 bpf: Support specifying linear xdp packet data size for BPF_PROG_TEST_RUN
[ Upstream commit fe9544ed1a ]

To test bpf_xdp_pull_data(), an xdp packet containing fragments as well
as free linear data area after xdp->data_end needs to be created.
However, bpf_prog_test_run_xdp() always fills the linear area with
data_in before creating fragments, leaving no space to pull data. This
patch will allow users to specify the linear data size through
ctx->data_end.

Currently, ctx_in->data_end must match data_size_in and will not be the
final ctx->data_end seen by xdp programs. This is because ctx->data_end
is populated according to the xdp_buff passed to test_run. The linear
data area available in an xdp_buff, max_linear_sz, is alawys filled up
before copying data_in into fragments.

This patch will allow users to specify the size of data that goes into
the linear area. When ctx_in->data_end is different from data_size_in,
only ctx_in->data_end bytes of data will be put into the linear area when
creating the xdp_buff.

While ctx_in->data_end will be allowed to be different from data_size_in,
it cannot be larger than the data_size_in as there will be no data to
copy from user space. If it is larger than the maximum linear data area
size, the layout suggested by the user will not be honored. Data beyond
max_linear_sz bytes will still be copied into fragments.

Finally, since it is possible for a NIC to produce a xdp_buff with empty
linear data area, allow it when calling bpf_test_init() from
bpf_prog_test_run_xdp() so that we can test XDP kfuncs with such
xdp_buff. This is done by moving lower-bound check to callers as most of
them already do except bpf_prog_test_run_skb(). The change also fixes a
bug that allows passing an xdp_buff with data < ETH_HLEN. This can
happen when ctx is used and metadata is at least ETH_HLEN.

Signed-off-by: Amery Hung <ameryhung@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20250922233356.3356453-7-ameryhung@gmail.com
Stable-dep-of: e558cca217 ("bpf, test_run: Subtract size of xdp_frame from allowed metadata size")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:27 +01:00
Amery Hung
0eb6e9d3b7 bpf: Make variables in bpf_prog_test_run_xdp less confusing
[ Upstream commit 7eb83bff02 ]

Change the variable naming in bpf_prog_test_run_xdp() to make the
overall logic less confusing. As different modes were added to the
function over the time, some variables got overloaded, making
it hard to understand and changing the code becomes error-prone.

Replace "size" with "linear_sz" where it refers to the size of metadata
and data. If "size" refers to input data size, use test.data_size_in
directly.

Replace "max_data_sz" with "max_linear_sz" to better reflect the fact
that it is the maximum size of metadata and data (i.e., linear_sz). Also,
xdp_rxq.frags_size is always PAGE_SIZE, so just set it directly instead
of subtracting headroom and tailroom and adding them back.

Signed-off-by: Amery Hung <ameryhung@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20250922233356.3356453-6-ameryhung@gmail.com
Stable-dep-of: e558cca217 ("bpf, test_run: Subtract size of xdp_frame from allowed metadata size")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:27 +01:00
Yonghong Song
202c5b915e bpf: Fix an issue in bpf_prog_test_run_xdp when page size greater than 4K
[ Upstream commit 4fc012daf9 ]

The bpf selftest xdp_adjust_tail/xdp_adjust_frags_tail_grow failed on
arm64 with 64KB page:
   xdp_adjust_tail/xdp_adjust_frags_tail_grow:FAIL

In bpf_prog_test_run_xdp(), the xdp->frame_sz is set to 4K, but later on
when constructing frags, with 64K page size, the frag data_len could
be more than 4K. This will cause problems in bpf_xdp_frags_increase_tail().

To fix the failure, the xdp->frame_sz is set to be PAGE_SIZE so kernel
can test different page size properly. With the kernel change, the user
space and bpf prog needs adjustment. Currently, the MAX_SKB_FRAGS default
value is 17, so for 4K page, the maximum packet size will be less than 68K.
To test 64K page, a bigger maximum packet size than 68K is desired. So two
different functions are implemented for subtest xdp_adjust_frags_tail_grow.
Depending on different page size, different data input/output sizes are used
to adapt with different page size.

Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20250612035032.2207498-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Stable-dep-of: e558cca217 ("bpf, test_run: Subtract size of xdp_frame from allowed metadata size")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:27 +01:00
Eric Dumazet
dd6ccec088 arp: do not assume dev_hard_header() does not change skb->head
[ Upstream commit c92510f5e3 ]

arp_create() is the only dev_hard_header() caller
making assumption about skb->head being unchanged.

A recent commit broke this assumption.

Initialize @arp pointer after dev_hard_header() call.

Fixes: db5b4e39c4 ("ip6_gre: make ip6gre_header() robust")
Reported-by: syzbot+58b44a770a1585795351@syzkaller.appspotmail.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260107212250.384552-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:25 +01:00
Xiang Mei
43497313d0 net/sched: sch_qfq: Fix NULL deref when deactivating inactive aggregate in qfq_reset
[ Upstream commit c1d73b1480 ]

`qfq_class->leaf_qdisc->q.qlen > 0` does not imply that the class
itself is active.

Two qfq_class objects may point to the same leaf_qdisc. This happens
when:

1. one QFQ qdisc is attached to the dev as the root qdisc, and

2. another QFQ qdisc is temporarily referenced (e.g., via qdisc_get()
/ qdisc_put()) and is pending to be destroyed, as in function
tc_new_tfilter.

When packets are enqueued through the root QFQ qdisc, the shared
leaf_qdisc->q.qlen increases. At the same time, the second QFQ
qdisc triggers qdisc_put and qdisc_destroy: the qdisc enters
qfq_reset() with its own q->q.qlen == 0, but its class's leaf
qdisc->q.qlen > 0. Therefore, the qfq_reset would wrongly deactivate
an inactive aggregate and trigger a null-deref in qfq_deactivate_agg:

[    0.903172] BUG: kernel NULL pointer dereference, address: 0000000000000000
[    0.903571] #PF: supervisor write access in kernel mode
[    0.903860] #PF: error_code(0x0002) - not-present page
[    0.904177] PGD 10299b067 P4D 10299b067 PUD 10299c067 PMD 0
[    0.904502] Oops: Oops: 0002 [#1] SMP NOPTI
[    0.904737] CPU: 0 UID: 0 PID: 135 Comm: exploit Not tainted 6.19.0-rc3+ #2 NONE
[    0.905157] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.17.0-0-gb52ca86e094d-prebuilt.qemu.org 04/01/2014
[    0.905754] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:992 (discriminator 2) include/linux/list.h:1006 (discriminator 2) net/sched/sch_qfq.c:1367 (discriminator 2) net/sched/sch_qfq.c:1393 (discriminator 2))
[    0.906046] Code: 0f 84 4d 01 00 00 48 89 70 18 8b 4b 10 48 c7 c2 ff ff ff ff 48 8b 78 08 48 d3 e2 48 21 f2 48 2b 13 48 8b 30 48 d3 ea 8b 4b 18 0

Code starting with the faulting instruction
===========================================
   0:	0f 84 4d 01 00 00    	je     0x153
   6:	48 89 70 18          	mov    %rsi,0x18(%rax)
   a:	8b 4b 10             	mov    0x10(%rbx),%ecx
   d:	48 c7 c2 ff ff ff ff 	mov    $0xffffffffffffffff,%rdx
  14:	48 8b 78 08          	mov    0x8(%rax),%rdi
  18:	48 d3 e2             	shl    %cl,%rdx
  1b:	48 21 f2             	and    %rsi,%rdx
  1e:	48 2b 13             	sub    (%rbx),%rdx
  21:	48 8b 30             	mov    (%rax),%rsi
  24:	48 d3 ea             	shr    %cl,%rdx
  27:	8b 4b 18             	mov    0x18(%rbx),%ecx
	...
[    0.907095] RSP: 0018:ffffc900004a39a0 EFLAGS: 00010246
[    0.907368] RAX: ffff8881043a0880 RBX: ffff888102953340 RCX: 0000000000000000
[    0.907723] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[    0.908100] RBP: ffff888102952180 R08: 0000000000000000 R09: 0000000000000000
[    0.908451] R10: ffff8881043a0000 R11: 0000000000000000 R12: ffff888102952000
[    0.908804] R13: ffff888102952180 R14: ffff8881043a0ad8 R15: ffff8881043a0880
[    0.909179] FS:  000000002a1a0380(0000) GS:ffff888196d8d000(0000) knlGS:0000000000000000
[    0.909572] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    0.909857] CR2: 0000000000000000 CR3: 0000000102993002 CR4: 0000000000772ef0
[    0.910247] PKRU: 55555554
[    0.910391] Call Trace:
[    0.910527]  <TASK>
[    0.910638]  qfq_reset_qdisc (net/sched/sch_qfq.c:357 net/sched/sch_qfq.c:1485)
[    0.910826]  qdisc_reset (include/linux/skbuff.h:2195 include/linux/skbuff.h:2501 include/linux/skbuff.h:3424 include/linux/skbuff.h:3430 net/sched/sch_generic.c:1036)
[    0.911040]  __qdisc_destroy (net/sched/sch_generic.c:1076)
[    0.911236]  tc_new_tfilter (net/sched/cls_api.c:2447)
[    0.911447]  rtnetlink_rcv_msg (net/core/rtnetlink.c:6958)
[    0.911663]  ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6861)
[    0.911894]  netlink_rcv_skb (net/netlink/af_netlink.c:2550)
[    0.912100]  netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)
[    0.912296]  ? __alloc_skb (net/core/skbuff.c:706)
[    0.912484]  netlink_sendmsg (net/netlink/af_netlink.c:1894)
[    0.912682]  sock_write_iter (net/socket.c:727 (discriminator 1) net/socket.c:742 (discriminator 1) net/socket.c:1195 (discriminator 1))
[    0.912880]  vfs_write (fs/read_write.c:593 fs/read_write.c:686)
[    0.913077]  ksys_write (fs/read_write.c:738)
[    0.913252]  do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1))
[    0.913438]  entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131)
[    0.913687] RIP: 0033:0x424c34
[    0.913844] Code: 89 02 48 c7 c0 ff ff ff ff eb bd 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 80 3d 2d 44 09 00 00 74 13 b8 01 00 00 00 0f 05 9

Code starting with the faulting instruction
===========================================
   0:	89 02                	mov    %eax,(%rdx)
   2:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
   9:	eb bd                	jmp    0xffffffffffffffc8
   b:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
  12:	00 00 00
  15:	90                   	nop
  16:	f3 0f 1e fa          	endbr64
  1a:	80 3d 2d 44 09 00 00 	cmpb   $0x0,0x9442d(%rip)        # 0x9444e
  21:	74 13                	je     0x36
  23:	b8 01 00 00 00       	mov    $0x1,%eax
  28:	0f 05                	syscall
  2a:	09                   	.byte 0x9
[    0.914807] RSP: 002b:00007ffea1938b78 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[    0.915197] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000424c34
[    0.915556] RDX: 000000000000003c RSI: 000000002af378c0 RDI: 0000000000000003
[    0.915912] RBP: 00007ffea1938bc0 R08: 00000000004b8820 R09: 0000000000000000
[    0.916297] R10: 0000000000000001 R11: 0000000000000202 R12: 00007ffea1938d28
[    0.916652] R13: 00007ffea1938d38 R14: 00000000004b3828 R15: 0000000000000001
[    0.917039]  </TASK>
[    0.917158] Modules linked in:
[    0.917316] CR2: 0000000000000000
[    0.917484] ---[ end trace 0000000000000000 ]---
[    0.917717] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:992 (discriminator 2) include/linux/list.h:1006 (discriminator 2) net/sched/sch_qfq.c:1367 (discriminator 2) net/sched/sch_qfq.c:1393 (discriminator 2))
[    0.917978] Code: 0f 84 4d 01 00 00 48 89 70 18 8b 4b 10 48 c7 c2 ff ff ff ff 48 8b 78 08 48 d3 e2 48 21 f2 48 2b 13 48 8b 30 48 d3 ea 8b 4b 18 0

Code starting with the faulting instruction
===========================================
   0:	0f 84 4d 01 00 00    	je     0x153
   6:	48 89 70 18          	mov    %rsi,0x18(%rax)
   a:	8b 4b 10             	mov    0x10(%rbx),%ecx
   d:	48 c7 c2 ff ff ff ff 	mov    $0xffffffffffffffff,%rdx
  14:	48 8b 78 08          	mov    0x8(%rax),%rdi
  18:	48 d3 e2             	shl    %cl,%rdx
  1b:	48 21 f2             	and    %rsi,%rdx
  1e:	48 2b 13             	sub    (%rbx),%rdx
  21:	48 8b 30             	mov    (%rax),%rsi
  24:	48 d3 ea             	shr    %cl,%rdx
  27:	8b 4b 18             	mov    0x18(%rbx),%ecx
	...
[    0.918902] RSP: 0018:ffffc900004a39a0 EFLAGS: 00010246
[    0.919198] RAX: ffff8881043a0880 RBX: ffff888102953340 RCX: 0000000000000000
[    0.919559] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[    0.919908] RBP: ffff888102952180 R08: 0000000000000000 R09: 0000000000000000
[    0.920289] R10: ffff8881043a0000 R11: 0000000000000000 R12: ffff888102952000
[    0.920648] R13: ffff888102952180 R14: ffff8881043a0ad8 R15: ffff8881043a0880
[    0.921014] FS:  000000002a1a0380(0000) GS:ffff888196d8d000(0000) knlGS:0000000000000000
[    0.921424] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    0.921710] CR2: 0000000000000000 CR3: 0000000102993002 CR4: 0000000000772ef0
[    0.922097] PKRU: 55555554
[    0.922240] Kernel panic - not syncing: Fatal exception
[    0.922590] Kernel Offset: disabled

Fixes: 0545a30377 ("pkt_sched: QFQ - quick fair queue scheduler")
Signed-off-by: Xiang Mei <xmei5@asu.edu>
Link: https://patch.msgid.link/20260106034100.1780779-1-xmei5@asu.edu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:25 +01:00
Mohammad Heib
3264881431 net: fix memory leak in skb_segment_list for GRO packets
[ Upstream commit 238e03d046 ]

When skb_segment_list() is called during packet forwarding, it handles
packets that were aggregated by the GRO engine.

Historically, the segmentation logic in skb_segment_list assumes that
individual segments are split from a parent SKB and may need to carry
their own socket memory accounting. Accordingly, the code transfers
truesize from the parent to the newly created segments.

Prior to commit ed4cccef64 ("gro: fix ownership transfer"), this
truesize subtraction in skb_segment_list() was valid because fragments
still carry a reference to the original socket.

However, commit ed4cccef64 ("gro: fix ownership transfer") changed
this behavior by ensuring that fraglist entries are explicitly
orphaned (skb->sk = NULL) to prevent illegal orphaning later in the
stack. This change meant that the entire socket memory charge remained
with the head SKB, but the corresponding accounting logic in
skb_segment_list() was never updated.

As a result, the current code unconditionally adds each fragment's
truesize to delta_truesize and subtracts it from the parent SKB. Since
the fragments are no longer charged to the socket, this subtraction
results in an effective under-count of memory when the head is freed.
This causes sk_wmem_alloc to remain non-zero, preventing socket
destruction and leading to a persistent memory leak.

The leak can be observed via KMEMLEAK when tearing down the networking
environment:

unreferenced object 0xffff8881e6eb9100 (size 2048):
  comm "ping", pid 6720, jiffies 4295492526
  backtrace:
    kmem_cache_alloc_noprof+0x5c6/0x800
    sk_prot_alloc+0x5b/0x220
    sk_alloc+0x35/0xa00
    inet6_create.part.0+0x303/0x10d0
    __sock_create+0x248/0x640
    __sys_socket+0x11b/0x1d0

Since skb_segment_list() is exclusively used for SKB_GSO_FRAGLIST
packets constructed by GRO, the truesize adjustment is removed.

The call to skb_release_head_state() must be preserved. As documented in
commit cf673ed0e0 ("net: fix fraglist segmentation reference count
leak"), it is still required to correctly drop references to SKB
extensions that may be overwritten during __copy_skb_header().

Fixes: ed4cccef64 ("gro: fix ownership transfer")
Signed-off-by: Mohammad Heib <mheib@redhat.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260104213101.352887-1-mheib@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:24 +01:00
Michal Luczaj
6762937a8b vsock: Make accept()ed sockets use custom setsockopt()
[ Upstream commit ce5e612dd4 ]

SO_ZEROCOPY handling in vsock_connectible_setsockopt() does not get called
on accept()ed sockets due to a missing flag. Flip it.

Fixes: e0718bd82e ("vsock: enable setting SO_ZEROCOPY")
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Link: https://patch.msgid.link/20251229-vsock-child-sock-custom-sockopt-v2-1-64778d6c4f88@rbox.co
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:24 +01:00
Weiming Shi
005671c60f net: sock: fix hardened usercopy panic in sock_recv_errqueue
[ Upstream commit 2a71a1a8d0 ]

skbuff_fclone_cache was created without defining a usercopy region,
[1] unlike skbuff_head_cache which properly whitelists the cb[] field.
[2] This causes a usercopy BUG() when CONFIG_HARDENED_USERCOPY is
enabled and the kernel attempts to copy sk_buff.cb data to userspace
via sock_recv_errqueue() -> put_cmsg().

The crash occurs when: 1. TCP allocates an skb using alloc_skb_fclone()
   (from skbuff_fclone_cache) [1]
2. The skb is cloned via skb_clone() using the pre-allocated fclone
[3] 3. The cloned skb is queued to sk_error_queue for timestamp
reporting 4. Userspace reads the error queue via recvmsg(MSG_ERRQUEUE)
5. sock_recv_errqueue() calls put_cmsg() to copy serr->ee from skb->cb
[4] 6. __check_heap_object() fails because skbuff_fclone_cache has no
   usercopy whitelist [5]

When cloned skbs allocated from skbuff_fclone_cache are used in the
socket error queue, accessing the sock_exterr_skb structure in skb->cb
via put_cmsg() triggers a usercopy hardening violation:

[    5.379589] usercopy: Kernel memory exposure attempt detected from SLUB object 'skbuff_fclone_cache' (offset 296, size 16)!
[    5.382796] kernel BUG at mm/usercopy.c:102!
[    5.383923] Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
[    5.384903] CPU: 1 UID: 0 PID: 138 Comm: poc_put_cmsg Not tainted 6.12.57 #7
[    5.384903] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[    5.384903] RIP: 0010:usercopy_abort+0x6c/0x80
[    5.384903] Code: 1a 86 51 48 c7 c2 40 15 1a 86 41 52 48 c7 c7 c0 15 1a 86 48 0f 45 d6 48 c7 c6 80 15 1a 86 48 89 c1 49 0f 45 f3 e8 84 27 88 ff <0f> 0b 490
[    5.384903] RSP: 0018:ffffc900006f77a8 EFLAGS: 00010246
[    5.384903] RAX: 000000000000006f RBX: ffff88800f0ad2a8 RCX: 1ffffffff0f72e74
[    5.384903] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff87b973a0
[    5.384903] RBP: 0000000000000010 R08: 0000000000000000 R09: fffffbfff0f72e74
[    5.384903] R10: 0000000000000003 R11: 79706f6372657375 R12: 0000000000000001
[    5.384903] R13: ffff88800f0ad2b8 R14: ffffea00003c2b40 R15: ffffea00003c2b00
[    5.384903] FS:  0000000011bc4380(0000) GS:ffff8880bf100000(0000) knlGS:0000000000000000
[    5.384903] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    5.384903] CR2: 000056aa3b8e5fe4 CR3: 000000000ea26004 CR4: 0000000000770ef0
[    5.384903] PKRU: 55555554
[    5.384903] Call Trace:
[    5.384903]  <TASK>
[    5.384903]  __check_heap_object+0x9a/0xd0
[    5.384903]  __check_object_size+0x46c/0x690
[    5.384903]  put_cmsg+0x129/0x5e0
[    5.384903]  sock_recv_errqueue+0x22f/0x380
[    5.384903]  tls_sw_recvmsg+0x7ed/0x1960
[    5.384903]  ? srso_alias_return_thunk+0x5/0xfbef5
[    5.384903]  ? schedule+0x6d/0x270
[    5.384903]  ? srso_alias_return_thunk+0x5/0xfbef5
[    5.384903]  ? mutex_unlock+0x81/0xd0
[    5.384903]  ? __pfx_mutex_unlock+0x10/0x10
[    5.384903]  ? __pfx_tls_sw_recvmsg+0x10/0x10
[    5.384903]  ? _raw_spin_lock_irqsave+0x8f/0xf0
[    5.384903]  ? _raw_read_unlock_irqrestore+0x20/0x40
[    5.384903]  ? srso_alias_return_thunk+0x5/0xfbef5

The crash offset 296 corresponds to skb2->cb within skbuff_fclones:
  - sizeof(struct sk_buff) = 232 - offsetof(struct sk_buff, cb) = 40 -
  offset of skb2.cb in fclones = 232 + 40 = 272 - crash offset 296 =
  272 + 24 (inside sock_exterr_skb.ee)

This patch uses a local stack variable as a bounce buffer to avoid the hardened usercopy check failure.

[1] https://elixir.bootlin.com/linux/v6.12.62/source/net/ipv4/tcp.c#L885
[2] https://elixir.bootlin.com/linux/v6.12.62/source/net/core/skbuff.c#L5104
[3] https://elixir.bootlin.com/linux/v6.12.62/source/net/core/skbuff.c#L5566
[4] https://elixir.bootlin.com/linux/v6.12.62/source/net/core/skbuff.c#L5491
[5] https://elixir.bootlin.com/linux/v6.12.62/source/mm/slub.c#L5719

Fixes: 6d07d1cd30 ("usercopy: Restrict non-usercopy caches to size 0")
Reported-by: Xiang Mei <xmei5@asu.edu>
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251223203534.1392218-2-bestswngs@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:23 +01:00
yuan.gao
50f65526b3 inet: ping: Fix icmp out counting
[ Upstream commit 4c0856c225 ]

When the ping program uses an IPPROTO_ICMP socket to send ICMP_ECHO
messages, ICMP_MIB_OUTMSGS is counted twice.

    ping_v4_sendmsg
      ping_v4_push_pending_frames
        ip_push_pending_frames
          ip_finish_skb
            __ip_make_skb
              icmp_out_count(net, icmp_type); // first count
      icmp_out_count(sock_net(sk), user_icmph.type); // second count

However, when the ping program uses an IPPROTO_RAW socket,
ICMP_MIB_OUTMSGS is counted correctly only once.

Therefore, the first count should be removed.

Fixes: c319b4d76b ("net: ipv4: add IPPROTO_ICMP socket kind")
Signed-off-by: yuan.gao <yuan.gao@ucloud.cn>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20251224063145.3615282-1-yuan.gao@ucloud.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:23 +01:00
Alexandre Knecht
269c9283ff bridge: fix C-VLAN preservation in 802.1ad vlan_tunnel egress
[ Upstream commit 3128df6be1 ]

When using an 802.1ad bridge with vlan_tunnel, the C-VLAN tag is
incorrectly stripped from frames during egress processing.

br_handle_egress_vlan_tunnel() uses skb_vlan_pop() to remove the S-VLAN
from hwaccel before VXLAN encapsulation. However, skb_vlan_pop() also
moves any "next" VLAN from the payload into hwaccel:

    /* move next vlan tag to hw accel tag */
    __skb_vlan_pop(skb, &vlan_tci);
    __vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci);

For QinQ frames where the C-VLAN sits in the payload, this moves it to
hwaccel where it gets lost during VXLAN encapsulation.

Fix by calling __vlan_hwaccel_clear_tag() directly, which clears only
the hwaccel S-VLAN and leaves the payload untouched.

This path is only taken when vlan_tunnel is enabled and tunnel_info
is configured, so 802.1Q bridges are unaffected.

Tested with 802.1ad bridge + VXLAN vlan_tunnel, verified C-VLAN
preserved in VXLAN payload via tcpdump.

Fixes: 11538d039a ("bridge: vlan dst_metadata hooks in ingress and egress paths")
Signed-off-by: Alexandre Knecht <knecht.alexandre@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20251228020057.2788865-1-knecht.alexandre@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:23 +01:00
Fernando Fernandez Mancera
26a82dce2b netfilter: nf_conncount: update last_gc only when GC has been performed
[ Upstream commit 7811ba4524 ]

Currently last_gc is being updated everytime a new connection is
tracked, that means that it is updated even if a GC wasn't performed.
With a sufficiently high packet rate, it is possible to always bypass
the GC, causing the list to grow infinitely.

Update the last_gc value only when a GC has been actually performed.

Fixes: d265929930 ("netfilter: nf_conncount: reduce unnecessary GC")
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:22 +01:00
Zilin Guan
e1a436981a netfilter: nf_tables: fix memory leak in nf_tables_newrule()
[ Upstream commit d077e8119d ]

In nf_tables_newrule(), if nft_use_inc() fails, the function jumps to
the err_release_rule label without freeing the allocated flow, leading
to a memory leak.

Fix this by adding a new label err_destroy_flow and jumping to it when
nft_use_inc() fails. This ensures that the flow is properly released
in this error case.

Fixes: 1689f25924 ("netfilter: nf_tables: report use refcount overflow")
Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:22 +01:00
Fernando Fernandez Mancera
dd42e23b6d netfilter: nft_synproxy: avoid possible data-race on update operation
[ Upstream commit 36a3200575 ]

During nft_synproxy eval we are reading nf_synproxy_info struct which
can be modified on update operation concurrently. As nf_synproxy_info
struct fits in 32 bits, use READ_ONCE/WRITE_ONCE annotations.

Fixes: ee394f96ad ("netfilter: nft_synproxy: add synproxy stateful object support")
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:22 +01:00
Florian Westphal
16b4508e87 netfilter: nft_set_pipapo: fix range overlap detection
[ Upstream commit 7711f4bb4b ]

set->klen has to be used, not sizeof().  The latter only compares a
single register but a full check of the entire key is needed.

Example:
table ip t {
        map s {
                typeof iifname . ip saddr : verdict
                flags interval
        }
}

nft add element t s '{ "lo" . 10.0.0.0/24 : drop }' # no error, expected
nft add element t s '{ "lo" . 10.0.0.0/24 : drop }' # no error, expected
nft add element t s '{ "lo" . 10.0.0.0/8 : drop }' # bug: no error

The 3rd 'add element' should be rejected via -ENOTEMPTY, not -EEXIST,
so userspace / nft can report an error to the user.

The latter is only correct for the 2nd case (re-add of existing element).

As-is, userspace is told that the command was successful, but no elements were
added.

After this patch, 3rd command gives:
Error: Could not process rule: File exists
add element t s { "lo" . 127.0.0.0/8 . "lo"  : drop }
                  ^^^^^^^^^^^^^^^^^^^^^^^^^

Fixes: 0eb4b5ee33 ("netfilter: nft_set_pipapo: Separate partial and complete overlap cases on insertion")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17 16:31:22 +01:00
Kuniyuki Iwashima
f09cd20935 tls: Use __sk_dst_get() and dst_dev_rcu() in get_netdev_for_sock().
commit c65f27b9c3 upstream.

get_netdev_for_sock() is called during setsockopt(),
so not under RCU.

Using sk_dst_get(sk)->dev could trigger UAF.

Let's use __sk_dst_get() and dst_dev_rcu().

Note that the only ->ndo_sk_get_lower_dev() user is
bond_sk_get_lower_dev(), which uses RCU.

Fixes: e8f6979981 ("net/tls: Add generic NIC offload infrastructure")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/20250916214758.650211-6-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ Keerthana: Backport to v6.12.y ]
Signed-off-by: Keerthana K <keerthana.kalyanasundaram@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-17 16:31:18 +01:00
Ilya Dryomov
6f468f6ff2 libceph: make calc_target() set t->paused, not just clear it
commit c0fe2994f9 upstream.

Currently calc_target() clears t->paused if the request shouldn't be
paused anymore, but doesn't ever set t->paused even though it's able to
determine when the request should be paused.  Setting t->paused is left
to __submit_request() which is fine for regular requests but doesn't
work for linger requests -- since __submit_request() doesn't operate
on linger requests, there is nowhere for lreq->t.paused to be set.
One consequence of this is that watches don't get reestablished on
paused -> unpaused transitions in cases where requests have been paused
long enough for the (paused) unwatch request to time out and for the
subsequent (re)watch request to enter the paused state.  On top of the
watch not getting reestablished, rbd_reregister_watch() gets stuck with
rbd_dev->watch_mutex held:

  rbd_register_watch
    __rbd_register_watch
      ceph_osdc_watch
        linger_reg_commit_wait

It's waiting for lreq->reg_commit_wait to be completed, but for that to
happen the respective request needs to end up on need_resend_linger list
and be kicked when requests are unpaused.  There is no chance for that
if the request in question is never marked paused in the first place.

The fact that rbd_dev->watch_mutex remains taken out forever then
prevents the image from getting unmapped -- "rbd unmap" would inevitably
hang in D state on an attempt to grab the mutex.

Cc: stable@vger.kernel.org
Reported-by: Raphael Zimmer <raphael.zimmer@tu-ilmenau.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-17 16:31:18 +01:00
Sam Edwards
e94075e950 libceph: reset sparse-read state in osd_fault()
commit 11194b416e upstream.

When a fault occurs, the connection is abandoned, reestablished, and any
pending operations are retried. The OSD client tracks the progress of a
sparse-read reply using a separate state machine, largely independent of
the messenger's state.

If a connection is lost mid-payload or the sparse-read state machine
returns an error, the sparse-read state is not reset. The OSD client
will then interpret the beginning of a new reply as the continuation of
the old one. If this makes the sparse-read machinery enter a failure
state, it may never recover, producing loops like:

  libceph:  [0] got 0 extents
  libceph: data len 142248331 != extent len 0
  libceph: osd0 (1)...:6801 socket error on read
  libceph: data len 142248331 != extent len 0
  libceph: osd0 (1)...:6801 socket error on read

Therefore, reset the sparse-read state in osd_fault(), ensuring retries
start from a clean state.

Cc: stable@vger.kernel.org
Fixes: f628d79997 ("libceph: add sparse read support to OSD client")
Signed-off-by: Sam Edwards <CFSworks@gmail.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-17 16:31:18 +01:00
Ilya Dryomov
d2c4a5f699 libceph: return the handler error from mon_handle_auth_done()
commit e84b48d31b upstream.

Currently any error from ceph_auth_handle_reply_done() is propagated
via finish_auth() but isn't returned from mon_handle_auth_done().  This
results in higher layers learning that (despite the monitor considering
us to be successfully authenticated) something went wrong in the
authentication phase and reacting accordingly, but msgr2 still trying
to proceed with establishing the session in the background.  In the
case of secure mode this can trigger a WARN in setup_crypto() and later
lead to a NULL pointer dereference inside of prepare_auth_signature().

Cc: stable@vger.kernel.org
Fixes: cd1a677cad ("libceph, ceph: implement msgr2.1 protocol (crc and secure modes)")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-17 16:31:17 +01:00
Tuo Li
c4c2152a85 libceph: make free_choose_arg_map() resilient to partial allocation
commit e3fe30e576 upstream.

free_choose_arg_map() may dereference a NULL pointer if its caller fails
after a partial allocation.

For example, in decode_choose_args(), if allocation of arg_map->args
fails, execution jumps to the fail label and free_choose_arg_map() is
called. Since arg_map->size is updated to a non-zero value before memory
allocation, free_choose_arg_map() will iterate over arg_map->args and
dereference a NULL pointer.

To prevent this potential NULL pointer dereference and make
free_choose_arg_map() more resilient, add checks for pointers before
iterating.

Cc: stable@vger.kernel.org
Co-authored-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Tuo Li <islituo@gmail.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-17 16:31:17 +01:00
Ilya Dryomov
6c6cec3db3 libceph: replace overzealous BUG_ON in osdmap_apply_incremental()
commit e00c3f71b5 upstream.

If the osdmap is (maliciously) corrupted such that the incremental
osdmap epoch is different from what is expected, there is no need to
BUG.  Instead, just declare the incremental osdmap to be invalid.

Cc: stable@vger.kernel.org
Reported-by: ziming zhang <ezrakiez@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-17 16:31:17 +01:00
ziming zhang
2802ef3380 libceph: prevent potential out-of-bounds reads in handle_auth_done()
commit 818156caff upstream.

Perform an explicit bounds check on payload_len to avoid a possible
out-of-bounds access in the callout.

[ idryomov: changelog ]

Cc: stable@vger.kernel.org
Signed-off-by: ziming zhang <ezrakiez@gmail.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-17 16:31:17 +01:00
Johannes Berg
f94f95b817 wifi: mac80211: restore non-chanctx injection behaviour
commit d594cc6f2c upstream.

During the transition to use channel contexts throughout, the
ability to do injection while in monitor mode concurrent with
another interface was lost, since the (virtual) monitor won't
have a chanctx assigned in this scenario.

It's harder to fix drivers that actually transitioned to using
channel contexts themselves, such as mt76, but it's easy to do
those that are (still) just using the emulation. Do that.

Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=218763
Reported-and-tested-by: Oscar Alfonso Diaz <oscar.alfonso.diaz@gmail.com>
Fixes: 0a44dfc070 ("wifi: mac80211: simplify non-chanctx drivers")
Link: https://patch.msgid.link/20251216105242.18366-2-johannes@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-17 16:31:17 +01:00
Eric Dumazet
024f71a57d wifi: avoid kernel-infoleak from struct iw_point
commit 21cbf883d0 upstream.

struct iw_point has a 32bit hole on 64bit arches.

struct iw_point {
  void __user   *pointer;       /* Pointer to the data  (in user space) */
  __u16         length;         /* number of fields or size in bytes */
  __u16         flags;          /* Optional params */
};

Make sure to zero the structure to avoid disclosing 32bits of kernel data
to user space.

Fixes: 87de87d5e4 ("wext: Dispatch and handle compat ioctls entirely in net/wireless/wext.c")
Reported-by: syzbot+bfc7323743ca6dbcc3d3@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/695f83f3.050a0220.1c677c.0392.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260108101927.857582-1-edumazet@google.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-17 16:31:17 +01:00
Thadeu Lima de Souza Cascardo
4888e1dcc3 net: Remove RTNL dance for SIOCBRADDIF and SIOCBRDELIF.
commit ed3ba9b6e2 upstream.

SIOCBRDELIF is passed to dev_ioctl() first and later forwarded to
br_ioctl_call(), which causes unnecessary RTNL dance and the splat
below [0] under RTNL pressure.

Let's say Thread A is trying to detach a device from a bridge and
Thread B is trying to remove the bridge.

In dev_ioctl(), Thread A bumps the bridge device's refcnt by
netdev_hold() and releases RTNL because the following br_ioctl_call()
also re-acquires RTNL.

In the race window, Thread B could acquire RTNL and try to remove
the bridge device.  Then, rtnl_unlock() by Thread B will release RTNL
and wait for netdev_put() by Thread A.

Thread A, however, must hold RTNL after the unlock in dev_ifsioc(),
which may take long under RTNL pressure, resulting in the splat by
Thread B.

  Thread A (SIOCBRDELIF)           Thread B (SIOCBRDELBR)
  ----------------------           ----------------------
  sock_ioctl                       sock_ioctl
  `- sock_do_ioctl                 `- br_ioctl_call
     `- dev_ioctl                     `- br_ioctl_stub
        |- rtnl_lock                     |
        |- dev_ifsioc                    '
        '  |- dev = __dev_get_by_name(...)
           |- netdev_hold(dev, ...)      .
       /   |- rtnl_unlock  ------.       |
       |   |- br_ioctl_call       `--->  |- rtnl_lock
  Race |   |  `- br_ioctl_stub           |- br_del_bridge
  Window   |     |                       |  |- dev = __dev_get_by_name(...)
       |   |     |  May take long        |  `- br_dev_delete(dev, ...)
       |   |     |  under RTNL pressure  |     `- unregister_netdevice_queue(dev, ...)
       |   |     |               |       `- rtnl_unlock
       \   |     |- rtnl_lock  <-'          `- netdev_run_todo
           |     |- ...                        `- netdev_run_todo
           |     `- rtnl_unlock                   |- __rtnl_unlock
           |                                      |- netdev_wait_allrefs_any
           |- netdev_put(dev, ...)  <----------------'
                                                Wait refcnt decrement
                                                and log splat below

To avoid blocking SIOCBRDELBR unnecessarily, let's not call
dev_ioctl() for SIOCBRADDIF and SIOCBRDELIF.

In the dev_ioctl() path, we do the following:

  1. Copy struct ifreq by get_user_ifreq in sock_do_ioctl()
  2. Check CAP_NET_ADMIN in dev_ioctl()
  3. Call dev_load() in dev_ioctl()
  4. Fetch the master dev from ifr.ifr_name in dev_ifsioc()

3. can be done by request_module() in br_ioctl_call(), so we move
1., 2., and 4. to br_ioctl_stub().

Note that 2. is also checked later in add_del_if(), but it's better
performed before RTNL.

SIOCBRADDIF and SIOCBRDELIF have been processed in dev_ioctl() since
the pre-git era, and there seems to be no specific reason to process
them there.

[0]:
unregister_netdevice: waiting for wpan3 to become free. Usage count = 2
ref_tracker: wpan3@ffff8880662d8608 has 1/1 users at
     __netdev_tracker_alloc include/linux/netdevice.h:4282 [inline]
     netdev_hold include/linux/netdevice.h:4311 [inline]
     dev_ifsioc+0xc6a/0x1160 net/core/dev_ioctl.c:624
     dev_ioctl+0x255/0x10c0 net/core/dev_ioctl.c:826
     sock_do_ioctl+0x1ca/0x260 net/socket.c:1213
     sock_ioctl+0x23a/0x6c0 net/socket.c:1318
     vfs_ioctl fs/ioctl.c:51 [inline]
     __do_sys_ioctl fs/ioctl.c:906 [inline]
     __se_sys_ioctl fs/ioctl.c:892 [inline]
     __x64_sys_ioctl+0x1a4/0x210 fs/ioctl.c:892
     do_syscall_x64 arch/x86/entry/common.c:52 [inline]
     do_syscall_64+0xcb/0x250 arch/x86/entry/common.c:83
     entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fixes: 893b195875 ("net: bridge: fix ioctl locking")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Reported-by: yan kang <kangyan91@outlook.com>
Reported-by: yue sun <samsun1006219@gmail.com>
Closes: https://lore.kernel.org/netdev/SY8P300MB0421225D54EB92762AE8F0F2A1D32@SY8P300MB0421.AUSP300.PROD.OUTLOOK.COM/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20250316192851.19781-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
[cascardo: fixed conflict at dev_ifsioc]
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-11 15:25:21 +01:00
Jouni Malinen
7b240a8935 wifi: mac80211: Discard Beacon frames to non-broadcast address
[ Upstream commit 193d18f605 ]

Beacon frames are required to be sent to the broadcast address, see IEEE
Std 802.11-2020, 11.1.3.1 ("The Address 1 field of the Beacon .. frame
shall be set to the broadcast address"). A unicast Beacon frame might be
used as a targeted attack to get one of the associated STAs to do
something (e.g., using CSA to move it to another channel). As such, it
is better have strict filtering for this on the received side and
discard all Beacon frames that are sent to an unexpected address.

This is even more important for cases where beacon protection is used.
The current implementation in mac80211 is correctly discarding unicast
Beacon frames if the Protected Frame bit in the Frame Control field is
set to 0. However, if that bit is set to 1, the logic used for checking
for configured BIGTK(s) does not actually work. If the driver does not
have logic for dropping unicast Beacon frames with Protected Frame bit
1, these frames would be accepted in mac80211 processing as valid Beacon
frames even though they are not protected. This would allow beacon
protection to be bypassed. While the logic for checking beacon
protection could be extended to cover this corner case, a more generic
check for discard all Beacon frames based on A1=unicast address covers
this without needing additional changes.

Address all these issues by dropping received Beacon frames if they are
sent to a non-broadcast address.

Cc: stable@vger.kernel.org
Fixes: af2d14b01c ("mac80211: Beacon protection using the new BIGTK (STA)")
Signed-off-by: Jouni Malinen <jouni.malinen@oss.qualcomm.com>
Link: https://patch.msgid.link/20251215151134.104501-1-jouni.malinen@oss.qualcomm.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
[ changed RX_DROP to RX_DROP_MONITOR ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-11 15:25:20 +01:00
Paolo Abeni
1c7c3a9314 mptcp: ensure context reset on disconnect()
[ Upstream commit 86730ac255 ]

After the blamed commit below, if the MPC subflow is already in TCP_CLOSE
status or has fallback to TCP at mptcp_disconnect() time,
mptcp_do_fastclose() skips setting the `send_fastclose flag` and the later
__mptcp_close_ssk() does not reset anymore the related subflow context.

Any later connection will be created with both the `request_mptcp` flag
and the msk-level fallback status off (it is unconditionally cleared at
MPTCP disconnect time), leading to a warning in subflow_data_ready():

  WARNING: CPU: 26 PID: 8996 at net/mptcp/subflow.c:1519 subflow_data_ready (net/mptcp/subflow.c:1519 (discriminator 13))
  Modules linked in:
  CPU: 26 UID: 0 PID: 8996 Comm: syz.22.39 Not tainted 6.18.0-rc7-05427-g11fc074f6c36 #1 PREEMPT(voluntary)
  Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
  RIP: 0010:subflow_data_ready (net/mptcp/subflow.c:1519 (discriminator 13))
  Code: 90 0f 0b 90 90 e9 04 fe ff ff e8 b7 1e f5 fe 89 ee bf 07 00 00 00 e8 db 19 f5 fe 83 fd 07 0f 84 35 ff ff ff e8 9d 1e f5 fe 90 <0f> 0b 90 e9 27 ff ff ff e8 8f 1e f5 fe 4c 89 e7 48 89 de e8 14 09
  RSP: 0018:ffffc9002646fb30 EFLAGS: 00010293
  RAX: 0000000000000000 RBX: ffff88813b218000 RCX: ffffffff825c8435
  RDX: ffff8881300b3580 RSI: ffffffff825c8443 RDI: 0000000000000005
  RBP: 000000000000000b R08: ffffffff825c8435 R09: 000000000000000b
  R10: 0000000000000005 R11: 0000000000000007 R12: ffff888131ac0000
  R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
  FS:  00007f88330af6c0(0000) GS:ffff888a93dd2000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f88330aefe8 CR3: 000000010ff59000 CR4: 0000000000350ef0
  Call Trace:
   <TASK>
   tcp_data_ready (net/ipv4/tcp_input.c:5356)
   tcp_data_queue (net/ipv4/tcp_input.c:5445)
   tcp_rcv_state_process (net/ipv4/tcp_input.c:7165)
   tcp_v4_do_rcv (net/ipv4/tcp_ipv4.c:1955)
   __release_sock (include/net/sock.h:1158 (discriminator 6) net/core/sock.c:3180 (discriminator 6))
   release_sock (net/core/sock.c:3737)
   mptcp_sendmsg (net/mptcp/protocol.c:1763 net/mptcp/protocol.c:1857)
   inet_sendmsg (net/ipv4/af_inet.c:853 (discriminator 7))
   __sys_sendto (net/socket.c:727 (discriminator 15) net/socket.c:742 (discriminator 15) net/socket.c:2244 (discriminator 15))
   __x64_sys_sendto (net/socket.c:2247)
   do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1))
   entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
  RIP: 0033:0x7f883326702d

Address the issue setting an explicit `fastclosing` flag at fastclose
time, and checking such flag after mptcp_do_fastclose().

Fixes: ae15506024 ("mptcp: fix duplicate reset on fastclose")
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/20251212-net-mptcp-subflow_data_ready-warn-v1-2-d1f9fd1c36c8@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
[ Adjust context ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-11 15:25:20 +01:00
Paolo Abeni
79f80a7a47 mptcp: fallback earlier on simult connection
[ Upstream commit 71154bbe49 ]

Syzkaller reports a simult-connect race leading to inconsistent fallback
status:

  WARNING: CPU: 3 PID: 33 at net/mptcp/subflow.c:1515 subflow_data_ready+0x40b/0x7c0 net/mptcp/subflow.c:1515
  Modules linked in:
  CPU: 3 UID: 0 PID: 33 Comm: ksoftirqd/3 Not tainted syzkaller #0 PREEMPT(full)
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
  RIP: 0010:subflow_data_ready+0x40b/0x7c0 net/mptcp/subflow.c:1515
  Code: 89 ee e8 78 61 3c f6 40 84 ed 75 21 e8 8e 66 3c f6 44 89 fe bf 07 00 00 00 e8 c1 61 3c f6 41 83 ff 07 74 09 e8 76 66 3c f6 90 <0f> 0b 90 e8 6d 66 3c f6 48 89 df e8 e5 ad ff ff 31 ff 89 c5 89 c6
  RSP: 0018:ffffc900006cf338 EFLAGS: 00010246
  RAX: 0000000000000000 RBX: ffff888031acd100 RCX: ffffffff8b7f2abf
  RDX: ffff88801e6ea440 RSI: ffffffff8b7f2aca RDI: 0000000000000005
  RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000007
  R10: 0000000000000004 R11: 0000000000002c10 R12: ffff88802ba69900
  R13: 1ffff920000d9e67 R14: ffff888046f81800 R15: 0000000000000004
  FS:  0000000000000000(0000) GS:ffff8880d69bc000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000560fc0ca1670 CR3: 0000000032c3a000 CR4: 0000000000352ef0
  Call Trace:
   <TASK>
   tcp_data_queue+0x13b0/0x4f90 net/ipv4/tcp_input.c:5197
   tcp_rcv_state_process+0xfdf/0x4ec0 net/ipv4/tcp_input.c:6922
   tcp_v6_do_rcv+0x492/0x1740 net/ipv6/tcp_ipv6.c:1672
   tcp_v6_rcv+0x2976/0x41e0 net/ipv6/tcp_ipv6.c:1918
   ip6_protocol_deliver_rcu+0x188/0x1520 net/ipv6/ip6_input.c:438
   ip6_input_finish+0x1e4/0x4b0 net/ipv6/ip6_input.c:489
   NF_HOOK include/linux/netfilter.h:318 [inline]
   NF_HOOK include/linux/netfilter.h:312 [inline]
   ip6_input+0x105/0x2f0 net/ipv6/ip6_input.c:500
   dst_input include/net/dst.h:471 [inline]
   ip6_rcv_finish net/ipv6/ip6_input.c:79 [inline]
   NF_HOOK include/linux/netfilter.h:318 [inline]
   NF_HOOK include/linux/netfilter.h:312 [inline]
   ipv6_rcv+0x264/0x650 net/ipv6/ip6_input.c:311
   __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:5979
   __netif_receive_skb+0x1d/0x160 net/core/dev.c:6092
   process_backlog+0x442/0x15e0 net/core/dev.c:6444
   __napi_poll.constprop.0+0xba/0x550 net/core/dev.c:7494
   napi_poll net/core/dev.c:7557 [inline]
   net_rx_action+0xa9f/0xfe0 net/core/dev.c:7684
   handle_softirqs+0x216/0x8e0 kernel/softirq.c:579
   run_ksoftirqd kernel/softirq.c:968 [inline]
   run_ksoftirqd+0x3a/0x60 kernel/softirq.c:960
   smpboot_thread_fn+0x3f7/0xae0 kernel/smpboot.c:160
   kthread+0x3c2/0x780 kernel/kthread.c:463
   ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
   </TASK>

The TCP subflow can process the simult-connect syn-ack packet after
transitioning to TCP_FIN1 state, bypassing the MPTCP fallback check,
as the sk_state_change() callback is not invoked for * -> FIN_WAIT1
transitions.

That will move the msk socket to an inconsistent status and the next
incoming data will hit the reported splat.

Close the race moving the simult-fallback check at the earliest possible
stage - that is at syn-ack generation time.

About the fixes tags: [2] was supposed to also fix this issue introduced
by [3]. [1] is required as a dependence: it was not explicitly marked as
a fix, but it is one and it has already been backported before [3]. In
other words, this commit should be backported up to [3], including [2]
and [1] if that's not already there.

Fixes: 23e89e8ee7 ("tcp: Don't drop SYN+ACK for simultaneous connect().") [1]
Fixes: 4fd19a3070 ("mptcp: fix inconsistent state on fastopen race") [2]
Fixes: 1e777f39b4 ("mptcp: add MSG_FASTOPEN sendmsg flag support") [3]
Cc: stable@vger.kernel.org
Reported-by: syzbot+0ff6b771b4f7a5bce83b@syzkaller.appspotmail.com
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/586
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/20251212-net-mptcp-subflow_data_ready-warn-v1-1-d1f9fd1c36c8@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
[ adapted mptcp_try_fallback() call ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-11 15:25:19 +01:00
Eric Dumazet
5d1be493d1 net: use dst_dev_rcu() in sk_setup_caps()
[ Upstream commit 99a2ace61b ]

Use RCU to protect accesses to dst->dev from sk_setup_caps()
and sk_dst_gso_max_size().

Also use dst_dev_rcu() in ip6_dst_mtu_maybe_forward(),
and ip_dst_mtu_maybe_forward().

ip4_dst_hoplimit() can use dst_dev_net_rcu().

Fixes: 4a6ce2b6f2 ("net: introduce a new function dst_dev_put()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250828195823.3958522-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[Harshit: Backport to 6.12.y, resolve conflict due to missing commit:
22d6c9eebf ("net: Unexport shared functions for DCCP.")  in 6.12.y]
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-08 10:15:01 +01:00
Eric Dumazet
8e8d6bf686 ipv6: adopt dst_dev() helper
[ Upstream commit 1caf272972 ]

Use the new helper as a step to deal with potential dst->dev races.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250630121934.3399505-9-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[Harshit: Backport to 6.12.y, pulled this is a prerequisite]
Stable-dep-of: 99a2ace61b ("net: use dst_dev_rcu() in sk_setup_caps()")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-08 10:15:01 +01:00
Justin Iurman
1e28e7701b net: ipv6: ioam6: use consistent dst names
[ Upstream commit d55acb9732 ]

Be consistent and use the same terminology as other lwt users: orig_dst
is the dst_entry before the transformation, while dst is either the
dst_entry in the cache or the dst_entry after the transformation

Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Link: https://patch.msgid.link/20250415112554.23823-2-justin.iurman@uliege.be
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
[Harshit: Backport to 6.12.y]
Stable-dep-of: 99a2ace61b ("net: use dst_dev_rcu() in sk_setup_caps()")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-08 10:15:01 +01:00
Andrii Melnychenko
4ab2cd906e netfilter: nft_ct: add seqadj extension for natted connections
[ Upstream commit 90918e3b64 ]

Sequence adjustment may be required for FTP traffic with PASV/EPSV modes.
due to need to re-write packet payload (IP, port) on the ftp control
connection. This can require changes to the TCP length and expected
seq / ack_seq.

The easiest way to reproduce this issue is with PASV mode.
Example ruleset:
table inet ftp_nat {
        ct helper ftp_helper {
                type "ftp" protocol tcp
                l3proto inet
        }

        chain prerouting {
                type filter hook prerouting priority 0; policy accept;
                tcp dport 21 ct state new ct helper set "ftp_helper"
        }
}
table ip nat {
        chain prerouting {
                type nat hook prerouting priority -100; policy accept;
                tcp dport 21 dnat ip prefix to ip daddr map {
			192.168.100.1 : 192.168.13.2/32 }
        }

        chain postrouting {
                type nat hook postrouting priority 100 ; policy accept;
                tcp sport 21 snat ip prefix to ip saddr map {
			192.168.13.2 : 192.168.100.1/32 }
        }
}

Note that the ftp helper gets assigned *after* the dnat setup.

The inverse (nat after helper assign) is handled by an existing
check in nf_nat_setup_info() and will not show the problem.

Topoloy:

 +-------------------+     +----------------------------------+
 | FTP: 192.168.13.2 | <-> | NAT: 192.168.13.3, 192.168.100.1 |
 +-------------------+     +----------------------------------+
                                      |
                         +-----------------------+
                         | Client: 192.168.100.2 |
                         +-----------------------+

ftp nat changes do not work as expected in this case:
Connected to 192.168.100.1.
[..]
ftp> epsv
EPSV/EPRT on IPv4 off.
ftp> ls
227 Entering passive mode (192,168,100,1,209,129).
421 Service not available, remote server has closed connection.

Kernel logs:
Missing nfct_seqadj_ext_add() setup call
WARNING: CPU: 1 PID: 0 at net/netfilter/nf_conntrack_seqadj.c:41
[..]
 __nf_nat_mangle_tcp_packet+0x100/0x160 [nf_nat]
 nf_nat_ftp+0x142/0x280 [nf_nat_ftp]
 help+0x4d1/0x880 [nf_conntrack_ftp]
 nf_confirm+0x122/0x2e0 [nf_conntrack]
 nf_hook_slow+0x3c/0xb0
 ..

Fix this by adding the required extension when a conntrack helper is assigned
to a connection that has a nat binding.

Fixes: 1a64edf54f ("netfilter: nft_ct: add helper set support")
Signed-off-by: Andrii Melnychenko <a.melnychenko@vyos.io>
Signed-off-by: Florian Westphal <fw@strlen.de>
[Harshit: Clean cherry-pick, apply it to stable-6.12.y]
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-08 10:15:00 +01:00
Joshua Rogers
5f140b5251 svcrdma: bound check rq_pages index in inline path
[ Upstream commit d1bea0ce35 ]

svc_rdma_copy_inline_range indexed rqstp->rq_pages[rc_curpage] without
verifying rc_curpage stays within the allocated page array. Add guards
before the first use and after advancing to a new page.

Fixes: d7cc739726 ("svcrdma: support multiple Read chunks per RPC")
Cc: stable@vger.kernel.org
Signed-off-by: Joshua Rogers <linux@joshua.hu>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[ replaced rqstp->rq_maxpages with ARRAY_SIZE(rqstp->rq_pages) ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-08 10:14:58 +01:00
Matthieu Baerts (NGI0)
984dc07404 mptcp: pm: ignore unknown endpoint flags
[ Upstream commit 0ace3297a7 ]

Before this patch, the kernel was saving any flags set by the userspace,
even unknown ones. This doesn't cause critical issues because the kernel
is only looking at specific ones. But on the other hand, endpoints dumps
could tell the userspace some recent flags seem to be supported on older
kernel versions.

Instead, ignore all unknown flags when parsing them. By doing that, the
userspace can continue to set unsupported flags, but it has a way to
verify what is supported by the kernel.

Note that it sounds better to continue accepting unsupported flags not
to change the behaviour, but also that eases things on the userspace
side by adding "optional" endpoint types only supported by newer kernel
versions without having to deal with the different kernel versions.

A note for the backports: there will be conflicts in mptcp.h on older
versions not having the mentioned flags, the new line should still be
added last, and the '5' needs to be adapted to have the same value as
the last entry.

Fixes: 01cacb00b3 ("mptcp: add netlink-based PM")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20251205-net-mptcp-misc-fixes-6-19-rc1-v1-1-9e4781a6c1b8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ GENMASK(5, 0) => GENMASK(4, 0) + context ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-08 10:14:57 +01:00
Jiri Slaby (SUSE)
2299e3ba12 tty: introduce and use tty_port_tty_vhangup() helper
[ Upstream commit 2b5eac0f8c ]

This code (tty_get -> vhangup -> tty_put) is repeated on few places.
Introduce a helper similar to tty_port_tty_hangup() (asynchronous) to
handle even vhangup (synchronous).

And use it on those places.

In fact, reuse the tty_port_tty_hangup()'s code and call tty_vhangup()
depending on a new bool parameter.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: David Lin <dtwlin@gmail.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alex Elder <elder@kernel.org>
Cc: Oliver Neukum <oneukum@suse.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20250611100319.186924-2-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 74098cc06e ("xhci: dbgtty: fix device unregister: fixup")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-08 10:14:56 +01:00