Commit graph

9 commits

Author SHA1 Message Date
Jason A. Donenfeld
0aceb22a3e wireguard: send: annotate intentional data race in checking empty queue
commit 381a7d453fa2ac5f854a154d3c9b1bbb90c4f94f upstream.

KCSAN reports a race in wg_packet_send_keepalive, which is intentional:

    BUG: KCSAN: data-race in wg_packet_send_keepalive / wg_packet_send_staged_packets

    write to 0xffff88814cd91280 of 8 bytes by task 3194 on cpu 0:
     __skb_queue_head_init include/linux/skbuff.h:2162 [inline]
     skb_queue_splice_init include/linux/skbuff.h:2248 [inline]
     wg_packet_send_staged_packets+0xe5/0xad0 drivers/net/wireguard/send.c:351
     wg_xmit+0x5b8/0x660 drivers/net/wireguard/device.c:218
     __netdev_start_xmit include/linux/netdevice.h:4940 [inline]
     netdev_start_xmit include/linux/netdevice.h:4954 [inline]
     xmit_one net/core/dev.c:3548 [inline]
     dev_hard_start_xmit+0x11b/0x3f0 net/core/dev.c:3564
     __dev_queue_xmit+0xeff/0x1d80 net/core/dev.c:4349
     dev_queue_xmit include/linux/netdevice.h:3134 [inline]
     neigh_connected_output+0x231/0x2a0 net/core/neighbour.c:1592
     neigh_output include/net/neighbour.h:542 [inline]
     ip6_finish_output2+0xa66/0xce0 net/ipv6/ip6_output.c:137
     ip6_finish_output+0x1a5/0x490 net/ipv6/ip6_output.c:222
     NF_HOOK_COND include/linux/netfilter.h:303 [inline]
     ip6_output+0xeb/0x220 net/ipv6/ip6_output.c:243
     dst_output include/net/dst.h:451 [inline]
     NF_HOOK include/linux/netfilter.h:314 [inline]
     ndisc_send_skb+0x4a2/0x670 net/ipv6/ndisc.c:509
     ndisc_send_rs+0x3ab/0x3e0 net/ipv6/ndisc.c:719
     addrconf_dad_completed+0x640/0x8e0 net/ipv6/addrconf.c:4295
     addrconf_dad_work+0x891/0xbc0
     process_one_work kernel/workqueue.c:2633 [inline]
     process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2706
     worker_thread+0x525/0x730 kernel/workqueue.c:2787
     kthread+0x1d7/0x210 kernel/kthread.c:388
     ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
     ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

    read to 0xffff88814cd91280 of 8 bytes by task 3202 on cpu 1:
     skb_queue_empty include/linux/skbuff.h:1798 [inline]
     wg_packet_send_keepalive+0x20/0x100 drivers/net/wireguard/send.c:225
     wg_receive_handshake_packet drivers/net/wireguard/receive.c:186 [inline]
     wg_packet_handshake_receive_worker+0x445/0x5e0 drivers/net/wireguard/receive.c:213
     process_one_work kernel/workqueue.c:2633 [inline]
     process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2706
     worker_thread+0x525/0x730 kernel/workqueue.c:2787
     kthread+0x1d7/0x210 kernel/kthread.c:388
     ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
     ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

    value changed: 0xffff888148fef200 -> 0xffff88814cd91280

Mark this race as intentional by using the skb_queue_empty_lockless()
function rather than skb_queue_empty(), which uses READ_ONCE()
internally to annotate the race.

Cc: stable@vger.kernel.org
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://patch.msgid.link/20240704154517.1572127-5-Jason@zx2c4.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-19 14:19:45 +01:00
Jason A. Donenfeld
6d5a3d273d wireguard: queueing: annotate intentional data race in cpu round robin
commit 2fe3d6d2053c57f2eae5e85ca1656d185ebbe4e8 upstream.

KCSAN reports a race in the CPU round robin function, which, as the
comment points out, is intentional:

    BUG: KCSAN: data-race in wg_packet_send_staged_packets / wg_packet_send_staged_packets

    read to 0xffff88811254eb28 of 4 bytes by task 3160 on cpu 1:
     wg_cpumask_next_online drivers/net/wireguard/queueing.h:127 [inline]
     wg_queue_enqueue_per_device_and_peer drivers/net/wireguard/queueing.h:173 [inline]
     wg_packet_create_data drivers/net/wireguard/send.c:320 [inline]
     wg_packet_send_staged_packets+0x60e/0xac0 drivers/net/wireguard/send.c:388
     wg_packet_send_keepalive+0xe2/0x100 drivers/net/wireguard/send.c:239
     wg_receive_handshake_packet drivers/net/wireguard/receive.c:186 [inline]
     wg_packet_handshake_receive_worker+0x449/0x5f0 drivers/net/wireguard/receive.c:213
     process_one_work kernel/workqueue.c:3248 [inline]
     process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3329
     worker_thread+0x526/0x720 kernel/workqueue.c:3409
     kthread+0x1d1/0x210 kernel/kthread.c:389
     ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
     ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

    write to 0xffff88811254eb28 of 4 bytes by task 3158 on cpu 0:
     wg_cpumask_next_online drivers/net/wireguard/queueing.h:130 [inline]
     wg_queue_enqueue_per_device_and_peer drivers/net/wireguard/queueing.h:173 [inline]
     wg_packet_create_data drivers/net/wireguard/send.c:320 [inline]
     wg_packet_send_staged_packets+0x6e5/0xac0 drivers/net/wireguard/send.c:388
     wg_packet_send_keepalive+0xe2/0x100 drivers/net/wireguard/send.c:239
     wg_receive_handshake_packet drivers/net/wireguard/receive.c:186 [inline]
     wg_packet_handshake_receive_worker+0x449/0x5f0 drivers/net/wireguard/receive.c:213
     process_one_work kernel/workqueue.c:3248 [inline]
     process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3329
     worker_thread+0x526/0x720 kernel/workqueue.c:3409
     kthread+0x1d1/0x210 kernel/kthread.c:389
     ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
     ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

    value changed: 0xffffffff -> 0x00000000

Mark this race as intentional by using READ/WRITE_ONCE().

Cc: stable@vger.kernel.org
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://patch.msgid.link/20240704154517.1572127-4-Jason@zx2c4.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-19 14:19:45 +01:00
Helge Deller
0b1387627a wireguard: allowedips: avoid unaligned 64-bit memory accesses
commit 948f991c62a4018fb81d85804eeab3029c6209f8 upstream.

On the parisc platform, the kernel issues kernel warnings because
swap_endian() tries to load a 128-bit IPv6 address from an unaligned
memory location:

 Kernel: unaligned access to 0x55f4688c in wg_allowedips_insert_v6+0x2c/0x80 [wireguard] (iir 0xf3010df)
 Kernel: unaligned access to 0x55f46884 in wg_allowedips_insert_v6+0x38/0x80 [wireguard] (iir 0xf2010dc)

Avoid such unaligned memory accesses by instead using the
get_unaligned_be64() helper macro.

Signed-off-by: Helge Deller <deller@gmx.de>
[Jason: replace src[8] in original patch with src+8]
Cc: stable@vger.kernel.org
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://patch.msgid.link/20240704154517.1572127-3-Jason@zx2c4.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-19 14:19:45 +01:00
Jason A. Donenfeld
0405673099 wireguard: netlink: access device through ctx instead of peer
[ Upstream commit 71cbd32e3db82ea4a74e3ef9aeeaa6971969c86f ]

The previous commit fixed a bug that led to a NULL peer->device being
dereferenced. It's actually easier and faster performance-wise to
instead get the device from ctx->wg. This semantically makes more sense
too, since ctx->wg->peer_allowedips.seq is compared with
ctx->allowedips_seq, basing them both in ctx. This also acts as a
defence in depth provision against freed peers.

Cc: stable@vger.kernel.org
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 09:22:37 +01:00
Jason A. Donenfeld
27a2180b1e wireguard: netlink: check for dangling peer via is_dead instead of empty list
[ Upstream commit 55b6c738673871c9b0edae05d0c97995c1ff08c4 ]

If all peers are removed via wg_peer_remove_all(), rather than setting
peer_list to empty, the peer is added to a temporary list with a head on
the stack of wg_peer_remove_all(). If a netlink dump is resumed and the
cursored peer is one that has been removed via wg_peer_remove_all(), it
will iterate from that peer and then attempt to dump freed peers.

Fix this by instead checking peer->is_dead, which was explictly created
for this purpose. Also move up the device_update_lock lockdep assertion,
since reading is_dead relies on that.

It can be reproduced by a small script like:

    echo "Setting config..."
    ip link add dev wg0 type wireguard
    wg setconf wg0 /big-config
    (
            while true; do
                    echo "Showing config..."
                    wg showconf wg0 > /dev/null
            done
    ) &
    sleep 4
    wg setconf wg0 <(printf "[Peer]\nPublicKey=$(wg genkey)\n")

Resulting in:

    BUG: KASAN: slab-use-after-free in __lock_acquire+0x182a/0x1b20
    Read of size 8 at addr ffff88811956ec70 by task wg/59
    CPU: 2 PID: 59 Comm: wg Not tainted 6.8.0-rc2-debug+ #5
    Call Trace:
     <TASK>
     dump_stack_lvl+0x47/0x70
     print_address_description.constprop.0+0x2c/0x380
     print_report+0xab/0x250
     kasan_report+0xba/0xf0
     __lock_acquire+0x182a/0x1b20
     lock_acquire+0x191/0x4b0
     down_read+0x80/0x440
     get_peer+0x140/0xcb0
     wg_get_device_dump+0x471/0x1130

Cc: stable@vger.kernel.org
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Reported-by: Lillian Berry <lillian@star-ark.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 09:22:36 +01:00
Nikita Zhandarovich
85f4665d3d wireguard: receive: annotate data-race around receiving_counter.counter
[ Upstream commit bba045dc4d996d03dce6fe45726e78a1a1f6d4c3 ]

Syzkaller with KCSAN identified a data-race issue when accessing
keypair->receiving_counter.counter. Use READ_ONCE() and WRITE_ONCE()
annotations to mark the data race as intentional.

    BUG: KCSAN: data-race in wg_packet_decrypt_worker / wg_packet_rx_poll

    write to 0xffff888107765888 of 8 bytes by interrupt on cpu 0:
     counter_validate drivers/net/wireguard/receive.c:321 [inline]
     wg_packet_rx_poll+0x3ac/0xf00 drivers/net/wireguard/receive.c:461
     __napi_poll+0x60/0x3b0 net/core/dev.c:6536
     napi_poll net/core/dev.c:6605 [inline]
     net_rx_action+0x32b/0x750 net/core/dev.c:6738
     __do_softirq+0xc4/0x279 kernel/softirq.c:553
     do_softirq+0x5e/0x90 kernel/softirq.c:454
     __local_bh_enable_ip+0x64/0x70 kernel/softirq.c:381
     __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
     _raw_spin_unlock_bh+0x36/0x40 kernel/locking/spinlock.c:210
     spin_unlock_bh include/linux/spinlock.h:396 [inline]
     ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline]
     wg_packet_decrypt_worker+0x6c5/0x700 drivers/net/wireguard/receive.c:499
     process_one_work kernel/workqueue.c:2633 [inline]
     ...

    read to 0xffff888107765888 of 8 bytes by task 3196 on cpu 1:
     decrypt_packet drivers/net/wireguard/receive.c:252 [inline]
     wg_packet_decrypt_worker+0x220/0x700 drivers/net/wireguard/receive.c:501
     process_one_work kernel/workqueue.c:2633 [inline]
     process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2706
     worker_thread+0x525/0x730 kernel/workqueue.c:2787
     ...

Fixes: a9e90d9931f3 ("wireguard: noise: separate receive counter from send counter")
Reported-by: syzbot+d1de830e4ecdaac83d89@syzkaller.appspotmail.com
Signed-off-by: Nikita Zhandarovich <n.zhandarovich@fintech.ru>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 08:44:59 +01:00
Ksawlii
0a0cae37b0 Revert "wireguard: use DEV_STATS_INC()"
This reverts commit d1ecdb7757.
2024-11-18 20:09:56 +01:00
Eric Dumazet
d1ecdb7757 wireguard: use DEV_STATS_INC()
[ Upstream commit 93da8d75a66568ba4bb5b14ad2833acd7304cd02 ]

wg_xmit() can be called concurrently, KCSAN reported [1]
some device stats updates can be lost.

Use DEV_STATS_INC() for this unlikely case.

[1]
BUG: KCSAN: data-race in wg_xmit / wg_xmit

read-write to 0xffff888104239160 of 8 bytes by task 1375 on cpu 0:
wg_xmit+0x60f/0x680 drivers/net/wireguard/device.c:231
__netdev_start_xmit include/linux/netdevice.h:4918 [inline]
netdev_start_xmit include/linux/netdevice.h:4932 [inline]
xmit_one net/core/dev.c:3543 [inline]
dev_hard_start_xmit+0x11b/0x3f0 net/core/dev.c:3559
...

read-write to 0xffff888104239160 of 8 bytes by task 1378 on cpu 1:
wg_xmit+0x60f/0x680 drivers/net/wireguard/device.c:231
__netdev_start_xmit include/linux/netdevice.h:4918 [inline]
netdev_start_xmit include/linux/netdevice.h:4932 [inline]
xmit_one net/core/dev.c:3543 [inline]
dev_hard_start_xmit+0x11b/0x3f0 net/core/dev.c:3559
...

v2: also change wg_packet_consume_data_done() (Hangbin Liu)
    and wg_packet_purge_staged_packets()

Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 12:10:54 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00