linux-stable.git/drivers/net/wireguard, branch linux-6.8.y

wireguard: netlink: access device through ctx instead of peer

2024-04-03T13:32:26+00:00

[ 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 
Reviewed-by: Jiri Pirko 
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

wireguard: netlink: check for dangling peer via is_dead instead of empty list

2024-04-03T13:32:26+00:00

[ 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:
     
     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 
Signed-off-by: Jason A. Donenfeld 
Reviewed-by: Jiri Pirko 
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

wireguard: receive: annotate data-race around receiving_counter.counter

2024-03-26T22:17:35+00:00

[ 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 
Signed-off-by: Jason A. Donenfeld 
Reviewed-by: Jiri Pirko 
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

wireguard: use DEV_STATS_INC()

2023-11-19T19:48:25+00:00

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 
Signed-off-by: Eric Dumazet 
Cc: Jason A. Donenfeld 
Cc: Hangbin Liu 
Signed-off-by: Jason A. Donenfeld 
Reviewed-by: Hangbin Liu 
Signed-off-by: David S. Miller

wireguard: do not include crypto/algapi.h

2023-09-15T10:29:44+00:00

The header file crypto/algapi.h is for internal use only.  Use the
header file crypto/utils.h instead.

Acked-by: Jason A. Donenfeld 
Signed-off-by: Herbert Xu

genetlink: use attrs from struct genl_info

2023-08-15T22:00:45+00:00

Since dumps carry struct genl_info now, use the attrs pointer
from genl_info and remove the one in struct genl_dumpit_info.

Reviewed-by: Johannes Berg 
Reviewed-by: Miquel Raynal 
Reviewed-by: Jiri Pirko 
Link: https://lore.kernel.org/r/20230814214723.2924989-6-kuba@kernel.org
Signed-off-by: Jakub Kicinski

wireguard: allowedips: expand maximum node depth

2023-08-07T19:26:57+00:00

In the allowedips self-test, nodes are inserted into the tree, but it
generated an even amount of nodes, but for checking maximum node depth,
there is of course the root node, which makes the total number
necessarily odd. With two few nodes added, it never triggered the
maximum depth check like it should have. So, add 129 nodes instead of
128 nodes, and do so with a more straightforward scheme, starting with
all the bits set, and shifting over one each time. Then increase the
maximum depth to 129, and choose a better name for that variable to
make it clear that it represents depth as opposed to bits.

Cc: stable@vger.kernel.org
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld 
Link: https://lore.kernel.org/r/20230807132146.2191597-2-Jason@zx2c4.com
Signed-off-by: Jakub Kicinski

wireguard: timers: move to using timer_delete_sync

2023-07-03T08:17:52+00:00

The documentation says that del_timer_sync is obsolete, and code should
use the equivalent timer_delete_sync instead, so switch to it.

Signed-off-by: Jason A. Donenfeld 
Signed-off-by: David S. Miller

wireguard: netlink: send staged packets when setting initial private key

2023-07-03T08:17:52+00:00

Packets bound for peers can queue up prior to the device private key
being set. For example, if persistent keepalive is set, a packet is
queued up to be sent as soon as the device comes up. However, if the
private key hasn't been set yet, the handshake message never sends, and
no timer is armed to retry, since that would be pointless.

But, if a user later sets a private key, the expectation is that those
queued packets, such as a persistent keepalive, are actually sent. So
adjust the configuration logic to account for this edge case, and add a
test case to make sure this works.

Maxim noticed this with a wg-quick(8) config to the tune of:

    [Interface]
    PostUp = wg set %i private-key somefile

    [Peer]
    PublicKey = ...
    Endpoint = ...
    PersistentKeepalive = 25

Here, the private key gets set after the device comes up using a PostUp
script, triggering the bug.

Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Cc: stable@vger.kernel.org
Reported-by: Maxim Cournoyer 
Tested-by: Maxim Cournoyer 
Link: https://lore.kernel.org/wireguard/87fs7xtqrv.fsf@gmail.com/
Signed-off-by: Jason A. Donenfeld 
Signed-off-by: David S. Miller

wireguard: queueing: use saner cpu selection wrapping

2023-07-03T08:17:52+00:00

Using `% nr_cpumask_bits` is slow and complicated, and not totally
robust toward dynamic changes to CPU topologies. Rather than storing the
next CPU in the round-robin, just store the last one, and also return
that value. This simplifies the loop drastically into a much more common
pattern.

Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Cc: stable@vger.kernel.org
Reported-by: Linus Torvalds 
Tested-by: Manuel Leiner 
Signed-off-by: Jason A. Donenfeld 
Signed-off-by: David S. Miller