linux.git/drivers/net/wireguard, branch v6.9-rc2

wireguard: netlink: access device through ctx instead of peer

2024-03-19T10:22:50+00:00

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

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

2024-03-19T10:22:50+00:00

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

wireguard: device: remove generic .ndo_get_stats64

2024-03-19T10:22:49+00:00

Commit 3e2f544dd8a33 ("net: get stats64 if device if driver is
configured") moved the callback to dev_get_tstats64() to net core, so,
unless the driver is doing some custom stats collection, it does not
need to set .ndo_get_stats64.

Since this driver is now relying in NETDEV_PCPU_STAT_TSTATS, then, it
doesn't need to set the dev_get_tstats64() generic .ndo_get_stats64
function pointer.

Signed-off-by: Breno Leitao 
Reviewed-by: Simon Horman 
Signed-off-by: Jason A. Donenfeld 
Reviewed-by: Jiri Pirko 
Signed-off-by: Paolo Abeni

wireguard: device: leverage core stats allocator

2024-03-19T10:22:49+00:00

With commit 34d21de99cea9 ("net: Move {l,t,d}stats allocation to core
and convert veth & vrf"), stats allocation could be done on net core
instead of in this driver.

With this new approach, the driver doesn't have to bother with error
handling (allocation failure checking, making sure free happens in the
right spot, etc). This is core responsibility now.

Remove the allocation in this driver and leverage the network core
allocation instead.

Signed-off-by: Breno Leitao 
Reviewed-by: Simon Horman 
Signed-off-by: Jason A. Donenfeld 
Reviewed-by: Jiri Pirko 
Signed-off-by: Paolo Abeni

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

2024-03-19T10:22:49+00:00

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

net: adopt skb_network_offset() and similar helpers

2024-03-04T08:47:06+00:00

This is a cleanup patch, making code a bit more concise.

1) Use skb_network_offset(skb) in place of
       (skb_network_header(skb) - skb->data)

2) Use -skb_network_offset(skb) in place of
       (skb->data - skb_network_header(skb))

3) Use skb_transport_offset(skb) in place of
       (skb_transport_header(skb) - skb->data)

4) Use skb_inner_transport_offset(skb) in place of
       (skb_inner_transport_header(skb) - skb->data)

Signed-off-by: Eric Dumazet 
Acked-by: Edward Cree  # for sfc
Signed-off-by: David S. Miller

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