Fix capabilities installed via systemd service (fixes netlink/IO priorities)

CapabilityBoundingSet that contained in systemd unit before is about
allowing to set some capabilities, not about granting them.

To grant them you need to use AmbientCapabilities.

And if you do not use 'clickhouse install' then:
- IO priorities was unavailable (since they requires CAP_SYS_NICE)
- For taskstats the procfs was used instead of netlink

Not a big deal, but still.

Here how it had been tested:

    $ systemd-run -p CapabilityBoundingSet=CAP_NET_ADMIN --shell
    root:/etc (master)# capsh --print
    Current: cap_net_admin=ep
    Bounding set =cap_net_admin
    Ambient set =

    $ systemd-run -p User=azat -p CapabilityBoundingSet=CAP_NET_ADMIN --shell
    azat:/etc$ capsh --print
    Current: =
    Bounding set =cap_net_admin
    Ambient set =

    $ systemd-run -p User=azat -p AmbientCapabilities=CAP_NET_ADMIN -p CapabilityBoundingSet=CAP_NET_ADMIN --shell
    azat:/etc$ capsh --print
    Current: cap_net_admin=eip
    Bounding set =cap_net_admin
    Ambient set =cap_net_admin

Note, if you are running it under root (without changing user) you don't
need to specify AmbientCapabilities additionally, because root has all
capabilities by default and they had been inherited.

Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
This commit is contained in:
Azat Khuzhin 2023-07-20 12:38:57 +02:00
parent 1c2fea4980
commit 1fe8076b94

View File

@ -29,6 +29,7 @@ EnvironmentFile=-/etc/default/clickhouse
LimitCORE=infinity
LimitNOFILE=500000
CapabilityBoundingSet=CAP_NET_ADMIN CAP_IPC_LOCK CAP_SYS_NICE CAP_NET_BIND_SERVICE
AmbientCapabilities=CAP_NET_ADMIN CAP_IPC_LOCK CAP_SYS_NICE CAP_NET_BIND_SERVICE
[Install]
# ClickHouse should not start from the rescue shell (rescue.target).