On 4/9/19 9:39 PM, Russell Coker wrote:
> Why is a socket that everything sends to labeled as kernel_t?
>
I see, it is happening during the system booting. /dev/log and
/run/systemd/journal/socket are both labeled kernel_t early in the boot
process. At some point they are either relabeled or recreated with
devlog_t. But without this rule the system won't boot (I have tried).
Here are a small sample of the denials I get without these rules.
type=AVC msg=audit(1554904080.089:5018): avc: denied { sendto } for
pid=7559 comm="auditd" path="/dev/log"
scontext=system_u:system_r:auditd_t:s0
tcontext=system_u:system_r:kernel_t:s0 tclass=unix_dgram_socket permissive=0
type=AVC msg=audit(1554904080.155:5138): avc: denied { sendto } for
pid=7590 comm="systemd-cgroups" path="/run/systemd/journal/socket"
scontext=system_u:system_r:systemd_cgroups_t:s0
tcontext=system_u:system_r:kernel_t:s0 tclass=unix_dgram_socket permissive=0
type=AVC msg=audit(1554904080.158:5142): avc: denied { sendto } for
pid=7591 comm="systemd-update-" path="/run/systemd/journal/socket"
scontext=system_u:system_r:initrc_t:s0
tcontext=system_u:system_r:kernel_t:s0 tclass=unix_dgram_socket permissive=0
type=AVC msg=audit(1554904467.831:181): avc: denied { sendto } for
pid=7510 comm="chronyd" path="/dev/log"
scontext=system_u:system_r:chronyd_t:s0
tcontext=system_u:system_r:kernel_t:s0 tclass=unix_dgram_socket permissive=1
type=AVC msg=audit(1554904467.842:190): avc: denied { sendto } for
pid=7498 comm="dbus-daemon" path="/dev/log"
scontext=system_u:system_r:system_dbusd_t:s0-s0:c0.c1023
tcontext=system_u:system_r:kernel_t:s0 tclass=unix_dgram_socket permissive=1
type=AVC msg=audit(1554904467.850:194): avc: denied { sendto } for
pid=7521 comm="systemd-user-se" path="/run/systemd/journal/socket"
scontext=system_u:system_r:systemd_sessions_t:s0
tcontext=system_u:system_r:kernel_t:s0 tclass=unix_dgram_socket permissive=1
> On Wednesday, 10 April 2019 11:07:29 AM AEST Sugar, David wrote:
>> On 4/9/19 9:00 PM, Russell Coker wrote:
>>
>>> Why does the kernel need such access?
>>
>>
>> I'm not sure I understand your question. Are you asking why the
>> kernel_dgram_send() access is needed by syslog? This is because many
>> domains send messages to the journal.
>>
>> I have been adding this interface as needed throughout the policy as I'm
>> seeing issues. It was suggested to move this interface use into
>> logging_send_syslog_msg as that is the same concept and most domains log
>> already.
>>
>> This patch is mostly removing uses of kernel_dgram_send and just adding
>> it one place.
>>
>>
>>>
>>> On Wednesday, 10 April 2019 1:09:59 AM AEST Sugar, David wrote:
>>>
>>>> This patch is based on comments from previous a patch to
>>>> remove the many uses of kernel_dgram_send() and incorporate
>>>> it into logging_send_syslog_msg().
>>>>
>>>>
>>>>
>>>> Signed-off-by: Dave Sugar <dsugar@xxxxxxxxxx>
>>>> ---
>>>>
>>>> policy/modules/admin/aide.te | 1 -
>>>> policy/modules/admin/usermanage.te | 5 -----
>>>> policy/modules/services/dbus.te | 3 ---
>>>> policy/modules/system/authlogin.te | 5 -----
>>>> policy/modules/system/init.if | 2 --
>>>> policy/modules/system/init.te | 3 ---
>>>> policy/modules/system/logging.if | 2 ++
>>>> policy/modules/system/logging.te | 4 ----
>>>> policy/modules/system/systemd.te | 5 -----
>>>> policy/modules/system/udev.te | 1 -
>>>> 10 files changed, 2 insertions(+), 29 deletions(-)
>>>>
>>>>
>>>>
>>>> diff --git a/policy/modules/admin/aide.te b/policy/modules/admin/aide.te
>>>> index 30deba09..f5e64a86 100644
>>>> --- a/policy/modules/admin/aide.te
>>>> +++ b/policy/modules/admin/aide.te
>>>> @@ -44,7 +44,6 @@ logging_log_filetrans(aide_t, aide_log_t, file)
>>>>
>>>> files_read_all_files(aide_t)
>>>> files_read_all_symlinks(aide_t)
>>>>
>>>>
>>>> -kernel_dgram_send(aide_t)
>>>>
>>>> kernel_read_crypto_sysctls(aide_t)
>>>>
>>>> logging_send_audit_msgs(aide_t)
>>>>
>>>> diff --git a/policy/modules/admin/usermanage.te
>>>> b/policy/modules/admin/usermanage.te
>>>>
>>> index 5753741b..4a10bf84 100644
>>>>
>>>> --- a/policy/modules/admin/usermanage.te
>>>> +++ b/policy/modules/admin/usermanage.te
>>>> @@ -366,11 +366,6 @@ userdom_read_user_tmp_files(passwd_t)
>>>>
>>>> # on user home dir
>>>> userdom_dontaudit_search_user_home_content(passwd_t)
>>>>
>>>>
>>>> -ifdef(`init_systemd',`
>>>> - # for journald /dev/log
>>>> - kernel_dgram_send(passwd_t)
>>>> -')
>>>> -
>>>>
>>>> optional_policy(`
>>>>
>>>> nscd_run(passwd_t, passwd_roles)
>>>>
>>>> ')
>>>>
>>>> diff --git a/policy/modules/services/dbus.te
>>>> b/policy/modules/services/dbus.te
>>>>
>>> index 9c085876..c05370dd 100644
>>>>
>>>> --- a/policy/modules/services/dbus.te
>>>> +++ b/policy/modules/services/dbus.te
>>>> @@ -162,9 +162,6 @@ ifdef(`init_systemd', `
>>>>
>>>> # for /run/systemd/dynamic-uid/
>>>> init_list_pids(system_dbusd_t)
>>>> init_read_runtime_symlinks(system_dbusd_t)
>>>>
>>>> -
>>>> - # for journald /dev/log
>>>> - kernel_dgram_send(system_dbusd_t)
>>>>
>>>> ')
>>>>
>>>> optional_policy(`
>>>>
>>>> diff --git a/policy/modules/system/authlogin.te
>>>> b/policy/modules/system/authlogin.te
>>>>
>>> index 28f74bac..2cf86952 100644
>>>>
>>>> --- a/policy/modules/system/authlogin.te
>>>> +++ b/policy/modules/system/authlogin.te
>>>> @@ -144,11 +144,6 @@ ifdef(`distro_ubuntu',`
>>>>
>>>> ')
>>>>
>>>> ')
>>>>
>>>>
>>>> -ifdef(`init_systemd',`
>>>> - # for journald /dev/log
>>>> - kernel_dgram_send(chkpwd_t)
>>>> -')
>>>> -
>>>>
>>>> optional_policy(`
>>>>
>>>> # apache leaks file descriptors
>>>> apache_dontaudit_rw_tcp_sockets(chkpwd_t)
>>>>
>>>> diff --git a/policy/modules/system/init.if
>>>> b/policy/modules/system/init.if
>>>> index fef2c88e..00bd4991 100644
>>>> --- a/policy/modules/system/init.if
>>>> +++ b/policy/modules/system/init.if
>>>> @@ -306,8 +306,6 @@ interface(`init_daemon_domain',`
>>>>
>>>>
>>>>
>>>> ifdef(`init_systemd',`
>>>>
>>>> init_domain($1, $2)
>>>>
>>>> - # this may be because of late labelling
>>>> - kernel_dgram_send($1)
>>>>
>>>>
>>>>
>>>> allow $1 init_t:unix_dgram_socket sendto;
>>>>
>>>> ')
>>>>
>>>> diff --git a/policy/modules/system/init.te
>>>> b/policy/modules/system/init.te
>>>> index a12d151b..3e8eb2da 100644
>>>> --- a/policy/modules/system/init.te
>>>> +++ b/policy/modules/system/init.te
>>>> @@ -272,7 +272,6 @@ ifdef(`init_systemd',`
>>>>
>>>>
>>>>
>>>> kernel_dyntrans_to(init_t)
>>>> kernel_read_network_state(init_t)
>>>>
>>>> - kernel_dgram_send(init_t)
>>>>
>>>> kernel_stream_connect(init_t)
>>>> kernel_getattr_proc(init_t)
>>>> kernel_read_fs_sysctls(init_t)
>>>>
>>>> @@ -969,8 +968,6 @@ ifdef(`init_systemd',`
>>>>
>>>> allow initrc_t systemdunit:service reload;
>>>> allow initrc_t init_script_file_type:service { stop start status
>>>> reload
>>>>
>>>> };
>>>>
>>>
>>>>
>>>> - kernel_dgram_send(initrc_t)
>>>> -
>>>>
>>>> # run systemd misc initializations
>>>> # in the initrc_t domain, as would be
>>>> # done in traditional sysvinit/upstart.
>>>>
>>>> diff --git a/policy/modules/system/logging.if
>>>> b/policy/modules/system/logging.if
>>>>
>>> index 7b7644f7..1f696b7f 100644
>>>>
>>>> --- a/policy/modules/system/logging.if
>>>> +++ b/policy/modules/system/logging.if
>>>> @@ -642,6 +642,8 @@ interface(`logging_send_syslog_msg',`
>>>>
>>>> ifdef(`init_systemd',`
>>>>
>>>> # Allow systemd-journald to check whether the process died
>>>> allow syslogd_t $1:process signull;
>>>>
>>>> +
>>>> + kernel_dgram_send($1)
>>>>
>>>> ')
>>>>
>>>> ')
>>>>
>>>>
>>>> diff --git a/policy/modules/system/logging.te
>>>> b/policy/modules/system/logging.te
>>>>
>>> index 0c5be1cd..02f268ea 100644
>>>>
>>>> --- a/policy/modules/system/logging.te
>>>> +++ b/policy/modules/system/logging.te
>>>> @@ -271,10 +271,6 @@ miscfiles_read_localization(audisp_t)
>>>>
>>>>
>>>> sysnet_dns_name_resolve(audisp_t)
>>>>
>>>>
>>>> -ifdef(`init_systemd',`
>>>> - kernel_dgram_send(audisp_t)
>>>> -')
>>>> -
>>>>
>>>> optional_policy(`
>>>>
>>>> dbus_system_bus_client(audisp_t)
>>>>
>>>> ')
>>>>
>>>> diff --git a/policy/modules/system/systemd.te
>>>> b/policy/modules/system/systemd.te
>>>>
>>> index f6455f6f..cf9241c0 100644
>>>>
>>>> --- a/policy/modules/system/systemd.te
>>>> +++ b/policy/modules/system/systemd.te
>>>> @@ -266,7 +266,6 @@
>>>> systemd_log_parse_environment(systemd_gpt_generator_t)
>>>>
>>>> allow systemd_cgroups_t self:capability net_admin;
>>>>
>>>> kernel_domtrans_to(systemd_cgroups_t, systemd_cgroups_exec_t)
>>>>
>>>> -kernel_dgram_send(systemd_cgroups_t)
>>>>
>>>> # for /proc/cmdline
>>>> kernel_read_system_state(systemd_cgroups_t)
>>>>
>>>>
>>>> @@ -642,7 +641,6 @@ manage_dirs_pattern(systemd_networkd_t,
>>>> systemd_networkd_var_run_t, systemd_netw
>>>> manage_files_pattern(systemd_networkd_t, systemd_networkd_var_run_t,
>>>> systemd_networkd_var_run_t) manage_lnk_files_pattern(systemd_networkd_t,
>>>> systemd_networkd_var_run_t, systemd_networkd_var_run_t)
>>>> -kernel_dgram_send(systemd_networkd_t)
>>>>
>>>> kernel_read_system_state(systemd_networkd_t)
>>>> kernel_read_kernel_sysctls(systemd_networkd_t)
>>>> kernel_read_network_state(systemd_networkd_t)
>>>>
>>>> @@ -667,8 +665,6 @@ auth_use_nsswitch(systemd_networkd_t)
>>>>
>>>> init_dgram_send(systemd_networkd_t)
>>>> init_read_state(systemd_networkd_t)
>>>>
>>>>
>>>> -logging_send_syslog_msg(systemd_networkd_t)
>>>> -
>>>>
>>>> miscfiles_read_localization(systemd_networkd_t)
>>>>
>>>> sysnet_read_config(systemd_networkd_t)
>>>>
>>>> @@ -945,7 +941,6 @@ init_pid_filetrans(systemd_resolved_t,
>>>> systemd_resolved_var_run_t, dir)
>>>>
>>>
>>>
>>>> dev_read_sysfs(systemd_resolved_t)
>>>>
>>>>
>>>> -kernel_dgram_send(systemd_resolved_t)
>>>>
>>>> kernel_read_crypto_sysctls(systemd_resolved_t)
>>>> kernel_read_kernel_sysctls(systemd_resolved_t)
>>>> kernel_read_net_sysctls(systemd_resolved_t)
>>>>
>>>> diff --git a/policy/modules/system/udev.te
>>>> b/policy/modules/system/udev.te
>>>> index ff564280..f00de30d 100644
>>>> --- a/policy/modules/system/udev.te
>>>> +++ b/policy/modules/system/udev.te
>>>> @@ -99,7 +99,6 @@ kernel_read_modprobe_sysctls(udev_t)
>>>>
>>>> kernel_read_kernel_sysctls(udev_t)
>>>> kernel_rw_hotplug_sysctls(udev_t)
>>>> kernel_rw_unix_dgram_sockets(udev_t)
>>>>
>>>> -kernel_dgram_send(udev_t)
>>>>
>>>> kernel_signal(udev_t)
>>>> kernel_search_debugfs(udev_t)
>>>> kernel_search_key(udev_t)
>>>>
>>>> --
>>>> 2.20.1
>>>>
>>>>
>>>>
>>>
>
>
