2020-01-23 12:41:00

by Sugar, David

Subject: [PATCH v3] Allow systemd to getattr all files

Systemd has ConditionPath.*, ConditionFile.* and ConditionDir* which
are used to check various path/file/directory to control starting a
service. But this requires getattr permissions on the types.
Example denials that fit the problem.

The first example is from lvm where accessing config file.

type=AVC msg=audit(1575427946.229:1624): avc: denied { getattr } for
pid=1 comm="systemd" path="/etc/lvm/lvm.conf" dev="dm-0" ino=51799
scontext=system_u:system_r:init_t:s0
tcontext=system_u:object_r:lvm_etc_t:s0 tclass=file permissive=0

This second example is from chronyd, but it is happening becuase I added
the conditional in a drop-in file.

type=AVC msg=audit(1575427959.882:1901): avc: denied { getattr } for
pid=1 comm="systemd" path="/etc/chrony.conf" dev="dm-0" ino=53824
scontext=system_u:system_r:init_t:s0
tcontext=system_u:object_r:chronyd_conf_t:s0 tclass=file permissive=1

v3 - rework to not use interface and allow getattr for all files

Signed-off-by: Dave Sugar <[email protected]>
---
policy/modules/system/init.te | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/policy/modules/system/init.te b/policy/modules/system/init.te
index 281d4fd2..c772ff40 100644
--- a/policy/modules/system/init.te
+++ b/policy/modules/system/init.te
@@ -335,6 +335,11 @@ ifdef(`init_systemd',`
domain_subj_id_change_exemption(init_t)
domain_role_change_exemption(init_t)

+ files_getattr_all_dirs(init_t)
+ files_getattr_all_files(init_t)
+ files_getattr_all_pipes(init_t)
+ files_getattr_all_sockets(init_t)
+ files_read_all_symlinks(init_t)
files_read_all_pids(init_t)
files_list_usr(init_t)
files_list_var(init_t)
--
2.24.1

2020-01-30 14:41:05

by Sugar, David

Subject: Re: [PATCH v3] Allow systemd to getattr all files

Can this get merged? I have not seen any comments.
Would you prefer if I use a github pull request?

On 1/23/20 7:40 AM, Sugar, David wrote:
> Systemd has ConditionPath.*, ConditionFile.* and ConditionDir* which
> are used to check various path/file/directory to control starting a
> service. But this requires getattr permissions on the types.
> Example denials that fit the problem.
>
> The first example is from lvm where accessing config file.
>
> type=AVC msg=audit(1575427946.229:1624): avc: denied { getattr } for
> pid=1 comm="systemd" path="/etc/lvm/lvm.conf" dev="dm-0" ino=51799
> scontext=system_u:system_r:init_t:s0
> tcontext=system_u:object_r:lvm_etc_t:s0 tclass=file permissive=0
>
> This second example is from chronyd, but it is happening becuase I added
> the conditional in a drop-in file.
>
> type=AVC msg=audit(1575427959.882:1901): avc: denied { getattr } for
> pid=1 comm="systemd" path="/etc/chrony.conf" dev="dm-0" ino=53824
> scontext=system_u:system_r:init_t:s0
> tcontext=system_u:object_r:chronyd_conf_t:s0 tclass=file permissive=1
>
> v3 - rework to not use interface and allow getattr for all files
>
> Signed-off-by: Dave Sugar <[email protected]>
> ---
> policy/modules/system/init.te | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/policy/modules/system/init.te b/policy/modules/system/init.te
> index 281d4fd2..c772ff40 100644
> --- a/policy/modules/system/init.te
> +++ b/policy/modules/system/init.te
> @@ -335,6 +335,11 @@ ifdef(`init_systemd',`
> domain_subj_id_change_exemption(init_t)
> domain_role_change_exemption(init_t)
>
> + files_getattr_all_dirs(init_t)
> + files_getattr_all_files(init_t)
> + files_getattr_all_pipes(init_t)
> + files_getattr_all_sockets(init_t)
> + files_read_all_symlinks(init_t)
> files_read_all_pids(init_t)
> files_list_usr(init_t)
> files_list_var(init_t)
>

2020-02-08 14:50:11

by Chris PeBenito

Subject: Re: [PATCH v3] Allow systemd to getattr all files

On 1/23/20 7:40 AM, Sugar, David wrote:
> Systemd has ConditionPath.*, ConditionFile.* and ConditionDir* which
> are used to check various path/file/directory to control starting a
> service. But this requires getattr permissions on the types.
> Example denials that fit the problem.
>
> The first example is from lvm where accessing config file.
>
> type=AVC msg=audit(1575427946.229:1624): avc: denied { getattr } for
> pid=1 comm="systemd" path="/etc/lvm/lvm.conf" dev="dm-0" ino=51799
> scontext=system_u:system_r:init_t:s0
> tcontext=system_u:object_r:lvm_etc_t:s0 tclass=file permissive=0
>
> This second example is from chronyd, but it is happening becuase I added
> the conditional in a drop-in file.
>
> type=AVC msg=audit(1575427959.882:1901): avc: denied { getattr } for
> pid=1 comm="systemd" path="/etc/chrony.conf" dev="dm-0" ino=53824
> scontext=system_u:system_r:init_t:s0
> tcontext=system_u:object_r:chronyd_conf_t:s0 tclass=file permissive=1
>
> v3 - rework to not use interface and allow getattr for all files
>
> Signed-off-by: Dave Sugar <[email protected]>
> ---
> policy/modules/system/init.te | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/policy/modules/system/init.te b/policy/modules/system/init.te
> index 281d4fd2..c772ff40 100644
> --- a/policy/modules/system/init.te
> +++ b/policy/modules/system/init.te
> @@ -335,6 +335,11 @@ ifdef(`init_systemd',`
> domain_subj_id_change_exemption(init_t)
> domain_role_change_exemption(init_t)
>
> + files_getattr_all_dirs(init_t)
> + files_getattr_all_files(init_t)
> + files_getattr_all_pipes(init_t)
> + files_getattr_all_sockets(init_t)
> + files_read_all_symlinks(init_t)
> files_read_all_pids(init_t)
> files_list_usr(init_t)
> files_list_var(init_t)

Sorry for the delay. Merged.

--
Chris PeBenito