On 21/02/2021 09:50, Masahiro Yamada wrote: > On Tue, Feb 16, 2021 at 4:03 AM Ondrej Mosnacek <omosnace@xxxxxxxxxx> wrote: >> >> On Mon, Feb 15, 2021 at 7:17 PM Mickaël Salaün <mic@xxxxxxxxxxx> wrote: >>> From: Mickaël Salaün <mic@xxxxxxxxxxxxxxxxxxx> >>> >>> Thanks to the previous commit, this gives the opportunity to users, when >>> running make oldconfig, to update the list of enabled LSMs at boot time >>> if an LSM has just been enabled or disabled in the build. Moreover, >>> this list only makes sense if at least one LSM is enabled. >>> >>> Cc: Casey Schaufler <casey@xxxxxxxxxxxxxxxx> >>> Cc: James Morris <jmorris@xxxxxxxxx> >>> Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx> >>> Cc: Serge E. Hallyn <serge@xxxxxxxxxx> >>> Signed-off-by: Mickaël Salaün <mic@xxxxxxxxxxxxxxxxxxx> >>> Link: https://lore.kernel.org/r/20210215181511.2840674-4-mic@xxxxxxxxxxx >>> --- >>> >>> Changes since v1: >>> * Add CONFIG_SECURITY as a dependency of CONFIG_LSM. This prevent an >>> error when building without any LSMs. >>> --- >>> security/Kconfig | 4 ++++ >>> 1 file changed, 4 insertions(+) >>> >>> diff --git a/security/Kconfig b/security/Kconfig >>> index 7561f6f99f1d..addcc1c04701 100644 >>> --- a/security/Kconfig >>> +++ b/security/Kconfig >>> @@ -277,6 +277,10 @@ endchoice >>> >>> config LSM >>> string "Ordered list of enabled LSMs" >>> + depends on SECURITY || SECURITY_LOCKDOWN_LSM || SECURITY_YAMA || \ >>> + SECURITY_LOADPIN || SECURITY_SAFESETID || INTEGRITY || \ >>> + SECURITY_SELINUX || SECURITY_SMACK || SECURITY_TOMOYO || \ >>> + SECURITY_APPARMOR || BPF_LSM >> >> This looks really awkward, since all of these already depend on >> SECURITY (if not, it's a bug)... I guarantee you that after some time >> someone will come, see that the weird boolean expression is equivalent >> to just SECURITY, and simplify it. > > > Currently, LSM does not depend on SECURITY. > So you can always define LSM irrespective of SECURITY, > which seems a bug. > > So, I agree with adding 'depends on SECURITY'. > > What he is trying to achieve in this series > seems wrong, of course. This may be wrong in the general case, but not for CONFIG_LSM. > > >> I assume the new mechanism wouldn't work as intended if there is just >> SECURITY? If not, then maybe you should rather specify this value >> dependency via some new field rather than abusing "depends on" (say, >> "value depends on"?). The fact that a seemingly innocent change to the >> config definition breaks your mechanism suggests that the design is >> flawed. Masahiro, what do you think about this suggested "value depends on"? >> >> I do think this would be a useful feature, but IMHO shouldn't be >> implemented like this. >> >>> default "lockdown,yama,loadpin,safesetid,integrity,smack,selinux,tomoyo,apparmor,bpf" if DEFAULT_SECURITY_SMACK >>> default "lockdown,yama,loadpin,safesetid,integrity,apparmor,selinux,smack,tomoyo,bpf" if DEFAULT_SECURITY_APPARMOR >>> default "lockdown,yama,loadpin,safesetid,integrity,tomoyo,bpf" if DEFAULT_SECURITY_TOMOYO >>> -- >>> 2.30.0 >>> >> >> -- >> Ondrej Mosnacek >> Software Engineer, Linux Security - SELinux kernel >> Red Hat, Inc. >> > >
