WARNING in apparmor_secid_to_secctx

[Tetsuo Handa]

On 2019/01/30 23:45, Dmitry Vyukov wrote:
>> Dmitry, is it possible to update configs for linux-next.git , for
>> we want to test a big change in LSM which will go to Linux 5.1 ?
>>
>> TOMOYO security module (CONFIG_SECURITY_TOMOYO=y) can now coexist with
>> SELinux/Smack/AppArmor security modules, and SafeSetID security module
>> (CONFIG_SECURITY_SAFESETID=y) was added. Testing with these modules also
>> enabled might find something...
> 
> Hi,
> 
> syzbot configs/cmdline args are stored here:
> https://github.com/google/syzkaller/tree/master/dashboard/config
> 
> I've tried to update to the latest kernel, the diff is below.
> Few questions:
> 1. How are modules enabled now?
> We pass security=selinux of security=smack on command line. What do we
> need to pass now to enable several modules at the same time?

Removing security= parameter from kernel boot command line will do it.

  security/apparmor/lsm.c:        .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
  security/selinux/hooks.c:       .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
  security/smack/smack_lsm.c:     .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
  security/tomoyo/tomoyo.c:       .flags = LSM_FLAG_LEGACY_MAJOR,
  security/security.c:                    if ((major->flags & LSM_FLAG_LEGACY_MAJOR) &&

But this means that, if same kernel config/cmdline are used between
linux-next.git and linux.git (etc.), syzbot will need to choose from

 (a) stop sharing kernel cmdline between linux-next.git and linux.git (etc.)

or

 (b) stop sharing kernel config between SELinux, Smack and AppArmor

or

 (c) start testing after the LSM changes went to linux.git as Linux 5.1-rc1

. Is (a) or (b) possible? If this is a too much change, (c) will be OK.