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Message-ID: <0a4ebcd2-7772-4832-885d-221e0c6f6c04@schaufler-ca.com>
Date: Mon, 15 Apr 2024 13:54:28 -0700
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Subject: Re: [kpsingh:static_calls] [security] 9e15595ed0:
 Kernel_panic-not_syncing:lsm_static_call_init-Ran_out_of_static_slots
To: KP Singh <kpsingh@kernel.org>, Paul Moore <paul@paul-moore.com>
Cc: Andrii Nakryiko <andrii@kernel.org>, Kees Cook <keescook@chromium.org>,
 Song Liu <song@kernel.org>, Tetsuo Handa
 <penguin-kernel@i-love.sakura.ne.jp>,
 kernel test robot <oliver.sang@intel.com>, linux-kernel@vger.kernel.org,
 linux-security-module@vger.kernel.org, lkp@intel.com,
 oe-lkp@lists.linux.dev, Casey Schaufler <casey@schaufler-ca.com>
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From: Casey Schaufler <casey@schaufler-ca.com>
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On 4/15/2024 1:42 PM, KP Singh wrote:
>
>> On 15 Apr 2024, at 17:47, KP Singh <kpsingh@kernel.org> wrote:
>>
>>
> [...]
>
>>> <penguin-kernel@i-love.sakura.ne.jp> wrote:
>>>> On 2024/04/15 17:26, KP Singh wrote:
>>>>> This seems like an odd config which does not enable STATIC_CALL, I am going to
>>>>> make CONFIG_SECURITY depend on CONFIG_STATIC_CALL and make the dependency explicit.
>>>> If CONFIG_SECURITY depends on CONFIG_STATIC_CALL, architectures which do not
>>>> support CONFIG_STATIC_CALL can no longer use LSM ? That sounds a bad dependency.
>>> Agreed.  If the arch doesn't support static calls we need a fallback
>>> solution for the LSM that is no worse than what we have now, and
>>> preferably would still solve the issue of the BPF hooks active even
>>> where this is no BPF program attached.
>> Actually I take it back, when CONFIG_STATIC_CALL is not available, the implementation falls back to an indirect call. This crash is unrelated, I will debug further and post back.
>  Apparently, when I smoke tested, I had CONFIG_IMA disabled so did not hit the bug. Well, now IMA is an LSM, so the following fixes it:

You'll want CONFIG_EVM as well, I bet.