Re: [PATCH v1] LSM: Enable multiple calls to security_add_hooks() for the same LSM

[Tetsuo Handa]

Casey Schaufler wrote:
> On 4/29/2017 12:02 PM, Mickael Salaun wrote:
> > Check if the registering LSM already registered hooks just before. This
> > enable to split hook declarations into multiple files without
> > registering multiple time the same LSM name, starting from commit
> > d69dece5f5b6 ("LSM: Add /sys/kernel/security/lsm").
> 
> What's special about the previous registration? Keep it
> simple and check it the name is already anywhere on the
> list and only add it if it's not already there. I don't
> see advantage to:
> 
> 	% cat /sys/kernel/security/lsm
> 	capability,yama,spiffy,selinux,spiffy
> 
> over
> 	% cat /sys/kernel/security/lsm
> 	capability,yama,spiffy,selinux
> 

-	if (lsm_append(lsm, &lsm_names) < 0)
+	if (lsm && lsm_append(lsm, &lsm_names) < 0)

in security_add_hooks()?