Re: [PATCH] LSM: add NULL check for kcalloc()

From: Austin Kim
Date: Wed Jul 14 2021 - 17:45:07 EST


2021년 7월 15일 (목) 오전 4:12, James Morris <jmorris@xxxxxxxxx>님이 작성:
>
> On Tue, 13 Jul 2021, Austin Kim wrote:
>
> > From: Austin Kim <austin.kim@xxxxxxx>
> >
> > kcalloc() may return NULL when memory allocation fails.
> > So it is necessary to add NULL check after the call to kcalloc() is made.
> >
> > Signed-off-by: Austin Kim <austin.kim@xxxxxxx>
> > ---
> > security/security.c | 2 ++
> > 1 file changed, 2 insertions(+)
> >
> > diff --git a/security/security.c b/security/security.c
> > index 09533cbb7221..f885c9e9bc35 100644
> > --- a/security/security.c
> > +++ b/security/security.c
> > @@ -321,6 +321,8 @@ static void __init ordered_lsm_init(void)
> >
> > ordered_lsms = kcalloc(LSM_COUNT + 1, sizeof(*ordered_lsms),
> > GFP_KERNEL);
> > + if (ordered_lsms)
> > + return;
>
> Your logic is reversed here.

I feel very sorry for my terrible mistake.
'if (ordered_lsms)' should have been 'if (!ordered_lsms)'.

Let me resend patch(v2) soon.

Thanks,
Austin Kim

>
> Should this also be a kernel panic?
>
> >
> > if (chosen_lsm_order) {
> > if (chosen_major_lsm) {
> > --
> > 2.20.1
> >
>
> --
> James Morris
> <jmorris@xxxxxxxxx>
>