Re: [PATCH] capability: erase checker warnings about struct __user_cap_data_struct

From: Paul Moore
Date: Tue Jun 06 2023 - 17:07:58 EST


On Tue, Jun 6, 2023 at 1:50 PM Serge E. Hallyn <serge@xxxxxxxxxx> wrote:
> On Tue, Jun 06, 2023 at 12:45:00PM -0400, Paul Moore wrote:
> > On Mon, Jun 5, 2023 at 11:29 PM Serge E. Hallyn <serge@xxxxxxxxxx> wrote:
> > > On Fri, Jun 02, 2023 at 01:45:27PM +0800, GONG, Ruiqi wrote:
> > > > Currently Sparse warns the following when compiling kernel/capability.c:
> > > >
> > > > kernel/capability.c:191:35: warning: incorrect type in argument 2 (different address spaces)
> > > > kernel/capability.c:191:35: expected void const *from
> > > > kernel/capability.c:191:35: got struct __user_cap_data_struct [noderef] __user *
> > > > kernel/capability.c:168:14: warning: dereference of noderef expression
> > > > ...... (multiple noderef warnings on different locations)
> > > > kernel/capability.c:244:29: warning: incorrect type in argument 1 (different address spaces)
> > > > kernel/capability.c:244:29: expected void *to
> > > > kernel/capability.c:244:29: got struct __user_cap_data_struct [noderef] __user ( * )[2]
> > > > kernel/capability.c:247:42: warning: dereference of noderef expression
> > > > ...... (multiple noderef warnings on different locations)
> > > >
> > > > It seems that defining `struct __user_cap_data_struct` together with
> > > > `cap_user_data_t` make Sparse believe that the struct is `noderef` as
> > > > well. Separate their definitions to clarify their respective attributes.
> > > >
> > > > Signed-off-by: GONG, Ruiqi <gongruiqi@xxxxxxxxxxxxxxx>
> > >
> > > Seems ok.
> > >
> > > There's still so much noise in the make C=2 output even just for
> > > kernel/capability.c that I'm not sure it's worth it, but no
> > > objection.
> > >
> > > Acked-by: Serge Hallyn <serge@xxxxxxxxxx>
> >
> > I'm guessing you would prefer if I pulled this via the LSM tree Serge?
>
> Yes, please.

Done, it's merged into lsm/next.

> > FWIW, if that is ever the case for future patches, just add a note
> > when you ACK something and I'll pick it up.
>
> Thanks, will do.
>
> If it starts happening more than once or twice a month, then I'll get my tree
> into shape and start cueing up patches...

No problem, as long as the patches are fairly trivial I don't mind.

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