Re: [PATCH] security: min_addr: use max() to improve code

[Qianfeng Rong]

在 2025/8/15 10:17, Paul Moore 写道:
> On Aug 14, 2025 Qianfeng Rong <rongqianfeng@xxxxxxxx> wrote:
> > Use max() to reduce the code in update_mmap_min_addr() and improve its
> > readability.
> >
> > Signed-off-by: Qianfeng Rong <rongqianfeng@xxxxxxxx>
> > ---
> >   security/min_addr.c | 5 +----
> >   1 file changed, 1 insertion(+), 4 deletions(-)
> >
> > diff --git a/security/min_addr.c b/security/min_addr.c
> > index df1bc643d886..50035bc9281c 100644
> > --- a/security/min_addr.c
> > +++ b/security/min_addr.c
> > @@ -16,10 +16,7 @@ unsigned long dac_mmap_min_addr = CONFIG_DEFAULT_MMAP_MIN_ADDR;
> >   static void update_mmap_min_addr(void)
> >   {
> >   #ifdef CONFIG_LSM_MMAP_MIN_ADDR
> > -	if (dac_mmap_min_addr > CONFIG_LSM_MMAP_MIN_ADDR)
> > -		mmap_min_addr = dac_mmap_min_addr;
> > -	else
> > -		mmap_min_addr = CONFIG_LSM_MMAP_MIN_ADDR;
> > +	mmap_min_addr = max(dac_mmap_min_addr, CONFIG_LSM_MMAP_MIN_ADDR);
> It seems like the umax() macro would be a better choice here, yes?


You are right, using umax() here makes the semantics clearer.

> It might also be a good idea to explicitly include the
> include/linux/minmax.h header in this file.


ok, Will do in the next version.

> >   #else
> >   	mmap_min_addr = dac_mmap_min_addr;
> >   #endif
> > --
> > 2.34.1
> --
> paul-moore.com
Best regards,
Qianfeng