linux-kernel - Re: [RFC PATCH 4/4] riscv: Introduce set_compat

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <ZYVIpSVzJYGMYPD2@LeoBras>
Date: Fri, 22 Dec 2023 05:28:21 -0300
From: Leonardo Bras <leobras@...hat.com>
To: Guo Ren <guoren@...nel.org>
Cc: Leonardo Bras <leobras@...hat.com>,
	Paul Walmsley <paul.walmsley@...ive.com>,
	Palmer Dabbelt <palmer@...belt.com>,
	Albert Ou <aou@...s.berkeley.edu>,
	Eric Biederman <ebiederm@...ssion.com>,
	Kees Cook <keescook@...omium.org>,
	Oleg Nesterov <oleg@...hat.com>,
	Conor Dooley <conor.dooley@...rochip.com>,
	Andy Chiu <andy.chiu@...ive.com>,
	Greg Ungerer <gerg@...nel.org>,
	Vincent Chen <vincent.chen@...ive.com>,
	Xiao Wang <xiao.w.wang@...el.com>,
	Charlie Jenkins <charlie@...osinc.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Alexandre Ghiti <alexghiti@...osinc.com>,
	Kemeng Shi <shikemeng@...weicloud.com>,
	David Hildenbrand <david@...hat.com>,
	"Matthew Wilcox (Oracle)" <willy@...radead.org>,
	Qinglin Pan <panqinglin2020@...as.ac.cn>,
	Greentime Hu <greentime.hu@...ive.com>,
	Björn Töpel <bjorn@...osinc.com>,
	Clément Léger <cleger@...osinc.com>,
	linux-riscv@...ts.infradead.org,
	linux-kernel@...r.kernel.org,
	linux-mm@...ck.org
Subject: Re: [RFC PATCH 4/4] riscv: Introduce set_compat_task() in asm/compat.h

On Fri, Dec 22, 2023 at 04:11:10PM +0800, Guo Ren wrote:
> On Fri, Dec 22, 2023 at 3:47 PM Leonardo Bras <leobras@...hat.com> wrote:
> >
> > In order to have all task compat bit access directly in compat.h, introduce
> > set_compat_task() to set/reset those when needed.
> >
> > Also, since it's only used on an if/else scenario, simplify the macro using
> > it.
> >
> > Signed-off-by: Leonardo Bras <leobras@...hat.com>
> > ---
> >  arch/riscv/include/asm/compat.h | 8 ++++++++
> >  arch/riscv/include/asm/elf.h    | 5 +----
> >  2 files changed, 9 insertions(+), 4 deletions(-)
> >
> > diff --git a/arch/riscv/include/asm/compat.h b/arch/riscv/include/asm/compat.h
> > index da4b28cd01a95..aa103530a5c83 100644
> > --- a/arch/riscv/include/asm/compat.h
> > +++ b/arch/riscv/include/asm/compat.h
> > @@ -28,6 +28,14 @@ static inline int is_compat_thread(struct thread_info *thread)
> >         return test_ti_thread_flag(thread, TIF_32BIT);
> >  }
> >
> > +static inline void set_compat_task(bool is_compat)
> > +{
> > +       if (is_compat)
> > +               set_thread_flag(TIF_32BIT);
> > +       else
> > +               clear_thread_flag(TIF_32BIT);
> > +}
> > +
> >  struct compat_user_regs_struct {
> >         compat_ulong_t pc;
> >         compat_ulong_t ra;
> > diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h
> > index 2e88257cafaea..c7aea7886d22a 100644
> > --- a/arch/riscv/include/asm/elf.h
> > +++ b/arch/riscv/include/asm/elf.h
> > @@ -135,10 +135,7 @@ do {                                                       \
> >  #ifdef CONFIG_COMPAT
> >
> >  #define SET_PERSONALITY(ex)                                    \
> > -do {    if ((ex).e_ident[EI_CLASS] == ELFCLASS32)              \
> > -               set_thread_flag(TIF_32BIT);                     \
> > -       else                                                    \
> > -               clear_thread_flag(TIF_32BIT);                   \
> > +do {   set_compat_task((ex).e_ident[EI_CLASS] == ELFCLASS32);  \
> >         if (personality(current->personality) != PER_LINUX32)   \
> >                 set_personality(PER_LINUX |                     \
> >                         (current->personality & (~PER_MASK)));  \
> > --
> > 2.43.0
> >
> LGTM
> 
> Reviewed-by: Guo Ren <guoren@...nel.org>

Thanks!
Leo

> 
> -- 
> Best Regards
>  Guo Ren
>