[PATCH v5 11/21] powerpc: Define and use __get_user_instr{, inatomic}()

[Jordan Niethe]

On Tue, Apr 7, 2020 at 8:48 PM Balamuruhan S <bala24 at linux.ibm.com> wrote:
>
> On Mon, 2020-04-06 at 18:09 +1000, Jordan Niethe wrote:
> > Define specific __get_user_instr() and __get_user_instr_inatomic()
> > macros for reading instructions from user space.
> >
> > Signed-off-by: Jordan Niethe <jniethe5 at gmail.com>
> > ---
> >  arch/powerpc/include/asm/uaccess.h  | 5 +++++
> >  arch/powerpc/kernel/align.c         | 2 +-
> >  arch/powerpc/kernel/hw_breakpoint.c | 2 +-
> >  arch/powerpc/kernel/vecemu.c        | 2 +-
> >  4 files changed, 8 insertions(+), 3 deletions(-)
> >
> > diff --git a/arch/powerpc/include/asm/uaccess.h
> > b/arch/powerpc/include/asm/uaccess.h
> > index 2f500debae21..c0a35e4586a5 100644
> > --- a/arch/powerpc/include/asm/uaccess.h
> > +++ b/arch/powerpc/include/asm/uaccess.h
> > @@ -105,6 +105,11 @@ static inline int __access_ok(unsigned long addr,
> > unsigned long size,
> >  #define __put_user_inatomic(x, ptr) \
> >       __put_user_nosleep((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
> >
> > +#define __get_user_instr(x, ptr) \
> > +     __get_user_nocheck((x).val, (u32 *)(ptr), sizeof(u32), true)
> > +
> > +#define __get_user_instr_inatomic(x, ptr) \
> > +     __get_user_nosleep((x).val, (u32 *)(ptr), sizeof(u32))
>
>
> should we use ppc_inst_val() ?
The __get_user() macros load a value into the given variable, so we
can not use ppc_inst_val().
>
> -- Bala
>
>
> >  extern long __put_user_bad(void);
> >
> >  /*
> > diff --git a/arch/powerpc/kernel/align.c b/arch/powerpc/kernel/align.c
> > index 66a6d1de7799..65cdfd41e3a1 100644
> > --- a/arch/powerpc/kernel/align.c
> > +++ b/arch/powerpc/kernel/align.c
> > @@ -304,7 +304,7 @@ int fix_alignment(struct pt_regs *regs)
> >        */
> >       CHECK_FULL_REGS(regs);
> >
> > -     if (unlikely(__get_user(instr.val, (unsigned int __user *)regs->nip)))
> > +     if (unlikely(__get_user_instr(instr, (void __user *)regs->nip)))
> >               return -EFAULT;
> >       if ((regs->msr & MSR_LE) != (MSR_KERNEL & MSR_LE)) {
> >               /* We don't handle PPC little-endian any more... */
> > diff --git a/arch/powerpc/kernel/hw_breakpoint.c
> > b/arch/powerpc/kernel/hw_breakpoint.c
> > index 542f65ccf68b..cebab14e2788 100644
> > --- a/arch/powerpc/kernel/hw_breakpoint.c
> > +++ b/arch/powerpc/kernel/hw_breakpoint.c
> > @@ -249,7 +249,7 @@ static bool stepping_handler(struct pt_regs *regs, struct
> > perf_event *bp,
> >       struct instruction_op op;
> >       unsigned long addr = info->address;
> >
> > -     if (__get_user_inatomic(instr.val, (unsigned int *)regs->nip))
> > +     if (__get_user_instr_inatomic(instr, (void __user *)regs->nip))
> >               goto fail;
> >
> >       ret = analyse_instr(&op, regs, instr);
> > diff --git a/arch/powerpc/kernel/vecemu.c b/arch/powerpc/kernel/vecemu.c
> > index bbf536e10902..c82ede46d71b 100644
> > --- a/arch/powerpc/kernel/vecemu.c
> > +++ b/arch/powerpc/kernel/vecemu.c
> > @@ -266,7 +266,7 @@ int emulate_altivec(struct pt_regs *regs)
> >       unsigned int va, vb, vc, vd;
> >       vector128 *vrs;
> >
> > -     if (get_user(instr.val, (unsigned int __user *) regs->nip))
> > +     if (__get_user_instr(instr, (void __user *) regs->nip))
> >               return -EFAULT;
> >
> >       word = ppc_inst_val(instr);
>