Re: [PATCH] ilp32: fix {GET,SET}SIGMASK request for ptrace

[zhouchengming]

On 2016/6/27 13:39, Yury Norov wrote:
> Hi Zhou,
>
> Thank you for the patch. The idea is ok, but patch format got broken
> for some reason. Could you re-send it?
>
> Yury.

Sorry for the broken patch, maybe my mail guest has some problems. So
I send the patch as an attachment.

Thanks!

> On Mon, Jun 27, 2016 at 12:49:05PM +0800, zhouchengming wrote:
> > atus: RO
> > Content-Length: 4732
> > Lines: 181
> >
> > The function compat_ptrace_request(used by ilp32) don't handle
> > {GET,SET}SIGMASK request, so it will be handled by ptrace_request.
> > But it's wrong because the compat_sigset_t of ilp32 differs from
> > the sigset_t of aarch64. The patch fixes it.
> >
> > Signed-off-by: Zhou Chengming<zhouchengming1@xxxxxxxxxx>
> > ---
> >   arch/arm64/include/asm/signal_ilp32.h |   22 ++++++++++++
> >   arch/arm64/kernel/ptrace.c            |   62
> > +++++++++++++++++++++++++++++++++
>
> Here -  unneeded line break
>
> >   arch/arm64/kernel/signal_ilp32.c      |   23 +------------
> >   3 files changed, 85 insertions(+), 22 deletions(-)
> >
> > diff --git a/arch/arm64/include/asm/signal_ilp32.h
> > b/arch/arm64/include/asm/signal_ilp32.h
>
> and here
>
> > index 30eff23..ed52607 100644
> > --- a/arch/arm64/include/asm/signal_ilp32.h
> > +++ b/arch/arm64/include/asm/signal_ilp32.h
> > @@ -21,6 +21,28 @@
> >   int ilp32_setup_rt_frame(int usig, struct ksignal *ksig, sigset_t *set,
> >   			  struct pt_regs *regs);
> >
> > +static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
> > +{
> > +	compat_sigset_t cset;
> > +
> > +	cset.sig[0] = set->sig[0]&  0xffffffffull;
> > +	cset.sig[1] = set->sig[0]>>  32;
> > +
> > +	return copy_to_user(uset,&cset, sizeof(*uset));
> > +}
> > +
> > +static inline int get_sigset_t(sigset_t *set,
> > +			       const compat_sigset_t __user *uset)
> > +{
> > +	compat_sigset_t s32;
> > +
> > +	if (copy_from_user(&s32, uset, sizeof(*uset)))
> > +		return -EFAULT;
> > +
> > +	set->sig[0] = s32.sig[0] | (((long)s32.sig[1])<<  32);
> > +	return 0;
> > +}
> > +
> >   #else
> >
> >   static inline int ilp32_setup_rt_frame(int usig, struct ksignal *ksig,
> > sigset_t *set,
>
> and here
>
> > diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
> > index a861105..8d4cad1 100644
> > --- a/arch/arm64/kernel/ptrace.c
> > +++ b/arch/arm64/kernel/ptrace.c
> > @@ -44,6 +44,7 @@
> >   #include<asm/syscall.h>
> >   #include<asm/traps.h>
> >   #include<asm/system_misc.h>
> > +#include<asm/signal_ilp32.h>
> >
> >   #define CREATE_TRACE_POINTS
> >   #include<trace/events/syscalls.h>
> > @@ -1231,12 +1232,73 @@ COMPAT_SYSCALL_DEFINE4(aarch32_ptrace,
> > compat_long_t, request, compat_long_t, pi
>
> and later on the patch
>
> >   #endif /* CONFIG_AARCH32_EL0 */
> >
> > +#ifdef CONFIG_ARM64_ILP32
> > +
> > +static int compat_ilp32_ptrace(struct task_struct *child, compat_long_t
> > request,
> > +			compat_ulong_t addr, compat_ulong_t data)
> > +{
> > +	compat_ulong_t __user *datap = compat_ptr(data);
> > +	int ret;
> > +
> > +	switch (request) {
> > +	case PTRACE_GETSIGMASK:
> > +		if (addr != sizeof(compat_sigset_t)) {
> > +			ret = -EINVAL;
> > +			break;
> > +		}
> > +
> > +		if (put_sigset_t((compat_sigset_t __user *)datap,&child->blocked))
> > +			ret = -EFAULT;
> > +		else
> > +			ret = 0;
> > +		break;
> > +
> > +	case PTRACE_SETSIGMASK: {
> > +		sigset_t new_set;
> > +		if (addr != sizeof(compat_sigset_t)) {
> > +			ret = -EINVAL;
> > +			break;
> > +		}
> > +
> > +		if (get_sigset_t(&new_set, (compat_sigset_t __user *)datap)) {
> > +			ret = -EFAULT;
> > +			break;
> > +		}
> > +
> > +		sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
> > +
> > +		/*
> > +		 * Every thread does recalc_sigpending() after resume, so
> > +		 * retarget_shared_pending() and recalc_sigpending() are not
> > +		 * called here.
> > +		 */
> > +		spin_lock_irq(&child->sighand->siglock);
> > +		child->blocked = new_set;
> > +		spin_unlock_irq(&child->sighand->siglock);
> > +
> > +		ret = 0;
> > +		break;
> > +	}
> > +
> > +	default:
> > +		ret = compat_ptrace_request(child, request, addr, data);
> > +	}
> > +
> > +	return ret;
> > +}
> > +
> > +#endif /* CONFIG_ARM64_ILP32 */
> > +
> >   #ifdef CONFIG_COMPAT
> >
> >   long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
> >   			compat_ulong_t caddr, compat_ulong_t cdata)
> >   {
> > +#ifdef CONFIG_ARM64_ILP32
> > +	return compat_ilp32_ptrace(child, request, caddr, cdata);
> > +#else
> >   	return compat_ptrace_request(child, request, caddr, cdata);
> > +#endif
> >   }
> >
> >   #endif /* CONFIG_COMPAT */
> > diff --git a/arch/arm64/kernel/signal_ilp32.c
> > b/arch/arm64/kernel/signal_ilp32.c
> > index 8ca64b9..3ef2749 100644
> > --- a/arch/arm64/kernel/signal_ilp32.c
> > +++ b/arch/arm64/kernel/signal_ilp32.c
> > @@ -28,6 +28,7 @@
> >   #include<asm/fpsimd.h>
> >   #include<asm/signal32_common.h>
> >   #include<asm/signal_common.h>
> > +#include<asm/signal_ilp32.h>
> >   #include<asm/uaccess.h>
> >   #include<asm/unistd.h>
> >   #include<asm/ucontext.h>
> > @@ -58,28 +59,6 @@ struct ilp32_rt_sigframe {
> >   	struct ilp32_sigframe sig;
> >   };
> >
> > -static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
> > -{
> > -	compat_sigset_t cset;
> > -
> > -	cset.sig[0] = set->sig[0]&  0xffffffffull;
> > -	cset.sig[1] = set->sig[0]>>  32;
> > -
> > -	return copy_to_user(uset,&cset, sizeof(*uset));
> > -}
> > -
> > -static inline int get_sigset_t(sigset_t *set,
> > -                               const compat_sigset_t __user *uset)
> > -{
> > -	compat_sigset_t s32;
> > -
> > -	if (copy_from_user(&s32, uset, sizeof(*uset)))
> > -		return -EFAULT;
> > -
> > -	set->sig[0] = s32.sig[0] | (((long)s32.sig[1])<<  32);
> > -	return 0;
> > -}
> > -
> >   static int restore_ilp32_sigframe(struct pt_regs *regs,
> >                               struct
>
> .