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

Yury Norov
2016-06-27T05:39:16Z

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.

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@huawei.com>
> ---
> 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