6 files changed, 25 insertions, 25 deletions

diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c
index a866411a2fcc..a1daf4a65009 100644
--- a/arch/x86/ia32/ia32_signal.c
+++ b/arch/x86/ia32/ia32_signal.c
@@ -467,10 +467,7 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
                 else
                         put_user_ex(0, &frame->uc.uc_flags);
                 put_user_ex(0, &frame->uc.uc_link);
-                put_user_ex(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
-                put_user_ex(sas_ss_flags(regs->sp),
-                            &frame->uc.uc_stack.ss_flags);
-                put_user_ex(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+                err |= __compat_save_altstack(&frame->uc.uc_stack, regs->sp);
 
                 if (ka->sa.sa_flags & SA_RESTORER)
                         restorer = ka->sa.sa_restorer;
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index b17ed37c61a2..a6c8a347b8c6 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -363,10 +363,7 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
                 else
                         put_user_ex(0, &frame->uc.uc_flags);
                 put_user_ex(0, &frame->uc.uc_link);
-                put_user_ex(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
-                put_user_ex(sas_ss_flags(regs->sp),
-                            &frame->uc.uc_stack.ss_flags);
-                put_user_ex(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+                err |= __save_altstack(&frame->uc.uc_stack, regs->sp);
 
                 /* Set up to return from userspace.  */
                 restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn);
@@ -413,7 +410,6 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
         struct rt_sigframe __user *frame;
         void __user *fp = NULL;
         int err = 0;
-        struct task_struct *me = current;
 
         frame = get_sigframe(ka, regs, sizeof(struct rt_sigframe), &fp);
 
@@ -432,10 +428,7 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
                 else
                         put_user_ex(0, &frame->uc.uc_flags);
                 put_user_ex(0, &frame->uc.uc_link);
-                put_user_ex(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
-                put_user_ex(sas_ss_flags(regs->sp),
-                            &frame->uc.uc_stack.ss_flags);
-                put_user_ex(me->sas_ss_size, &frame->uc.uc_stack.ss_size);
+                err |= __save_altstack(&frame->uc.uc_stack, regs->sp);
 
                 /* Set up to return from userspace.  If provided, use a stub
                    already in userspace.  */
@@ -502,10 +495,7 @@ static int x32_setup_rt_frame(int sig, struct k_sigaction *ka,
                 else
                         put_user_ex(0, &frame->uc.uc_flags);
                 put_user_ex(0, &frame->uc.uc_link);
-                put_user_ex(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
-                put_user_ex(sas_ss_flags(regs->sp),
-                            &frame->uc.uc_stack.ss_flags);
-                put_user_ex(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+                err |= __compat_save_altstack(&frame->uc.uc_stack, regs->sp);
                 put_user_ex(0, &frame->uc.uc__pad0);
 
                 if (ka->sa.sa_flags & SA_RESTORER) {
@@ -651,7 +641,7 @@ long sys_rt_sigreturn(struct pt_regs *regs)
         if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax))
                 goto badframe;
 
-        if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->sp) == -EFAULT)
+        if (restore_altstack(&frame->uc.uc_stack))
                 goto badframe;
 
         return ax;
diff --git a/arch/x86/um/signal.c b/arch/x86/um/signal.c
index bdaa08cfbcf4..71cef48ea5cd 100644
--- a/arch/x86/um/signal.c
+++ b/arch/x86/um/signal.c
@@ -342,9 +342,7 @@ static int copy_ucontext_to_user(struct ucontext __user *uc,
 {
         int err = 0;
 
-        err |= put_user(current->sas_ss_sp, &uc->uc_stack.ss_sp);
-        err |= put_user(sas_ss_flags(sp), &uc->uc_stack.ss_flags);
-        err |= put_user(current->sas_ss_size, &uc->uc_stack.ss_size);
+        err |= __save_altstack(&uc->uc_stack, sp);
         err |= copy_sc_to_user(&uc->uc_mcontext, fp, &current->thread.regs, 0);
         err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
         return err;
@@ -529,10 +527,7 @@ int setup_signal_stack_si(unsigned long stack_top, int sig,
         /* Create the ucontext.  */
         err |= __put_user(0, &frame->uc.uc_flags);
         err |= __put_user(0, &frame->uc.uc_link);
-        err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
-        err |= __put_user(sas_ss_flags(PT_REGS_SP(regs)),
-                          &frame->uc.uc_stack.ss_flags);
-        err |= __put_user(me->sas_ss_size, &frame->uc.uc_stack.ss_size);
+        err |= __save_altstack(&frame->uc.uc_stack, PT_REGS_SP(regs));
         err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs,
                                set->sig[0]);
         err |= __put_user(&frame->fpstate, &frame->uc.uc_mcontext.fpstate);
diff --git a/include/linux/compat.h b/include/linux/compat.h
index cb5637e2ee2c..334813307ec1 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -647,6 +647,7 @@ asmlinkage long compat_sys_sigaltstack(const compat_stack_t __user *uss_ptr,
                                        compat_stack_t __user *uoss_ptr);
 
 int compat_restore_altstack(const compat_stack_t __user *uss);
+int __compat_save_altstack(compat_stack_t __user *, unsigned long);
 #endif
 
 #else
diff --git a/include/linux/signal.h b/include/linux/signal.h
index 5969522136fe..0a89ffc48466 100644
--- a/include/linux/signal.h
+++ b/include/linux/signal.h
@@ -386,5 +386,6 @@ int unhandled_signal(struct task_struct *tsk, int sig);
 void signals_init(void);
 
 int restore_altstack(const stack_t __user *);
+int __save_altstack(stack_t __user *, unsigned long);
 
 #endif /* _LINUX_SIGNAL_H */
diff --git a/kernel/signal.c b/kernel/signal.c
index aee85bd76b8a..f072513302c3 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -3117,6 +3117,14 @@ int restore_altstack(const stack_t __user *uss)
         return err == -EFAULT ? err : 0;
 }
 
+int __save_altstack(stack_t __user *uss, unsigned long sp)
+{
+        struct task_struct *t = current;
+        return  __put_user((void __user *)t->sas_ss_sp, &uss->ss_sp) |
+                __put_user(sas_ss_flags(sp), &uss->ss_flags) |
+                __put_user(t->sas_ss_size, &uss->ss_size);
+}
+
 #ifdef CONFIG_COMPAT
 #ifdef CONFIG_GENERIC_SIGALTSTACK
 asmlinkage long compat_sys_sigaltstack(const compat_stack_t __user *uss_ptr,
@@ -3158,6 +3166,14 @@ int compat_restore_altstack(const compat_stack_t __user *uss)
         /* squash all but -EFAULT for now */
         return err == -EFAULT ? err : 0;
 }
+
+int __compat_save_altstack(compat_stack_t __user *uss, unsigned long sp)
+{
+        struct task_struct *t = current;
+        return  __put_user(ptr_to_compat((void __user *)t->sas_ss_sp), &uss->ss_sp) |
+                __put_user(sas_ss_flags(sp), &uss->ss_flags) |
+                __put_user(t->sas_ss_size, &uss->ss_size);
+}
 #endif
 #endif