1 files changed, 21 insertions, 88 deletions

diff --git a/arch/microblaze/kernel/signal.c b/arch/microblaze/kernel/signal.c
index 40d36931e363..4c0e6521b114 100644
--- a/arch/microblaze/kernel/signal.c
+++ b/arch/microblaze/kernel/signal.c
@@ -152,8 +152,8 @@ struct rt_sigframe {
         unsigned long tramp[2]; /* signal trampoline */
 };
 
-static int
-restore_sigcontext(struct pt_regs *regs, struct sigcontext *sc, int *rval_p)
+static int restore_sigcontext(struct pt_regs *regs,
+                                struct sigcontext __user *sc, int *rval_p)
 {
         unsigned int err = 0;
 
@@ -211,11 +211,10 @@ badframe:
 
 asmlinkage int sys_rt_sigreturn(struct pt_regs *regs)
 {
-        struct rt_sigframe *frame =
-                        (struct rt_sigframe *)(regs->r1 + STATE_SAVE_ARG_SPACE);
+        struct rt_sigframe __user *frame =
+                (struct rt_sigframe __user *)(regs->r1 + STATE_SAVE_ARG_SPACE);
 
         sigset_t set;
-        stack_t st;
         int rval;
 
         if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
@@ -233,11 +232,10 @@ asmlinkage int sys_rt_sigreturn(struct pt_regs *regs)
         if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &rval))
                 goto badframe;
 
-        if (__copy_from_user((void *)&st, &frame->uc.uc_stack, sizeof(st)))
-                goto badframe;
         /* It is more difficult to avoid calling this function than to
          call it and ignore errors. */
-        do_sigaltstack(&st, NULL, regs->r1);
+        if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->r1))
+                goto badframe;
 
         return rval;
 
@@ -251,7 +249,7 @@ badframe:
  */
 
 static int
-setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
+setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
                 unsigned long mask)
 {
         int err = 0;
@@ -278,7 +276,7 @@ setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
 /*
  * Determine which stack to use..
  */
-static inline void *
+static inline void __user *
 get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
 {
         /* Default to using normal stack */
@@ -287,87 +285,13 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
         if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && !on_sig_stack(sp))
                 sp = current->sas_ss_sp + current->sas_ss_size;
 
-        return (void *)((sp - frame_size) & -8UL);
-}
-
-static void setup_frame(int sig, struct k_sigaction *ka,
-                        sigset_t *set, struct pt_regs *regs)
-{
-        struct sigframe *frame;
-        int err = 0;
-        int signal;
-
-        frame = get_sigframe(ka, regs, sizeof(*frame));
-
-        if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
-                goto give_sigsegv;
-
-        signal = current_thread_info()->exec_domain
-                && current_thread_info()->exec_domain->signal_invmap
-                && sig < 32
-                ? current_thread_info()->exec_domain->signal_invmap[sig]
-                : sig;
-
-        err |= setup_sigcontext(&frame->sc, regs, set->sig[0]);
-
-        if (_NSIG_WORDS > 1) {
-                err |= __copy_to_user(frame->extramask, &set->sig[1],
-                                        sizeof(frame->extramask));
-        }
-
-        /* Set up to return from userspace. If provided, use a stub
-         already in userspace. */
-        /* minus 8 is offset to cater for "rtsd r15,8" offset */
-        if (ka->sa.sa_flags & SA_RESTORER) {
-                regs->r15 = ((unsigned long)ka->sa.sa_restorer)-8;
-        } else {
-                /* Note, these encodings are _big endian_! */
-
-                /* addi r12, r0, __NR_sigreturn */
-                err |= __put_user(0x31800000 | __NR_sigreturn ,
-                                frame->tramp + 0);
-                /* brki r14, 0x8 */
-                err |= __put_user(0xb9cc0008, frame->tramp + 1);
-
-                /* Return from sighandler will jump to the tramp.
-                 Negative 8 offset because return is rtsd r15, 8 */
-                regs->r15 = ((unsigned long)frame->tramp)-8;
-
-                __invalidate_cache_sigtramp((unsigned long)frame->tramp);
-        }
-
-        if (err)
-                goto give_sigsegv;
-
-        /* Set up registers for signal handler */
-        regs->r1 = (unsigned long) frame - STATE_SAVE_ARG_SPACE;
-
-        /* Signal handler args: */
-        regs->r5 = signal; /* Arg 0: signum */
-        regs->r6 = (unsigned long) &frame->sc; /* arg 1: sigcontext */
-
-        /* Offset of 4 to handle microblaze rtid r14, 0 */
-        regs->pc = (unsigned long)ka->sa.sa_handler;
-
-        set_fs(USER_DS);
-
-#ifdef DEBUG_SIG
-        printk(KERN_INFO "SIG deliver (%s:%d): sp=%p pc=%08lx\n",
-                current->comm, current->pid, frame, regs->pc);
-#endif
-
-        return;
-
-give_sigsegv:
-        if (sig == SIGSEGV)
-                ka->sa.sa_handler = SIG_DFL;
-        force_sig(SIGSEGV, current);
+        return (void __user *)((sp - frame_size) & -8UL);
 }
 
 static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
                         sigset_t *set, struct pt_regs *regs)
 {
-        struct rt_sigframe *frame;
+        struct rt_sigframe __user *frame;
         int err = 0;
         int signal;
 
@@ -382,7 +306,8 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
                 ? current_thread_info()->exec_domain->signal_invmap[sig]
                 : sig;
 
-        err |= copy_siginfo_to_user(&frame->info, info);
+        if (info)
+                err |= copy_siginfo_to_user(&frame->info, info);
 
         /* Create the ucontext. */
         err |= __put_user(0, &frame->uc.uc_flags);
@@ -463,7 +388,15 @@ handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
         case -ERESTARTNOINTR:
 do_restart:
                 /* offset of 4 bytes to re-execute trap (brki) instruction */
+#ifndef CONFIG_MMU
                 regs->pc -= 4;
+#else
+                /* offset of 8 bytes required = 4 for rtbd
+                   offset, plus 4 for size of
+                        "brki r14,8"
+                   instruction. */
+                regs->pc -= 8;
+#endif
                 break;
         }
 }
@@ -480,7 +413,7 @@ handle_signal(unsigned long sig, struct k_sigaction *ka,
         if (ka->sa.sa_flags & SA_SIGINFO)
                 setup_rt_frame(sig, ka, info, oldset, regs);
         else
-                setup_frame(sig, ka, oldset, regs);
+                setup_rt_frame(sig, ka, NULL, oldset, regs);
 
         if (ka->sa.sa_flags & SA_ONESHOT)
                 ka->sa.sa_handler = SIG_DFL;