1 files changed, 45 insertions, 63 deletions

diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
index 1c83e5124c65..827179c5b32a 100644
--- a/arch/x86/kernel/signal_64.c
+++ b/arch/x86/kernel/signal_64.c
@@ -19,17 +19,28 @@
 #include <linux/stddef.h>
 #include <linux/personality.h>
 #include <linux/compiler.h>
+#include <asm/processor.h>
 #include <asm/ucontext.h>
 #include <asm/uaccess.h>
 #include <asm/i387.h>
 #include <asm/proto.h>
 #include <asm/ia32_unistd.h>
 #include <asm/mce.h>
-
-/* #define DEBUG_SIG 1 */
+#include "sigframe.h"
 
 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
 
+#define __FIX_EFLAGS    (X86_EFLAGS_AC | X86_EFLAGS_OF | \
+                         X86_EFLAGS_DF | X86_EFLAGS_TF | X86_EFLAGS_SF | \
+                         X86_EFLAGS_ZF | X86_EFLAGS_AF | X86_EFLAGS_PF | \
+                         X86_EFLAGS_CF)
+
+#ifdef CONFIG_X86_32
+# define FIX_EFLAGS     (__FIX_EFLAGS | X86_EFLAGS_RF)
+#else
+# define FIX_EFLAGS     __FIX_EFLAGS
+#endif
+
 int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
                sigset_t *set, struct pt_regs * regs); 
 int ia32_setup_frame(int sig, struct k_sigaction *ka,
@@ -46,16 +57,9 @@ sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
 /*
  * Do a signal return; undo the signal stack.
  */
-
-struct rt_sigframe
-{
-        char __user *pretcode;
-        struct ucontext uc;
-        struct siginfo info;
-};
-
 static int
-restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, unsigned long *prax)
+restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
+                   unsigned long *pax)
 {
         unsigned int err = 0;
 
@@ -87,7 +91,7 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, unsigned
         {
                 unsigned int tmpflags;
                 err |= __get_user(tmpflags, &sc->flags);
-                regs->flags = (regs->flags & ~0x40DD5) | (tmpflags & 0x40DD5);
+                regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
                 regs->orig_ax = -1;             /* disable syscall checks */
         }
 
@@ -108,7 +112,7 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, unsigned
                 }
         }
 
-        err |= __get_user(*prax, &sc->ax);
+        err |= __get_user(*pax, &sc->ax);
         return err;
 
 badframe:
@@ -121,13 +125,11 @@ asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
         sigset_t set;
         unsigned long ax;
 
-        frame = (struct rt_sigframe __user *)(regs->sp - 8);
-        if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) {
+        frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long));
+        if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
                 goto badframe;
-        } 
-        if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) { 
+        if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
                 goto badframe;
-        } 
 
         sigdelsetmask(&set, ~_BLOCKABLE);
         spin_lock_irq(&current->sighand->siglock);
@@ -138,10 +140,6 @@ asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
         if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax))
                 goto badframe;
 
-#ifdef DEBUG_SIG
-        printk("%d sigreturn ip:%lx sp:%lx frame:%p ax:%lx\n",current->pid,regs->ip,regs->sp,frame,ax);
-#endif
-
         if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->sp) == -EFAULT)
                 goto badframe;
 
@@ -270,10 +268,6 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
         if (err)
                 goto give_sigsegv;
 
-#ifdef DEBUG_SIG
-        printk("%d old ip %lx old sp %lx old ax %lx\n", current->pid,regs->ip,regs->sp,regs->ax);
-#endif
-
         /* Set up registers for signal handler */
         regs->di = sig;
         /* In case the signal handler was declared without prototypes */ 
@@ -298,10 +292,6 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
         regs->flags &= ~(X86_EFLAGS_TF | X86_EFLAGS_DF);
         if (test_thread_flag(TIF_SINGLESTEP))
                 ptrace_notify(SIGTRAP);
-#ifdef DEBUG_SIG
-        printk("SIG deliver (%s:%d): sp=%p pc=%lx ra=%p\n",
-                current->comm, current->pid, frame, regs->ip, frame->pretcode);
-#endif
 
         return 0;
 
@@ -345,35 +335,29 @@ static long current_syscall_ret(struct pt_regs *regs)
 
 static int
 handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
-                sigset_t *oldset, struct pt_regs *regs)
+              sigset_t *oldset, struct pt_regs *regs)
 {
         int ret;
 
-#ifdef DEBUG_SIG
-        printk("handle_signal pid:%d sig:%lu ip:%lx sp:%lx regs=%p\n",
-                current->pid, sig,
-                regs->ip, regs->sp, regs);
-#endif
-
         /* Are we from a system call? */
         if (current_syscall(regs) >= 0) {
                 /* If so, check system call restarting.. */
                 switch (current_syscall_ret(regs)) {
-                        case -ERESTART_RESTARTBLOCK:
-                        case -ERESTARTNOHAND:
-                                regs->ax = -EINTR;
-                                break;
+                case -ERESTART_RESTARTBLOCK:
+                case -ERESTARTNOHAND:
+                        regs->ax = -EINTR;
+                        break;
 
-                        case -ERESTARTSYS:
-                                if (!(ka->sa.sa_flags & SA_RESTART)) {
-                                        regs->ax = -EINTR;
-                                        break;
-                                }
-                                /* fallthrough */
-                        case -ERESTARTNOINTR:
-                                regs->ax = regs->orig_ax;
-                                regs->ip -= 2;
+                case -ERESTARTSYS:
+                        if (!(ka->sa.sa_flags & SA_RESTART)) {
+                                regs->ax = -EINTR;
                                 break;
+                        }
+                /* fallthrough */
+                case -ERESTARTNOINTR:
+                        regs->ax = regs->orig_ax;
+                        regs->ip -= 2;
+                        break;
                 }
         }
 
@@ -420,10 +404,11 @@ static void do_signal(struct pt_regs *regs)
         sigset_t *oldset;
 
         /*
-         * We want the common case to go fast, which
-         * is why we may in certain cases get here from
-         * kernel mode. Just return without doing anything
+         * We want the common case to go fast, which is why we may in certain
+         * cases get here from kernel mode. Just return without doing anything
          * if so.
+         * X86_32: vm86 regs switched out by assembly code before reaching
+         * here, so testing against kernel CS suffices.
          */
         if (!user_mode(regs))
                 return;
@@ -473,22 +458,19 @@ static void do_signal(struct pt_regs *regs)
                 }
         }
 
-        /* if there's no signal to deliver, we just put the saved sigmask
-           back. */
+        /*
+         * If there's no signal to deliver, we just put the saved sigmask
+         * back.
+         */
         if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
                 clear_thread_flag(TIF_RESTORE_SIGMASK);
                 sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
         }
 }
 
-void
-do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags)
+void do_notify_resume(struct pt_regs *regs, void *unused,
+                      __u32 thread_info_flags)
 {
-#ifdef DEBUG_SIG
-        printk("do_notify_resume flags:%x ip:%lx sp:%lx caller:%p pending:%x\n",
-               thread_info_flags, regs->ip, regs->sp, __builtin_return_address(0),signal_pending(current));
-#endif
-               
         /* Pending single-step? */
         if (thread_info_flags & _TIF_SINGLESTEP) {
                 regs->flags |= X86_EFLAGS_TF;
@@ -502,7 +484,7 @@ do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags)
 #endif /* CONFIG_X86_MCE */
 
         /* deal with pending signal delivery */
-        if (thread_info_flags & (_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK))
+        if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
                 do_signal(regs);
 
         if (thread_info_flags & _TIF_HRTICK_RESCHED)