vserver 2.0 rc7

[linux-2.6.git] / arch / x86_64 / kernel / signal.c

diff --git a/arch/x86_64/kernel/signal.c b/arch/x86_64/kernel/signal.c
index 9cf7038..429c026 100644 (file)
--- a/arch/x86_64/kernel/signal.c
+++ b/arch/x86_64/kernel/signal.c
@@ -28,6 +28,7 @@
 #include <asm/uaccess.h>
 #include <asm/i387.h>
 #include <asm/proto.h>
+#include <asm/ia32_unistd.h>
 
 /* #define DEBUG_SIG 1 */
 
@@ -83,7 +84,7 @@ sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
 
 struct rt_sigframe
 {
-       char *pretcode;
+       char __user *pretcode;
        struct ucontext uc;
        struct siginfo info;
 };
@@ -121,7 +122,7 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, unsigned
                err |= __get_user(buf, &sc->fpstate);
 
                if (buf) {
-                       if (verify_area(VERIFY_READ, buf, sizeof(*buf)))
+                       if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
                                goto badframe;
                        err |= restore_i387(buf);
                } else {
@@ -147,7 +148,7 @@ asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
        unsigned long eax;
 
        frame = (struct rt_sigframe __user *)(regs->rsp - 8);
-       if (verify_area(VERIFY_READ, frame, sizeof(*frame))) { 
+       if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) {
                goto badframe;
        } 
        if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) { 
@@ -160,9 +161,8 @@ asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
        recalc_sigpending();
        spin_unlock_irq(&current->sighand->siglock);
        
-       if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &eax)) {
+       if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &eax))
                goto badframe;
-       } 
 
 #ifdef DEBUG_SIG
        printk("%d sigreturn rip:%lx rsp:%lx frame:%p rax:%lx\n",current->pid,regs.rip,regs.rsp,frame,eax);
@@ -186,7 +186,6 @@ static inline int
 setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, unsigned long mask, struct task_struct *me)
 {
        int err = 0;
-       unsigned long eflags;
 
        err |= __put_user(0, &sc->gs);
        err |= __put_user(0, &sc->fs);
@@ -210,11 +209,7 @@ setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, unsigned lo
        err |= __put_user(me->thread.trap_no, &sc->trapno);
        err |= __put_user(me->thread.error_code, &sc->err);
        err |= __put_user(regs->rip, &sc->rip);
-       eflags = regs->eflags;
-       if (current->ptrace & PT_PTRACED) {
-               eflags &= ~TF_MASK;
-       }
-       err |= __put_user(eflags, &sc->eflags);
+       err |= __put_user(regs->eflags, &sc->eflags);
        err |= __put_user(mask, &sc->oldmask);
        err |= __put_user(me->thread.cr2, &sc->cr2);
 
@@ -253,28 +248,25 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 
        if (used_math()) {
                fp = get_stack(ka, regs, sizeof(struct _fpstate)); 
-               frame = (void __user *)round_down((unsigned long)fp - sizeof(struct rt_sigframe), 16) - 8;
+               frame = (void __user *)round_down(
+                       (unsigned long)fp - sizeof(struct rt_sigframe), 16) - 8;
 
-               if (!access_ok(VERIFY_WRITE, fp, sizeof(struct _fpstate))) { 
-               goto give_sigsegv;
-               }
+               if (!access_ok(VERIFY_WRITE, fp, sizeof(struct _fpstate)))
+                       goto give_sigsegv;
 
                if (save_i387(fp) < 0) 
                        err |= -1; 
-       } else {
+       } else
                frame = get_stack(ka, regs, sizeof(struct rt_sigframe)) - 8;
-       }
 
-       if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) {
+       if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
                goto give_sigsegv;
-       }
 
        if (ka->sa.sa_flags & SA_SIGINFO) { 
                err |= copy_siginfo_to_user(&frame->info, info);
-               if (err) { 
+               if (err)
                        goto give_sigsegv;
        }
-       }
                
        /* Create the ucontext.  */
        err |= __put_user(0, &frame->uc.uc_flags);
@@ -288,9 +280,8 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
        if (sizeof(*set) == 16) { 
                __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
                __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]); 
-       } else {                
-       err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
-       }
+       } else
+               err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
 
        /* Set up to return from userspace.  If provided, use a stub
           already in userspace.  */
@@ -302,9 +293,8 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
                goto give_sigsegv; 
        }
 
-       if (err) { 
+       if (err)
                goto give_sigsegv;
-       } 
 
 #ifdef DEBUG_SIG
        printk("%d old rip %lx old rsp %lx old rax %lx\n", current->pid,regs->rip,regs->rsp,regs->rax);
@@ -329,14 +319,9 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
        regs->rsp = (unsigned long)frame;
 
        set_fs(USER_DS);
-       if (regs->eflags & TF_MASK) {
-               if ((current->ptrace & (PT_PTRACED | PT_DTRACE)) == (PT_PTRACED | PT_DTRACE)) {
-                       ptrace_notify(SIGTRAP);
-               } else {
-                       regs->eflags &= ~TF_MASK;
-               }
-       }
-
+       regs->eflags &= ~TF_MASK;
+       if (test_thread_flag(TIF_SINGLESTEP))
+               ptrace_notify(SIGTRAP);
 #ifdef DEBUG_SIG
        printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
                current->comm, current->pid, frame, regs->rip, frame->pretcode);
@@ -357,7 +342,8 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
                sigset_t *oldset, struct pt_regs *regs)
 {
 #ifdef DEBUG_SIG
-       printk("handle_signal pid:%d sig:%lu rip:%lx rsp:%lx regs=%p\n", current->pid, sig, 
+       printk("handle_signal pid:%d sig:%lu rip:%lx rsp:%lx regs=%p\n",
+               current->pid, sig,
                regs->rip, regs->rsp, regs);
 #endif
 
@@ -375,10 +361,23 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
                                        regs->rax = -EINTR;
                                        break;
                                }
-                       /* fallthrough */
+                               /* fallthrough */
                        case -ERESTARTNOINTR:
                                regs->rax = regs->orig_rax;
                                regs->rip -= 2;
+                               break;
+               }
+       }
+
+       /*
+        * If TF is set due to a debugger (PT_DTRACE), clear the TF
+        * flag so that register information in the sigcontext is
+        * correct.
+        */
+       if (unlikely(regs->eflags & TF_MASK)) {
+               if (likely(current->ptrace & PT_DTRACE)) {
+                       current->ptrace &= ~PT_DTRACE;
+                       regs->eflags &= ~TF_MASK;
                }
        }
 
@@ -418,9 +417,8 @@ int do_signal(struct pt_regs *regs, sigset_t *oldset)
         * kernel mode. Just return without doing anything
         * if so.
         */
-       if ((regs->cs & 3) != 3) {
+       if ((regs->cs & 3) != 3)
                return 1;
-       }       
 
        if (try_to_freeze(0))
                goto no_signal;
@@ -455,7 +453,9 @@ int do_signal(struct pt_regs *regs, sigset_t *oldset)
                        regs->rip -= 2;
                }
                if (regs->rax == (unsigned long)-ERESTART_RESTARTBLOCK) {
-                       regs->rax = __NR_restart_syscall;
+                       regs->rax = test_thread_flag(TIF_IA32) ?
+                                       __NR_ia32_restart_syscall :
+                                       __NR_restart_syscall;
                        regs->rip -= 2;
                }
        }