diff options
Diffstat (limited to 'arch/powerpc/kernel/signal_64.c')
| -rw-r--r-- | arch/powerpc/kernel/signal_64.c | 93 |
1 files changed, 44 insertions, 49 deletions
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c index 1decf2785530..b3193116e686 100644 --- a/arch/powerpc/kernel/signal_64.c +++ b/arch/powerpc/kernel/signal_64.c @@ -67,40 +67,6 @@ struct rt_sigframe { char abigap[288]; } __attribute__ ((aligned (16))); - -/* - * Atomically swap in the new signal mask, and wait for a signal. - */ -long sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize, int p3, int p4, - int p6, int p7, struct pt_regs *regs) -{ - sigset_t saveset, newset; - - /* XXX: Don't preclude handling different sized sigset_t's. */ - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - - if (copy_from_user(&newset, unewset, sizeof(newset))) - return -EFAULT; - sigdelsetmask(&newset, ~_BLOCKABLE); - - spin_lock_irq(¤t->sighand->siglock); - saveset = current->blocked; - current->blocked = newset; - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - - regs->result = -EINTR; - regs->gpr[3] = EINTR; - regs->ccr |= 0x10000000; - while (1) { - current->state = TASK_INTERRUPTIBLE; - schedule(); - if (do_signal(&saveset, regs)) - return 0; - } -} - long sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, unsigned long r5, unsigned long r6, unsigned long r7, unsigned long r8, struct pt_regs *regs) @@ -152,6 +118,14 @@ static long setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, err |= __put_user(0, &sc->v_regs); #endif /* CONFIG_ALTIVEC */ err |= __put_user(&sc->gp_regs, &sc->regs); + if (!FULL_REGS(regs)) { + /* Zero out the unsaved GPRs to avoid information + leak, and set TIF_SAVE_NVGPRS to ensure that the + registers do actually get saved later. */ + memset(®s->gpr[14], 0, 18 * sizeof(unsigned long)); + set_thread_flag(TIF_SAVE_NVGPRS); + current_thread_info()->nvgprs_frame = &sc->gp_regs; + } err |= __copy_to_user(&sc->gp_regs, regs, GP_REGS_SIZE); err |= __copy_to_user(&sc->fp_regs, ¤t->thread.fpr, FP_REGS_SIZE); err |= __put_user(signr, &sc->signal); @@ -197,10 +171,20 @@ static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig, if (!sig) regs->gpr[13] = save_r13; - err |= __copy_from_user(¤t->thread.fpr, &sc->fp_regs, FP_REGS_SIZE); if (set != NULL) err |= __get_user(set->sig[0], &sc->oldmask); + /* + * Do this before updating the thread state in + * current->thread.fpr/vr. That way, if we get preempted + * and another task grabs the FPU/Altivec, it won't be + * tempted to save the current CPU state into the thread_struct + * and corrupt what we are writing there. + */ + discard_lazy_cpu_state(); + + err |= __copy_from_user(¤t->thread.fpr, &sc->fp_regs, FP_REGS_SIZE); + #ifdef CONFIG_ALTIVEC err |= __get_user(v_regs, &sc->v_regs); err |= __get_user(msr, &sc->gp_regs[PT_MSR]); @@ -219,14 +203,6 @@ static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig, current->thread.vrsave = 0; #endif /* CONFIG_ALTIVEC */ -#ifndef CONFIG_SMP - preempt_disable(); - if (last_task_used_math == current) - last_task_used_math = NULL; - if (last_task_used_altivec == current) - last_task_used_altivec = NULL; - preempt_enable(); -#endif /* Force reload of FP/VEC */ regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1 | MSR_VEC); @@ -340,6 +316,7 @@ int sys_swapcontext(struct ucontext __user *old_ctx, do_exit(SIGSEGV); /* This returns like rt_sigreturn */ + set_thread_flag(TIF_RESTOREALL); return 0; } @@ -372,7 +349,8 @@ int sys_rt_sigreturn(unsigned long r3, unsigned long r4, unsigned long r5, */ do_sigaltstack(&uc->uc_stack, NULL, regs->gpr[1]); - return regs->result; + set_thread_flag(TIF_RESTOREALL); + return 0; badframe: #if DEBUG_SIG @@ -454,9 +432,6 @@ static int setup_rt_frame(int signr, struct k_sigaction *ka, siginfo_t *info, if (err) goto badframe; - if (test_thread_flag(TIF_SINGLESTEP)) - ptrace_notify(SIGTRAP); - return 1; badframe: @@ -502,6 +477,8 @@ static inline void syscall_restart(struct pt_regs *regs, struct k_sigaction *ka) * we only get here if there is a handler, we dont restart. */ regs->result = -EINTR; + regs->gpr[3] = EINTR; + regs->ccr |= 0x10000000; break; case -ERESTARTSYS: /* ERESTARTSYS means to restart the syscall if there is no @@ -509,6 +486,8 @@ static inline void syscall_restart(struct pt_regs *regs, struct k_sigaction *ka) */ if (!(ka->sa.sa_flags & SA_RESTART)) { regs->result = -EINTR; + regs->gpr[3] = EINTR; + regs->ccr |= 0x10000000; break; } /* fallthrough */ @@ -541,11 +520,15 @@ int do_signal(sigset_t *oldset, struct pt_regs *regs) if (test_thread_flag(TIF_32BIT)) return do_signal32(oldset, regs); - if (!oldset) + if (test_thread_flag(TIF_RESTORE_SIGMASK)) + oldset = ¤t->saved_sigmask; + else if (!oldset) oldset = ¤t->blocked; signr = get_signal_to_deliver(&info, &ka, regs, NULL); if (signr > 0) { + int ret; + /* Whee! Actually deliver the signal. */ if (TRAP(regs) == 0x0C00) syscall_restart(regs, &ka); @@ -558,7 +541,14 @@ int do_signal(sigset_t *oldset, struct pt_regs *regs) if (current->thread.dabr) set_dabr(current->thread.dabr); - return handle_signal(signr, &ka, &info, oldset, regs); + ret = handle_signal(signr, &ka, &info, oldset, regs); + + /* If a signal was successfully delivered, the saved sigmask is in + its frame, and we can clear the TIF_RESTORE_SIGMASK flag */ + if (ret && test_thread_flag(TIF_RESTORE_SIGMASK)) + clear_thread_flag(TIF_RESTORE_SIGMASK); + + return ret; } if (TRAP(regs) == 0x0C00) { /* System Call! */ @@ -574,6 +564,11 @@ int do_signal(sigset_t *oldset, struct pt_regs *regs) regs->result = 0; } } + /* No signal to deliver -- put the saved sigmask back */ + if (test_thread_flag(TIF_RESTORE_SIGMASK)) { + clear_thread_flag(TIF_RESTORE_SIGMASK); + sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); + } return 0; } |