diff options
Diffstat (limited to 'arch/sparc64/kernel/signal32.c')
-rw-r--r-- | arch/sparc64/kernel/signal32.c | 59 |
1 files changed, 44 insertions, 15 deletions
diff --git a/arch/sparc64/kernel/signal32.c b/arch/sparc64/kernel/signal32.c index 91f8d08..97cdd1b 100644 --- a/arch/sparc64/kernel/signal32.c +++ b/arch/sparc64/kernel/signal32.c @@ -268,6 +268,9 @@ void do_sigreturn32(struct pt_regs *regs) regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC); regs->tstate |= psr_to_tstate_icc(psr); + /* Prevent syscall restart. */ + pt_regs_clear_syscall(regs); + err |= __get_user(fpu_save, &sf->fpu_save); if (fpu_save) err |= restore_fpu_state32(regs, &sf->fpu_state); @@ -351,6 +354,9 @@ asmlinkage void do_rt_sigreturn32(struct pt_regs *regs) regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC); regs->tstate |= psr_to_tstate_icc(psr); + /* Prevent syscall restart. */ + pt_regs_clear_syscall(regs); + err |= __get_user(fpu_save, &sf->fpu_save); if (fpu_save) err |= restore_fpu_state32(regs, &sf->fpu_state); @@ -400,11 +406,27 @@ static void __user *get_sigframe(struct sigaction *sa, struct pt_regs *regs, uns regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL; sp = regs->u_regs[UREG_FP]; + /* + * If we are on the alternate signal stack and would overflow it, don't. + * Return an always-bogus address instead so we will die with SIGSEGV. + */ + if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize))) + return (void __user *) -1L; + /* This is the X/Open sanctioned signal stack switching. */ if (sa->sa_flags & SA_ONSTACK) { - if (!on_sig_stack(sp) && !((current->sas_ss_sp + current->sas_ss_size) & 7)) + if (sas_ss_flags(sp) == 0) sp = current->sas_ss_sp + current->sas_ss_size; } + + /* Always align the stack frame. This handles two cases. First, + * sigaltstack need not be mindful of platform specific stack + * alignment. Second, if we took this signal because the stack + * is not aligned properly, we'd like to take the signal cleanly + * and report that. + */ + sp &= ~7UL; + return (void __user *)(sp - framesize); } @@ -746,48 +768,55 @@ static inline void syscall_restart32(unsigned long orig_i0, struct pt_regs *regs * mistake. */ void do_signal32(sigset_t *oldset, struct pt_regs * regs, - struct signal_deliver_cookie *cookie) + int restart_syscall, unsigned long orig_i0) { struct k_sigaction ka; siginfo_t info; int signr; - signr = get_signal_to_deliver(&info, &ka, regs, cookie); + signr = get_signal_to_deliver(&info, &ka, regs, NULL); + + /* If the debugger messes with the program counter, it clears + * the "in syscall" bit, directing us to not perform a syscall + * restart. + */ + if (restart_syscall && !pt_regs_is_syscall(regs)) + restart_syscall = 0; + if (signr > 0) { - if (cookie->restart_syscall) - syscall_restart32(cookie->orig_i0, regs, &ka.sa); + if (restart_syscall) + syscall_restart32(orig_i0, regs, &ka.sa); handle_signal32(signr, &ka, &info, oldset, regs); - /* a signal was successfully delivered; the saved + /* A signal was successfully delivered; the saved * sigmask will have been stored in the signal frame, * and will be restored by sigreturn, so we can simply - * clear the TIF_RESTORE_SIGMASK flag. + * clear the TS_RESTORE_SIGMASK flag. */ - if (test_thread_flag(TIF_RESTORE_SIGMASK)) - clear_thread_flag(TIF_RESTORE_SIGMASK); + current_thread_info()->status &= ~TS_RESTORE_SIGMASK; return; } - if (cookie->restart_syscall && + if (restart_syscall && (regs->u_regs[UREG_I0] == ERESTARTNOHAND || regs->u_regs[UREG_I0] == ERESTARTSYS || regs->u_regs[UREG_I0] == ERESTARTNOINTR)) { /* replay the system call when we are done */ - regs->u_regs[UREG_I0] = cookie->orig_i0; + regs->u_regs[UREG_I0] = orig_i0; regs->tpc -= 4; regs->tnpc -= 4; } - if (cookie->restart_syscall && + if (restart_syscall && regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) { regs->u_regs[UREG_G1] = __NR_restart_syscall; regs->tpc -= 4; regs->tnpc -= 4; } - /* if there's no signal to deliver, we just put the saved sigmask + /* 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); + if (current_thread_info()->status & TS_RESTORE_SIGMASK) { + current_thread_info()->status &= ~TS_RESTORE_SIGMASK; sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); } } |